Itsa me, quake3io!

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+The Independent JPEG Group's JPEG software
+==========================================
+
+README for release 6b of 27-Mar-1998
+====================================
+
+This distribution contains the sixth public release of the Independent JPEG
+Group's free JPEG software.  You are welcome to redistribute this software and
+to use it for any purpose, subject to the conditions under LEGAL ISSUES, below.
+
+Serious users of this software (particularly those incorporating it into
+larger programs) should contact IJG at jpeg-info@uunet.uu.net to be added to
+our electronic mailing list.  Mailing list members are notified of updates
+and have a chance to participate in technical discussions, etc.
+
+This software is the work of Tom Lane, Philip Gladstone, Jim Boucher,
+Lee Crocker, Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi,
+Guido Vollbeding, Ge' Weijers, and other members of the Independent JPEG
+Group.
+
+IJG is not affiliated with the official ISO JPEG standards committee.
+
+
+DOCUMENTATION ROADMAP
+=====================
+
+This file contains the following sections:
+
+OVERVIEW            General description of JPEG and the IJG software.
+LEGAL ISSUES        Copyright, lack of warranty, terms of distribution.
+REFERENCES          Where to learn more about JPEG.
+ARCHIVE LOCATIONS   Where to find newer versions of this software.
+RELATED SOFTWARE    Other stuff you should get.
+FILE FORMAT WARS    Software *not* to get.
+TO DO               Plans for future IJG releases.
+
+Other documentation files in the distribution are:
+
+User documentation:
+  install.doc       How to configure and install the IJG software.
+  usage.doc         Usage instructions for cjpeg, djpeg, jpegtran,
+                    rdjpgcom, and wrjpgcom.
+  *.1               Unix-style man pages for programs (same info as usage.doc).
+  wizard.doc        Advanced usage instructions for JPEG wizards only.
+  change.log        Version-to-version change highlights.
+Programmer and internal documentation:
+  libjpeg.doc       How to use the JPEG library in your own programs.
+  example.c         Sample code for calling the JPEG library.
+  structure.doc     Overview of the JPEG library's internal structure.
+  filelist.doc      Road map of IJG files.
+  coderules.doc     Coding style rules --- please read if you contribute code.
+
+Please read at least the files install.doc and usage.doc.  Useful information
+can also be found in the JPEG FAQ (Frequently Asked Questions) article.  See
+ARCHIVE LOCATIONS below to find out where to obtain the FAQ article.
+
+If you want to understand how the JPEG code works, we suggest reading one or
+more of the REFERENCES, then looking at the documentation files (in roughly
+the order listed) before diving into the code.
+
+
+OVERVIEW
+========
+
+This package contains C software to implement JPEG image compression and
+decompression.  JPEG (pronounced "jay-peg") is a standardized compression
+method for full-color and gray-scale images.  JPEG is intended for compressing
+"real-world" scenes; line drawings, cartoons and other non-realistic images
+are not its strong suit.  JPEG is lossy, meaning that the output image is not
+exactly identical to the input image.  Hence you must not use JPEG if you
+have to have identical output bits.  However, on typical photographic images,
+very good compression levels can be obtained with no visible change, and
+remarkably high compression levels are possible if you can tolerate a
+low-quality image.  For more details, see the references, or just experiment
+with various compression settings.
+
+This software implements JPEG baseline, extended-sequential, and progressive
+compression processes.  Provision is made for supporting all variants of these
+processes, although some uncommon parameter settings aren't implemented yet.
+For legal reasons, we are not distributing code for the arithmetic-coding
+variants of JPEG; see LEGAL ISSUES.  We have made no provision for supporting
+the hierarchical or lossless processes defined in the standard.
+
+We provide a set of library routines for reading and writing JPEG image files,
+plus two sample applications "cjpeg" and "djpeg", which use the library to
+perform conversion between JPEG and some other popular image file formats.
+The library is intended to be reused in other applications.
+
+In order to support file conversion and viewing software, we have included
+considerable functionality beyond the bare JPEG coding/decoding capability;
+for example, the color quantization modules are not strictly part of JPEG
+decoding, but they are essential for output to colormapped file formats or
+colormapped displays.  These extra functions can be compiled out of the
+library if not required for a particular application.  We have also included
+"jpegtran", a utility for lossless transcoding between different JPEG
+processes, and "rdjpgcom" and "wrjpgcom", two simple applications for
+inserting and extracting textual comments in JFIF files.
+
+The emphasis in designing this software has been on achieving portability and
+flexibility, while also making it fast enough to be useful.  In particular,
+the software is not intended to be read as a tutorial on JPEG.  (See the
+REFERENCES section for introductory material.)  Rather, it is intended to
+be reliable, portable, industrial-strength code.  We do not claim to have
+achieved that goal in every aspect of the software, but we strive for it.
+
+We welcome the use of this software as a component of commercial products.
+No royalty is required, but we do ask for an acknowledgement in product
+documentation, as described under LEGAL ISSUES.
+
+
+LEGAL ISSUES
+============
+
+In plain English:
+
+1. We don't promise that this software works.  (But if you find any bugs,
+   please let us know!)
+2. You can use this software for whatever you want.  You don't have to pay us.
+3. You may not pretend that you wrote this software.  If you use it in a
+   program, you must acknowledge somewhere in your documentation that
+   you've used the IJG code.
+
+In legalese:
+
+The authors make NO WARRANTY or representation, either express or implied,
+with respect to this software, its quality, accuracy, merchantability, or
+fitness for a particular purpose.  This software is provided "AS IS", and you,
+its user, assume the entire risk as to its quality and accuracy.
+
+This software is copyright (C) 1991-1998, Thomas G. Lane.
+All Rights Reserved except as specified below.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+software (or portions thereof) for any purpose, without fee, subject to these
+conditions:
+(1) If any part of the source code for this software is distributed, then this
+README file must be included, with this copyright and no-warranty notice
+unaltered; and any additions, deletions, or changes to the original files
+must be clearly indicated in accompanying documentation.
+(2) If only executable code is distributed, then the accompanying
+documentation must state that "this software is based in part on the work of
+the Independent JPEG Group".
+(3) Permission for use of this software is granted only if the user accepts
+full responsibility for any undesirable consequences; the authors accept
+NO LIABILITY for damages of any kind.
+
+These conditions apply to any software derived from or based on the IJG code,
+not just to the unmodified library.  If you use our work, you ought to
+acknowledge us.
+
+Permission is NOT granted for the use of any IJG author's name or company name
+in advertising or publicity relating to this software or products derived from
+it.  This software may be referred to only as "the Independent JPEG Group's
+software".
+
+We specifically permit and encourage the use of this software as the basis of
+commercial products, provided that all warranty or liability claims are
+assumed by the product vendor.
+
+
+ansi2knr.c is included in this distribution by permission of L. Peter Deutsch,
+sole proprietor of its copyright holder, Aladdin Enterprises of Menlo Park, CA.
+ansi2knr.c is NOT covered by the above copyright and conditions, but instead
+by the usual distribution terms of the Free Software Foundation; principally,
+that you must include source code if you redistribute it.  (See the file
+ansi2knr.c for full details.)  However, since ansi2knr.c is not needed as part
+of any program generated from the IJG code, this does not limit you more than
+the foregoing paragraphs do.
+
+The Unix configuration script "configure" was produced with GNU Autoconf.
+It is copyright by the Free Software Foundation but is freely distributable.
+The same holds for its supporting scripts (config.guess, config.sub,
+ltconfig, ltmain.sh).  Another support script, install-sh, is copyright
+by M.I.T. but is also freely distributable.
+
+It appears that the arithmetic coding option of the JPEG spec is covered by
+patents owned by IBM, AT&T, and Mitsubishi.  Hence arithmetic coding cannot
+legally be used without obtaining one or more licenses.  For this reason,
+support for arithmetic coding has been removed from the free JPEG software.
+(Since arithmetic coding provides only a marginal gain over the unpatented
+Huffman mode, it is unlikely that very many implementations will support it.)
+So far as we are aware, there are no patent restrictions on the remaining
+code.
+
+The IJG distribution formerly included code to read and write GIF files.
+To avoid entanglement with the Unisys LZW patent, GIF reading support has
+been removed altogether, and the GIF writer has been simplified to produce
+"uncompressed GIFs".  This technique does not use the LZW algorithm; the
+resulting GIF files are larger than usual, but are readable by all standard
+GIF decoders.
+
+We are required to state that
+    "The Graphics Interchange Format(c) is the Copyright property of
+    CompuServe Incorporated.  GIF(sm) is a Service Mark property of
+    CompuServe Incorporated."
+
+
+REFERENCES
+==========
+
+We highly recommend reading one or more of these references before trying to
+understand the innards of the JPEG software.
+
+The best short technical introduction to the JPEG compression algorithm is
+	Wallace, Gregory K.  "The JPEG Still Picture Compression Standard",
+	Communications of the ACM, April 1991 (vol. 34 no. 4), pp. 30-44.
+(Adjacent articles in that issue discuss MPEG motion picture compression,
+applications of JPEG, and related topics.)  If you don't have the CACM issue
+handy, a PostScript file containing a revised version of Wallace's article is
+available at ftp://ftp.uu.net/graphics/jpeg/wallace.ps.gz.  The file (actually
+a preprint for an article that appeared in IEEE Trans. Consumer Electronics)
+omits the sample images that appeared in CACM, but it includes corrections
+and some added material.  Note: the Wallace article is copyright ACM and IEEE,
+and it may not be used for commercial purposes.
+
+A somewhat less technical, more leisurely introduction to JPEG can be found in
+"The Data Compression Book" by Mark Nelson and Jean-loup Gailly, published by
+M&T Books (New York), 2nd ed. 1996, ISBN 1-55851-434-1.  This book provides
+good explanations and example C code for a multitude of compression methods
+including JPEG.  It is an excellent source if you are comfortable reading C
+code but don't know much about data compression in general.  The book's JPEG
+sample code is far from industrial-strength, but when you are ready to look
+at a full implementation, you've got one here...
+
+The best full description of JPEG is the textbook "JPEG Still Image Data
+Compression Standard" by William B. Pennebaker and Joan L. Mitchell, published
+by Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1.  Price US$59.95, 638 pp.
+The book includes the complete text of the ISO JPEG standards (DIS 10918-1
+and draft DIS 10918-2).  This is by far the most complete exposition of JPEG
+in existence, and we highly recommend it.
+
+The JPEG standard itself is not available electronically; you must order a
+paper copy through ISO or ITU.  (Unless you feel a need to own a certified
+official copy, we recommend buying the Pennebaker and Mitchell book instead;
+it's much cheaper and includes a great deal of useful explanatory material.)
+In the USA, copies of the standard may be ordered from ANSI Sales at (212)
+642-4900, or from Global Engineering Documents at (800) 854-7179.  (ANSI
+doesn't take credit card orders, but Global does.)  It's not cheap: as of
+1992, ANSI was charging $95 for Part 1 and $47 for Part 2, plus 7%
+shipping/handling.  The standard is divided into two parts, Part 1 being the
+actual specification, while Part 2 covers compliance testing methods.  Part 1
+is titled "Digital Compression and Coding of Continuous-tone Still Images,
+Part 1: Requirements and guidelines" and has document numbers ISO/IEC IS
+10918-1, ITU-T T.81.  Part 2 is titled "Digital Compression and Coding of
+Continuous-tone Still Images, Part 2: Compliance testing" and has document
+numbers ISO/IEC IS 10918-2, ITU-T T.83.
+
+Some extensions to the original JPEG standard are defined in JPEG Part 3,
+a newer ISO standard numbered ISO/IEC IS 10918-3 and ITU-T T.84.  IJG
+currently does not support any Part 3 extensions.
+
+The JPEG standard does not specify all details of an interchangeable file
+format.  For the omitted details we follow the "JFIF" conventions, revision
+1.02.  A copy of the JFIF spec is available from:
+	Literature Department
+	C-Cube Microsystems, Inc.
+	1778 McCarthy Blvd.
+	Milpitas, CA 95035
+	phone (408) 944-6300,  fax (408) 944-6314
+A PostScript version of this document is available by FTP at
+ftp://ftp.uu.net/graphics/jpeg/jfif.ps.gz.  There is also a plain text
+version at ftp://ftp.uu.net/graphics/jpeg/jfif.txt.gz, but it is missing
+the figures.
+
+The TIFF 6.0 file format specification can be obtained by FTP from
+ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz.  The JPEG incorporation scheme
+found in the TIFF 6.0 spec of 3-June-92 has a number of serious problems.
+IJG does not recommend use of the TIFF 6.0 design (TIFF Compression tag 6).
+Instead, we recommend the JPEG design proposed by TIFF Technical Note #2
+(Compression tag 7).  Copies of this Note can be obtained from ftp.sgi.com or
+from ftp://ftp.uu.net/graphics/jpeg/.  It is expected that the next revision
+of the TIFF spec will replace the 6.0 JPEG design with the Note's design.
+Although IJG's own code does not support TIFF/JPEG, the free libtiff library
+uses our library to implement TIFF/JPEG per the Note.  libtiff is available
+from ftp://ftp.sgi.com/graphics/tiff/.
+
+
+ARCHIVE LOCATIONS
+=================
+
+The "official" archive site for this software is ftp.uu.net (Internet
+address 192.48.96.9).  The most recent released version can always be found
+there in directory graphics/jpeg.  This particular version will be archived
+as ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz.  If you don't have
+direct Internet access, UUNET's archives are also available via UUCP; contact
+help@uunet.uu.net for information on retrieving files that way.
+
+Numerous Internet sites maintain copies of the UUNET files.  However, only
+ftp.uu.net is guaranteed to have the latest official version.
+
+You can also obtain this software in DOS-compatible "zip" archive format from
+the SimTel archives (ftp://ftp.simtel.net/pub/simtelnet/msdos/graphics/), or
+on CompuServe in the Graphics Support forum (GO CIS:GRAPHSUP), library 12
+"JPEG Tools".  Again, these versions may sometimes lag behind the ftp.uu.net
+release.
+
+The JPEG FAQ (Frequently Asked Questions) article is a useful source of
+general information about JPEG.  It is updated constantly and therefore is
+not included in this distribution.  The FAQ is posted every two weeks to
+Usenet newsgroups comp.graphics.misc, news.answers, and other groups.
+It is available on the World Wide Web at http://www.faqs.org/faqs/jpeg-faq/
+and other news.answers archive sites, including the official news.answers
+archive at rtfm.mit.edu: ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/.
+If you don't have Web or FTP access, send e-mail to mail-server@rtfm.mit.edu
+with body
+	send usenet/news.answers/jpeg-faq/part1
+	send usenet/news.answers/jpeg-faq/part2
+
+
+RELATED SOFTWARE
+================
+
+Numerous viewing and image manipulation programs now support JPEG.  (Quite a
+few of them use this library to do so.)  The JPEG FAQ described above lists
+some of the more popular free and shareware viewers, and tells where to
+obtain them on Internet.
+
+If you are on a Unix machine, we highly recommend Jef Poskanzer's free
+PBMPLUS software, which provides many useful operations on PPM-format image
+files.  In particular, it can convert PPM images to and from a wide range of
+other formats, thus making cjpeg/djpeg considerably more useful.  The latest
+version is distributed by the NetPBM group, and is available from numerous
+sites, notably ftp://wuarchive.wustl.edu/graphics/graphics/packages/NetPBM/.
+Unfortunately PBMPLUS/NETPBM is not nearly as portable as the IJG software is;
+you are likely to have difficulty making it work on any non-Unix machine.
+
+A different free JPEG implementation, written by the PVRG group at Stanford,
+is available from ftp://havefun.stanford.edu/pub/jpeg/.  This program
+is designed for research and experimentation rather than production use;
+it is slower, harder to use, and less portable than the IJG code, but it
+is easier to read and modify.  Also, the PVRG code supports lossless JPEG,
+which we do not.  (On the other hand, it doesn't do progressive JPEG.)
+
+
+FILE FORMAT WARS
+================
+
+Some JPEG programs produce files that are not compatible with our library.
+The root of the problem is that the ISO JPEG committee failed to specify a
+concrete file format.  Some vendors "filled in the blanks" on their own,
+creating proprietary formats that no one else could read.  (For example, none
+of the early commercial JPEG implementations for the Macintosh were able to
+exchange compressed files.)
+
+The file format we have adopted is called JFIF (see REFERENCES).  This format
+has been agreed to by a number of major commercial JPEG vendors, and it has
+become the de facto standard.  JFIF is a minimal or "low end" representation.
+We recommend the use of TIFF/JPEG (TIFF revision 6.0 as modified by TIFF
+Technical Note #2) for "high end" applications that need to record a lot of
+additional data about an image.  TIFF/JPEG is fairly new and not yet widely
+supported, unfortunately.
+
+The upcoming JPEG Part 3 standard defines a file format called SPIFF.
+SPIFF is interoperable with JFIF, in the sense that most JFIF decoders should
+be able to read the most common variant of SPIFF.  SPIFF has some technical
+advantages over JFIF, but its major claim to fame is simply that it is an
+official standard rather than an informal one.  At this point it is unclear
+whether SPIFF will supersede JFIF or whether JFIF will remain the de-facto
+standard.  IJG intends to support SPIFF once the standard is frozen, but we
+have not decided whether it should become our default output format or not.
+(In any case, our decoder will remain capable of reading JFIF indefinitely.)
+
+Various proprietary file formats incorporating JPEG compression also exist.
+We have little or no sympathy for the existence of these formats.  Indeed,
+one of the original reasons for developing this free software was to help
+force convergence on common, open format standards for JPEG files.  Don't
+use a proprietary file format!
+
+
+TO DO
+=====
+
+The major thrust for v7 will probably be improvement of visual quality.
+The current method for scaling the quantization tables is known not to be
+very good at low Q values.  We also intend to investigate block boundary
+smoothing, "poor man's variable quantization", and other means of improving
+quality-vs-file-size performance without sacrificing compatibility.
+
+In future versions, we are considering supporting some of the upcoming JPEG
+Part 3 extensions --- principally, variable quantization and the SPIFF file
+format.
+
+As always, speeding things up is of great interest.
+
+Please send bug reports, offers of help, etc. to jpeg-info@uunet.uu.net.
diff --git a/code/jpeg-6/jcapimin.c b/code/jpeg-6/jcapimin.c
new file mode 100755
index 0000000..6d603e7
--- /dev/null
+++ b/code/jpeg-6/jcapimin.c
@@ -0,0 +1,228 @@
+/*

+ * jcapimin.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface code for the compression half

+ * of the JPEG library.  These are the "minimum" API routines that may be

+ * needed in either the normal full-compression case or the transcoding-only

+ * case.

+ *

+ * Most of the routines intended to be called directly by an application

+ * are in this file or in jcapistd.c.  But also see jcparam.c for

+ * parameter-setup helper routines, jcomapi.c for routines shared by

+ * compression and decompression, and jctrans.c for the transcoding case.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Initialization of a JPEG compression object.

+ * The error manager must already be set up (in case memory manager fails).

+ */

+

+GLOBAL void

+jpeg_create_compress (j_compress_ptr cinfo)

+{

+  int i;

+

+  /* For debugging purposes, zero the whole master structure.

+   * But error manager pointer is already there, so save and restore it.

+   */

+  {

+    struct jpeg_error_mgr * err = cinfo->err;

+    MEMZERO(cinfo, SIZEOF(struct jpeg_compress_struct));

+    cinfo->err = err;

+  }

+  cinfo->is_decompressor = FALSE;

+

+  /* Initialize a memory manager instance for this object */

+  jinit_memory_mgr((j_common_ptr) cinfo);

+

+  /* Zero out pointers to permanent structures. */

+  cinfo->progress = NULL;

+  cinfo->dest = NULL;

+

+  cinfo->comp_info = NULL;

+

+  for (i = 0; i < NUM_QUANT_TBLS; i++)

+    cinfo->quant_tbl_ptrs[i] = NULL;

+

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    cinfo->dc_huff_tbl_ptrs[i] = NULL;

+    cinfo->ac_huff_tbl_ptrs[i] = NULL;

+  }

+

+  cinfo->input_gamma = 1.0;	/* in case application forgets */

+

+  /* OK, I'm ready */

+  cinfo->global_state = CSTATE_START;

+}

+

+

+/*

+ * Destruction of a JPEG compression object

+ */

+

+GLOBAL void

+jpeg_destroy_compress (j_compress_ptr cinfo)

+{

+  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Abort processing of a JPEG compression operation,

+ * but don't destroy the object itself.

+ */

+

+GLOBAL void

+jpeg_abort_compress (j_compress_ptr cinfo)

+{

+  jpeg_abort((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Forcibly suppress or un-suppress all quantization and Huffman tables.

+ * Marks all currently defined tables as already written (if suppress)

+ * or not written (if !suppress).  This will control whether they get emitted

+ * by a subsequent jpeg_start_compress call.

+ *

+ * This routine is exported for use by applications that want to produce

+ * abbreviated JPEG datastreams.  It logically belongs in jcparam.c, but

+ * since it is called by jpeg_start_compress, we put it here --- otherwise

+ * jcparam.o would be linked whether the application used it or not.

+ */

+

+GLOBAL void

+jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)

+{

+  int i;

+  JQUANT_TBL * qtbl;

+  JHUFF_TBL * htbl;

+

+  for (i = 0; i < NUM_QUANT_TBLS; i++) {

+    if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)

+      qtbl->sent_table = suppress;

+  }

+

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)

+      htbl->sent_table = suppress;

+    if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)

+      htbl->sent_table = suppress;

+  }

+}

+

+

+/*

+ * Finish JPEG compression.

+ *

+ * If a multipass operating mode was selected, this may do a great deal of

+ * work including most of the actual output.

+ */

+

+GLOBAL void

+jpeg_finish_compress (j_compress_ptr cinfo)

+{

+  JDIMENSION iMCU_row;

+

+  if (cinfo->global_state == CSTATE_SCANNING ||

+      cinfo->global_state == CSTATE_RAW_OK) {

+    /* Terminate first pass */

+    if (cinfo->next_scanline < cinfo->image_height)

+      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);

+    (*cinfo->master->finish_pass) (cinfo);

+  } else if (cinfo->global_state != CSTATE_WRCOEFS)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  /* Perform any remaining passes */

+  while (! cinfo->master->is_last_pass) {

+    (*cinfo->master->prepare_for_pass) (cinfo);

+    for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {

+      if (cinfo->progress != NULL) {

+	cinfo->progress->pass_counter = (long) iMCU_row;

+	cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;

+	(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+      }

+      /* We bypass the main controller and invoke coef controller directly;

+       * all work is being done from the coefficient buffer.

+       */

+      if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))

+	ERREXIT(cinfo, JERR_CANT_SUSPEND);

+    }

+    (*cinfo->master->finish_pass) (cinfo);

+  }

+  /* Write EOI, do final cleanup */

+  (*cinfo->marker->write_file_trailer) (cinfo);

+  (*cinfo->dest->term_destination) (cinfo);

+  /* We can use jpeg_abort to release memory and reset global_state */

+  jpeg_abort((j_common_ptr) cinfo);

+}

+

+

+/*

+ * Write a special marker.

+ * This is only recommended for writing COM or APPn markers.

+ * Must be called after jpeg_start_compress() and before

+ * first call to jpeg_write_scanlines() or jpeg_write_raw_data().

+ */

+

+GLOBAL void

+jpeg_write_marker (j_compress_ptr cinfo, int marker,

+		   const JOCTET *dataptr, unsigned int datalen)

+{

+  if (cinfo->next_scanline != 0 ||

+      (cinfo->global_state != CSTATE_SCANNING &&

+       cinfo->global_state != CSTATE_RAW_OK &&

+       cinfo->global_state != CSTATE_WRCOEFS))

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  (*cinfo->marker->write_any_marker) (cinfo, marker, dataptr, datalen);

+}

+

+

+/*

+ * Alternate compression function: just write an abbreviated table file.

+ * Before calling this, all parameters and a data destination must be set up.

+ *

+ * To produce a pair of files containing abbreviated tables and abbreviated

+ * image data, one would proceed as follows:

+ *

+ *		initialize JPEG object

+ *		set JPEG parameters

+ *		set destination to table file

+ *		jpeg_write_tables(cinfo);

+ *		set destination to image file

+ *		jpeg_start_compress(cinfo, FALSE);

+ *		write data...

+ *		jpeg_finish_compress(cinfo);

+ *

+ * jpeg_write_tables has the side effect of marking all tables written

+ * (same as jpeg_suppress_tables(..., TRUE)).  Thus a subsequent start_compress

+ * will not re-emit the tables unless it is passed write_all_tables=TRUE.

+ */

+

+GLOBAL void

+jpeg_write_tables (j_compress_ptr cinfo)

+{

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  /* (Re)initialize error mgr and destination modules */

+  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);

+  (*cinfo->dest->init_destination) (cinfo);

+  /* Initialize the marker writer ... bit of a crock to do it here. */

+  jinit_marker_writer(cinfo);

+  /* Write them tables! */

+  (*cinfo->marker->write_tables_only) (cinfo);

+  /* And clean up. */

+  (*cinfo->dest->term_destination) (cinfo);

+  /* We can use jpeg_abort to release memory. */

+  jpeg_abort((j_common_ptr) cinfo);

+}

diff --git a/code/jpeg-6/jcapistd.c b/code/jpeg-6/jcapistd.c
new file mode 100755
index 0000000..8c3721d
--- /dev/null
+++ b/code/jpeg-6/jcapistd.c
@@ -0,0 +1,161 @@
+/*

+ * jcapistd.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface code for the compression half

+ * of the JPEG library.  These are the "standard" API routines that are

+ * used in the normal full-compression case.  They are not used by a

+ * transcoding-only application.  Note that if an application links in

+ * jpeg_start_compress, it will end up linking in the entire compressor.

+ * We thus must separate this file from jcapimin.c to avoid linking the

+ * whole compression library into a transcoder.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Compression initialization.

+ * Before calling this, all parameters and a data destination must be set up.

+ *

+ * We require a write_all_tables parameter as a failsafe check when writing

+ * multiple datastreams from the same compression object.  Since prior runs

+ * will have left all the tables marked sent_table=TRUE, a subsequent run

+ * would emit an abbreviated stream (no tables) by default.  This may be what

+ * is wanted, but for safety's sake it should not be the default behavior:

+ * programmers should have to make a deliberate choice to emit abbreviated

+ * images.  Therefore the documentation and examples should encourage people

+ * to pass write_all_tables=TRUE; then it will take active thought to do the

+ * wrong thing.

+ */

+

+GLOBAL void

+jpeg_start_compress (j_compress_ptr cinfo, boolean write_all_tables)

+{

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  if (write_all_tables)

+    jpeg_suppress_tables(cinfo, FALSE);	/* mark all tables to be written */

+

+  /* (Re)initialize error mgr and destination modules */

+  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);

+  (*cinfo->dest->init_destination) (cinfo);

+  /* Perform master selection of active modules */

+  jinit_compress_master(cinfo);

+  /* Set up for the first pass */

+  (*cinfo->master->prepare_for_pass) (cinfo);

+  /* Ready for application to drive first pass through jpeg_write_scanlines

+   * or jpeg_write_raw_data.

+   */

+  cinfo->next_scanline = 0;

+  cinfo->global_state = (cinfo->raw_data_in ? CSTATE_RAW_OK : CSTATE_SCANNING);

+}

+

+

+/*

+ * Write some scanlines of data to the JPEG compressor.

+ *

+ * The return value will be the number of lines actually written.

+ * This should be less than the supplied num_lines only in case that

+ * the data destination module has requested suspension of the compressor,

+ * or if more than image_height scanlines are passed in.

+ *

+ * Note: we warn about excess calls to jpeg_write_scanlines() since

+ * this likely signals an application programmer error.  However,

+ * excess scanlines passed in the last valid call are *silently* ignored,

+ * so that the application need not adjust num_lines for end-of-image

+ * when using a multiple-scanline buffer.

+ */

+

+GLOBAL JDIMENSION

+jpeg_write_scanlines (j_compress_ptr cinfo, JSAMPARRAY scanlines,

+		      JDIMENSION num_lines)

+{

+  JDIMENSION row_ctr, rows_left;

+

+  if (cinfo->global_state != CSTATE_SCANNING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  if (cinfo->next_scanline >= cinfo->image_height)

+    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);

+

+  /* Call progress monitor hook if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->pass_counter = (long) cinfo->next_scanline;

+    cinfo->progress->pass_limit = (long) cinfo->image_height;

+    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+  }

+

+  /* Give master control module another chance if this is first call to

+   * jpeg_write_scanlines.  This lets output of the frame/scan headers be

+   * delayed so that application can write COM, etc, markers between

+   * jpeg_start_compress and jpeg_write_scanlines.

+   */

+  if (cinfo->master->call_pass_startup)

+    (*cinfo->master->pass_startup) (cinfo);

+

+  /* Ignore any extra scanlines at bottom of image. */

+  rows_left = cinfo->image_height - cinfo->next_scanline;

+  if (num_lines > rows_left)

+    num_lines = rows_left;

+

+  row_ctr = 0;

+  (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, num_lines);

+  cinfo->next_scanline += row_ctr;

+  return row_ctr;

+}

+

+

+/*

+ * Alternate entry point to write raw data.

+ * Processes exactly one iMCU row per call, unless suspended.

+ */

+

+GLOBAL JDIMENSION

+jpeg_write_raw_data (j_compress_ptr cinfo, JSAMPIMAGE data,

+		     JDIMENSION num_lines)

+{

+  JDIMENSION lines_per_iMCU_row;

+

+  if (cinfo->global_state != CSTATE_RAW_OK)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  if (cinfo->next_scanline >= cinfo->image_height) {

+    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);

+    return 0;

+  }

+

+  /* Call progress monitor hook if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->pass_counter = (long) cinfo->next_scanline;

+    cinfo->progress->pass_limit = (long) cinfo->image_height;

+    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+  }

+

+  /* Give master control module another chance if this is first call to

+   * jpeg_write_raw_data.  This lets output of the frame/scan headers be

+   * delayed so that application can write COM, etc, markers between

+   * jpeg_start_compress and jpeg_write_raw_data.

+   */

+  if (cinfo->master->call_pass_startup)

+    (*cinfo->master->pass_startup) (cinfo);

+

+  /* Verify that at least one iMCU row has been passed. */

+  lines_per_iMCU_row = cinfo->max_v_samp_factor * DCTSIZE;

+  if (num_lines < lines_per_iMCU_row)

+    ERREXIT(cinfo, JERR_BUFFER_SIZE);

+

+  /* Directly compress the row. */

+  if (! (*cinfo->coef->compress_data) (cinfo, data)) {

+    /* If compressor did not consume the whole row, suspend processing. */

+    return 0;

+  }

+

+  /* OK, we processed one iMCU row. */

+  cinfo->next_scanline += lines_per_iMCU_row;

+  return lines_per_iMCU_row;

+}

diff --git a/code/jpeg-6/jccoefct.c b/code/jpeg-6/jccoefct.c
new file mode 100755
index 0000000..9a33f7a
--- /dev/null
+++ b/code/jpeg-6/jccoefct.c
@@ -0,0 +1,448 @@
+/*

+ * jccoefct.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the coefficient buffer controller for compression.

+ * This controller is the top level of the JPEG compressor proper.

+ * The coefficient buffer lies between forward-DCT and entropy encoding steps.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* We use a full-image coefficient buffer when doing Huffman optimization,

+ * and also for writing multiple-scan JPEG files.  In all cases, the DCT

+ * step is run during the first pass, and subsequent passes need only read

+ * the buffered coefficients.

+ */

+#ifdef ENTROPY_OPT_SUPPORTED

+#define FULL_COEF_BUFFER_SUPPORTED

+#else

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+#define FULL_COEF_BUFFER_SUPPORTED

+#endif

+#endif

+

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_c_coef_controller pub; /* public fields */

+

+  JDIMENSION iMCU_row_num;	/* iMCU row # within image */

+  JDIMENSION mcu_ctr;		/* counts MCUs processed in current row */

+  int MCU_vert_offset;		/* counts MCU rows within iMCU row */

+  int MCU_rows_per_iMCU_row;	/* number of such rows needed */

+

+  /* For single-pass compression, it's sufficient to buffer just one MCU

+   * (although this may prove a bit slow in practice).  We allocate a

+   * workspace of C_MAX_BLOCKS_IN_MCU coefficient blocks, and reuse it for each

+   * MCU constructed and sent.  (On 80x86, the workspace is FAR even though

+   * it's not really very big; this is to keep the module interfaces unchanged

+   * when a large coefficient buffer is necessary.)

+   * In multi-pass modes, this array points to the current MCU's blocks

+   * within the virtual arrays.

+   */

+  JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];

+

+  /* In multi-pass modes, we need a virtual block array for each component. */

+  jvirt_barray_ptr whole_image[MAX_COMPONENTS];

+} my_coef_controller;

+

+typedef my_coef_controller * my_coef_ptr;

+

+

+/* Forward declarations */

+METHODDEF boolean compress_data

+    JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));

+#ifdef FULL_COEF_BUFFER_SUPPORTED

+METHODDEF boolean compress_first_pass

+    JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));

+METHODDEF boolean compress_output

+    JPP((j_compress_ptr cinfo, JSAMPIMAGE input_buf));

+#endif

+

+

+LOCAL void

+start_iMCU_row (j_compress_ptr cinfo)

+/* Reset within-iMCU-row counters for a new row */

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  /* In an interleaved scan, an MCU row is the same as an iMCU row.

+   * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.

+   * But at the bottom of the image, process only what's left.

+   */

+  if (cinfo->comps_in_scan > 1) {

+    coef->MCU_rows_per_iMCU_row = 1;

+  } else {

+    if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1))

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;

+    else

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;

+  }

+

+  coef->mcu_ctr = 0;

+  coef->MCU_vert_offset = 0;

+}

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  coef->iMCU_row_num = 0;

+  start_iMCU_row(cinfo);

+

+  switch (pass_mode) {

+  case JBUF_PASS_THRU:

+    if (coef->whole_image[0] != NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    coef->pub.compress_data = compress_data;

+    break;

+#ifdef FULL_COEF_BUFFER_SUPPORTED

+  case JBUF_SAVE_AND_PASS:

+    if (coef->whole_image[0] == NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    coef->pub.compress_data = compress_first_pass;

+    break;

+  case JBUF_CRANK_DEST:

+    if (coef->whole_image[0] == NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    coef->pub.compress_data = compress_output;

+    break;

+#endif

+  default:

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    break;

+  }

+}

+

+

+/*

+ * Process some data in the single-pass case.

+ * We process the equivalent of one fully interleaved MCU row ("iMCU" row)

+ * per call, ie, v_samp_factor block rows for each component in the image.

+ * Returns TRUE if the iMCU row is completed, FALSE if suspended.

+ *

+ * NB: input_buf contains a plane for each component in image.

+ * For single pass, this is the same as the components in the scan.

+ */

+

+METHODDEF boolean

+compress_data (j_compress_ptr cinfo, JSAMPIMAGE input_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION MCU_col_num;	/* index of current MCU within row */

+  JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  int blkn, bi, ci, yindex, yoffset, blockcnt;

+  JDIMENSION ypos, xpos;

+  jpeg_component_info *compptr;

+

+  /* Loop to write as much as one whole iMCU row */

+  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;

+       yoffset++) {

+    for (MCU_col_num = coef->mcu_ctr; MCU_col_num <= last_MCU_col;

+	 MCU_col_num++) {

+      /* Determine where data comes from in input_buf and do the DCT thing.

+       * Each call on forward_DCT processes a horizontal row of DCT blocks

+       * as wide as an MCU; we rely on having allocated the MCU_buffer[] blocks

+       * sequentially.  Dummy blocks at the right or bottom edge are filled in

+       * specially.  The data in them does not matter for image reconstruction,

+       * so we fill them with values that will encode to the smallest amount of

+       * data, viz: all zeroes in the AC entries, DC entries equal to previous

+       * block's DC value.  (Thanks to Thomas Kinsman for this idea.)

+       */

+      blkn = 0;

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+	compptr = cinfo->cur_comp_info[ci];

+	blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width

+						: compptr->last_col_width;

+	xpos = MCU_col_num * compptr->MCU_sample_width;

+	ypos = yoffset * DCTSIZE; /* ypos == (yoffset+yindex) * DCTSIZE */

+	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {

+	  if (coef->iMCU_row_num < last_iMCU_row ||

+	      yoffset+yindex < compptr->last_row_height) {

+	    (*cinfo->fdct->forward_DCT) (cinfo, compptr,

+					 input_buf[ci], coef->MCU_buffer[blkn],

+					 ypos, xpos, (JDIMENSION) blockcnt);

+	    if (blockcnt < compptr->MCU_width) {

+	      /* Create some dummy blocks at the right edge of the image. */

+	      jzero_far((void FAR *) coef->MCU_buffer[blkn + blockcnt],

+			(compptr->MCU_width - blockcnt) * SIZEOF(JBLOCK));

+	      for (bi = blockcnt; bi < compptr->MCU_width; bi++) {

+		coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn+bi-1][0][0];

+	      }

+	    }

+	  } else {

+	    /* Create a row of dummy blocks at the bottom of the image. */

+	    jzero_far((void FAR *) coef->MCU_buffer[blkn],

+		      compptr->MCU_width * SIZEOF(JBLOCK));

+	    for (bi = 0; bi < compptr->MCU_width; bi++) {

+	      coef->MCU_buffer[blkn+bi][0][0] = coef->MCU_buffer[blkn-1][0][0];

+	    }

+	  }

+	  blkn += compptr->MCU_width;

+	  ypos += DCTSIZE;

+	}

+      }

+      /* Try to write the MCU.  In event of a suspension failure, we will

+       * re-DCT the MCU on restart (a bit inefficient, could be fixed...)

+       */

+      if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) {

+	/* Suspension forced; update state counters and exit */

+	coef->MCU_vert_offset = yoffset;

+	coef->mcu_ctr = MCU_col_num;

+	return FALSE;

+      }

+    }

+    /* Completed an MCU row, but perhaps not an iMCU row */

+    coef->mcu_ctr = 0;

+  }

+  /* Completed the iMCU row, advance counters for next one */

+  coef->iMCU_row_num++;

+  start_iMCU_row(cinfo);

+  return TRUE;

+}

+

+

+#ifdef FULL_COEF_BUFFER_SUPPORTED

+

+/*

+ * Process some data in the first pass of a multi-pass case.

+ * We process the equivalent of one fully interleaved MCU row ("iMCU" row)

+ * per call, ie, v_samp_factor block rows for each component in the image.

+ * This amount of data is read from the source buffer, DCT'd and quantized,

+ * and saved into the virtual arrays.  We also generate suitable dummy blocks

+ * as needed at the right and lower edges.  (The dummy blocks are constructed

+ * in the virtual arrays, which have been padded appropriately.)  This makes

+ * it possible for subsequent passes not to worry about real vs. dummy blocks.

+ *

+ * We must also emit the data to the entropy encoder.  This is conveniently

+ * done by calling compress_output() after we've loaded the current strip

+ * of the virtual arrays.

+ *

+ * NB: input_buf contains a plane for each component in image.  All

+ * components are DCT'd and loaded into the virtual arrays in this pass.

+ * However, it may be that only a subset of the components are emitted to

+ * the entropy encoder during this first pass; be careful about looking

+ * at the scan-dependent variables (MCU dimensions, etc).

+ */

+

+METHODDEF boolean

+compress_first_pass (j_compress_ptr cinfo, JSAMPIMAGE input_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  JDIMENSION blocks_across, MCUs_across, MCUindex;

+  int bi, ci, h_samp_factor, block_row, block_rows, ndummy;

+  JCOEF lastDC;

+  jpeg_component_info *compptr;

+  JBLOCKARRAY buffer;

+  JBLOCKROW thisblockrow, lastblockrow;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Align the virtual buffer for this component. */

+    buffer = (*cinfo->mem->access_virt_barray)

+      ((j_common_ptr) cinfo, coef->whole_image[ci],

+       coef->iMCU_row_num * compptr->v_samp_factor,

+       (JDIMENSION) compptr->v_samp_factor, TRUE);

+    /* Count non-dummy DCT block rows in this iMCU row. */

+    if (coef->iMCU_row_num < last_iMCU_row)

+      block_rows = compptr->v_samp_factor;

+    else {

+      /* NB: can't use last_row_height here, since may not be set! */

+      block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);

+      if (block_rows == 0) block_rows = compptr->v_samp_factor;

+    }

+    blocks_across = compptr->width_in_blocks;

+    h_samp_factor = compptr->h_samp_factor;

+    /* Count number of dummy blocks to be added at the right margin. */

+    ndummy = (int) (blocks_across % h_samp_factor);

+    if (ndummy > 0)

+      ndummy = h_samp_factor - ndummy;

+    /* Perform DCT for all non-dummy blocks in this iMCU row.  Each call

+     * on forward_DCT processes a complete horizontal row of DCT blocks.

+     */

+    for (block_row = 0; block_row < block_rows; block_row++) {

+      thisblockrow = buffer[block_row];

+      (*cinfo->fdct->forward_DCT) (cinfo, compptr,

+				   input_buf[ci], thisblockrow,

+				   (JDIMENSION) (block_row * DCTSIZE),

+				   (JDIMENSION) 0, blocks_across);

+      if (ndummy > 0) {

+	/* Create dummy blocks at the right edge of the image. */

+	thisblockrow += blocks_across; /* => first dummy block */

+	jzero_far((void FAR *) thisblockrow, ndummy * SIZEOF(JBLOCK));

+	lastDC = thisblockrow[-1][0];

+	for (bi = 0; bi < ndummy; bi++) {

+	  thisblockrow[bi][0] = lastDC;

+	}

+      }

+    }

+    /* If at end of image, create dummy block rows as needed.

+     * The tricky part here is that within each MCU, we want the DC values

+     * of the dummy blocks to match the last real block's DC value.

+     * This squeezes a few more bytes out of the resulting file...

+     */

+    if (coef->iMCU_row_num == last_iMCU_row) {

+      blocks_across += ndummy;	/* include lower right corner */

+      MCUs_across = blocks_across / h_samp_factor;

+      for (block_row = block_rows; block_row < compptr->v_samp_factor;

+	   block_row++) {

+	thisblockrow = buffer[block_row];

+	lastblockrow = buffer[block_row-1];

+	jzero_far((void FAR *) thisblockrow,

+		  (size_t) (blocks_across * SIZEOF(JBLOCK)));

+	for (MCUindex = 0; MCUindex < MCUs_across; MCUindex++) {

+	  lastDC = lastblockrow[h_samp_factor-1][0];

+	  for (bi = 0; bi < h_samp_factor; bi++) {

+	    thisblockrow[bi][0] = lastDC;

+	  }

+	  thisblockrow += h_samp_factor; /* advance to next MCU in row */

+	  lastblockrow += h_samp_factor;

+	}

+      }

+    }

+  }

+  /* NB: compress_output will increment iMCU_row_num if successful.

+   * A suspension return will result in redoing all the work above next time.

+   */

+

+  /* Emit data to the entropy encoder, sharing code with subsequent passes */

+  return compress_output(cinfo, input_buf);

+}

+

+

+/*

+ * Process some data in subsequent passes of a multi-pass case.

+ * We process the equivalent of one fully interleaved MCU row ("iMCU" row)

+ * per call, ie, v_samp_factor block rows for each component in the scan.

+ * The data is obtained from the virtual arrays and fed to the entropy coder.

+ * Returns TRUE if the iMCU row is completed, FALSE if suspended.

+ *

+ * NB: input_buf is ignored; it is likely to be a NULL pointer.

+ */

+

+METHODDEF boolean

+compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION MCU_col_num;	/* index of current MCU within row */

+  int blkn, ci, xindex, yindex, yoffset;

+  JDIMENSION start_col;

+  JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];

+  JBLOCKROW buffer_ptr;

+  jpeg_component_info *compptr;

+

+  /* Align the virtual buffers for the components used in this scan.

+   * NB: during first pass, this is safe only because the buffers will

+   * already be aligned properly, so jmemmgr.c won't need to do any I/O.

+   */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    buffer[ci] = (*cinfo->mem->access_virt_barray)

+      ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],

+       coef->iMCU_row_num * compptr->v_samp_factor,

+       (JDIMENSION) compptr->v_samp_factor, FALSE);

+  }

+

+  /* Loop to process one whole iMCU row */

+  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;

+       yoffset++) {

+    for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;

+	 MCU_col_num++) {

+      /* Construct list of pointers to DCT blocks belonging to this MCU */

+      blkn = 0;			/* index of current DCT block within MCU */

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+	compptr = cinfo->cur_comp_info[ci];

+	start_col = MCU_col_num * compptr->MCU_width;

+	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {

+	  buffer_ptr = buffer[ci][yindex+yoffset] + start_col;

+	  for (xindex = 0; xindex < compptr->MCU_width; xindex++) {

+	    coef->MCU_buffer[blkn++] = buffer_ptr++;

+	  }

+	}

+      }

+      /* Try to write the MCU. */

+      if (! (*cinfo->entropy->encode_mcu) (cinfo, coef->MCU_buffer)) {

+	/* Suspension forced; update state counters and exit */

+	coef->MCU_vert_offset = yoffset;

+	coef->mcu_ctr = MCU_col_num;

+	return FALSE;

+      }

+    }

+    /* Completed an MCU row, but perhaps not an iMCU row */

+    coef->mcu_ctr = 0;

+  }

+  /* Completed the iMCU row, advance counters for next one */

+  coef->iMCU_row_num++;

+  start_iMCU_row(cinfo);

+  return TRUE;

+}

+

+#endif /* FULL_COEF_BUFFER_SUPPORTED */

+

+

+/*

+ * Initialize coefficient buffer controller.

+ */

+

+GLOBAL void

+jinit_c_coef_controller (j_compress_ptr cinfo, boolean need_full_buffer)

+{

+  my_coef_ptr coef;

+

+  coef = (my_coef_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_coef_controller));

+  cinfo->coef = (struct jpeg_c_coef_controller *) coef;

+  coef->pub.start_pass = start_pass_coef;

+

+  /* Create the coefficient buffer. */

+  if (need_full_buffer) {

+#ifdef FULL_COEF_BUFFER_SUPPORTED

+    /* Allocate a full-image virtual array for each component, */

+    /* padded to a multiple of samp_factor DCT blocks in each direction. */

+    int ci;

+    jpeg_component_info *compptr;

+

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      coef->whole_image[ci] = (*cinfo->mem->request_virt_barray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,

+	 (JDIMENSION) jround_up((long) compptr->width_in_blocks,

+				(long) compptr->h_samp_factor),

+	 (JDIMENSION) jround_up((long) compptr->height_in_blocks,

+				(long) compptr->v_samp_factor),

+	 (JDIMENSION) compptr->v_samp_factor);

+    }

+#else

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+#endif

+  } else {

+    /* We only need a single-MCU buffer. */

+    JBLOCKROW buffer;

+    int i;

+

+    buffer = (JBLOCKROW)

+      (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));

+    for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {

+      coef->MCU_buffer[i] = buffer + i;

+    }

+    coef->whole_image[0] = NULL; /* flag for no virtual arrays */

+  }

+}

diff --git a/code/jpeg-6/jccolor.c b/code/jpeg-6/jccolor.c
new file mode 100755
index 0000000..1f0f760
--- /dev/null
+++ b/code/jpeg-6/jccolor.c
@@ -0,0 +1,459 @@
+/*

+ * jccolor.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains input colorspace conversion routines.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_color_converter pub; /* public fields */

+

+  /* Private state for RGB->YCC conversion */

+  INT32 * rgb_ycc_tab;		/* => table for RGB to YCbCr conversion */

+} my_color_converter;

+

+typedef my_color_converter * my_cconvert_ptr;

+

+

+/**************** RGB -> YCbCr conversion: most common case **************/

+

+/*

+ * YCbCr is defined per CCIR 601-1, except that Cb and Cr are

+ * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.

+ * The conversion equations to be implemented are therefore

+ *	Y  =  0.29900 * R + 0.58700 * G + 0.11400 * B

+ *	Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B  + CENTERJSAMPLE

+ *	Cr =  0.50000 * R - 0.41869 * G - 0.08131 * B  + CENTERJSAMPLE

+ * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)

+ * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2,

+ * rather than CENTERJSAMPLE, for Cb and Cr.  This gave equal positive and

+ * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0)

+ * were not represented exactly.  Now we sacrifice exact representation of

+ * maximum red and maximum blue in order to get exact grayscales.

+ *

+ * To avoid floating-point arithmetic, we represent the fractional constants

+ * as integers scaled up by 2^16 (about 4 digits precision); we have to divide

+ * the products by 2^16, with appropriate rounding, to get the correct answer.

+ *

+ * For even more speed, we avoid doing any multiplications in the inner loop

+ * by precalculating the constants times R,G,B for all possible values.

+ * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);

+ * for 12-bit samples it is still acceptable.  It's not very reasonable for

+ * 16-bit samples, but if you want lossless storage you shouldn't be changing

+ * colorspace anyway.

+ * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included

+ * in the tables to save adding them separately in the inner loop.

+ */

+

+#define SCALEBITS	16	/* speediest right-shift on some machines */

+#define CBCR_OFFSET	((INT32) CENTERJSAMPLE << SCALEBITS)

+#define ONE_HALF	((INT32) 1 << (SCALEBITS-1))

+#define FIX(x)		((INT32) ((x) * (1L<<SCALEBITS) + 0.5))

+

+/* We allocate one big table and divide it up into eight parts, instead of

+ * doing eight alloc_small requests.  This lets us use a single table base

+ * address, which can be held in a register in the inner loops on many

+ * machines (more than can hold all eight addresses, anyway).

+ */

+

+#define R_Y_OFF		0			/* offset to R => Y section */

+#define G_Y_OFF		(1*(MAXJSAMPLE+1))	/* offset to G => Y section */

+#define B_Y_OFF		(2*(MAXJSAMPLE+1))	/* etc. */

+#define R_CB_OFF	(3*(MAXJSAMPLE+1))

+#define G_CB_OFF	(4*(MAXJSAMPLE+1))

+#define B_CB_OFF	(5*(MAXJSAMPLE+1))

+#define R_CR_OFF	B_CB_OFF		/* B=>Cb, R=>Cr are the same */

+#define G_CR_OFF	(6*(MAXJSAMPLE+1))

+#define B_CR_OFF	(7*(MAXJSAMPLE+1))

+#define TABLE_SIZE	(8*(MAXJSAMPLE+1))

+

+

+/*

+ * Initialize for RGB->YCC colorspace conversion.

+ */

+

+METHODDEF void

+rgb_ycc_start (j_compress_ptr cinfo)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  INT32 * rgb_ycc_tab;

+  INT32 i;

+

+  /* Allocate and fill in the conversion tables. */

+  cconvert->rgb_ycc_tab = rgb_ycc_tab = (INT32 *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(TABLE_SIZE * SIZEOF(INT32)));

+

+  for (i = 0; i <= MAXJSAMPLE; i++) {

+    rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i;

+    rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i;

+    rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i     + ONE_HALF;

+    rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i;

+    rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i;

+    /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr.

+     * This ensures that the maximum output will round to MAXJSAMPLE

+     * not MAXJSAMPLE+1, and thus that we don't have to range-limit.

+     */

+    rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i    + CBCR_OFFSET + ONE_HALF-1;

+/*  B=>Cb and R=>Cr tables are the same

+    rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i    + CBCR_OFFSET + ONE_HALF-1;

+*/

+    rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i;

+    rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i;

+  }

+}

+

+

+/*

+ * Convert some rows of samples to the JPEG colorspace.

+ *

+ * Note that we change from the application's interleaved-pixel format

+ * to our internal noninterleaved, one-plane-per-component format.

+ * The input buffer is therefore three times as wide as the output buffer.

+ *

+ * A starting row offset is provided only for the output buffer.  The caller

+ * can easily adjust the passed input_buf value to accommodate any row

+ * offset required on that side.

+ */

+

+METHODDEF void

+rgb_ycc_convert (j_compress_ptr cinfo,

+		 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+		 JDIMENSION output_row, int num_rows)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  register int r, g, b;

+  register INT32 * ctab = cconvert->rgb_ycc_tab;

+  register JSAMPROW inptr;

+  register JSAMPROW outptr0, outptr1, outptr2;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->image_width;

+

+  while (--num_rows >= 0) {

+    inptr = *input_buf++;

+    outptr0 = output_buf[0][output_row];

+    outptr1 = output_buf[1][output_row];

+    outptr2 = output_buf[2][output_row];

+    output_row++;

+    for (col = 0; col < num_cols; col++) {

+      r = GETJSAMPLE(inptr[RGB_RED]);

+      g = GETJSAMPLE(inptr[RGB_GREEN]);

+      b = GETJSAMPLE(inptr[RGB_BLUE]);

+      inptr += RGB_PIXELSIZE;

+      /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations

+       * must be too; we do not need an explicit range-limiting operation.

+       * Hence the value being shifted is never negative, and we don't

+       * need the general RIGHT_SHIFT macro.

+       */

+      /* Y */

+      outptr0[col] = (JSAMPLE)

+		((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])

+		 >> SCALEBITS);

+      /* Cb */

+      outptr1[col] = (JSAMPLE)

+		((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])

+		 >> SCALEBITS);

+      /* Cr */

+      outptr2[col] = (JSAMPLE)

+		((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])

+		 >> SCALEBITS);

+    }

+  }

+}

+

+

+/**************** Cases other than RGB -> YCbCr **************/

+

+

+/*

+ * Convert some rows of samples to the JPEG colorspace.

+ * This version handles RGB->grayscale conversion, which is the same

+ * as the RGB->Y portion of RGB->YCbCr.

+ * We assume rgb_ycc_start has been called (we only use the Y tables).

+ */

+

+METHODDEF void

+rgb_gray_convert (j_compress_ptr cinfo,

+		  JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+		  JDIMENSION output_row, int num_rows)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  register int r, g, b;

+  register INT32 * ctab = cconvert->rgb_ycc_tab;

+  register JSAMPROW inptr;

+  register JSAMPROW outptr;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->image_width;

+

+  while (--num_rows >= 0) {

+    inptr = *input_buf++;

+    outptr = output_buf[0][output_row];

+    output_row++;

+    for (col = 0; col < num_cols; col++) {

+      r = GETJSAMPLE(inptr[RGB_RED]);

+      g = GETJSAMPLE(inptr[RGB_GREEN]);

+      b = GETJSAMPLE(inptr[RGB_BLUE]);

+      inptr += RGB_PIXELSIZE;

+      /* Y */

+      outptr[col] = (JSAMPLE)

+		((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])

+		 >> SCALEBITS);

+    }

+  }

+}

+

+

+/*

+ * Convert some rows of samples to the JPEG colorspace.

+ * This version handles Adobe-style CMYK->YCCK conversion,

+ * where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same

+ * conversion as above, while passing K (black) unchanged.

+ * We assume rgb_ycc_start has been called.

+ */

+

+METHODDEF void

+cmyk_ycck_convert (j_compress_ptr cinfo,

+		   JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+		   JDIMENSION output_row, int num_rows)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  register int r, g, b;

+  register INT32 * ctab = cconvert->rgb_ycc_tab;

+  register JSAMPROW inptr;

+  register JSAMPROW outptr0, outptr1, outptr2, outptr3;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->image_width;

+

+  while (--num_rows >= 0) {

+    inptr = *input_buf++;

+    outptr0 = output_buf[0][output_row];

+    outptr1 = output_buf[1][output_row];

+    outptr2 = output_buf[2][output_row];

+    outptr3 = output_buf[3][output_row];

+    output_row++;

+    for (col = 0; col < num_cols; col++) {

+      r = MAXJSAMPLE - GETJSAMPLE(inptr[0]);

+      g = MAXJSAMPLE - GETJSAMPLE(inptr[1]);

+      b = MAXJSAMPLE - GETJSAMPLE(inptr[2]);

+      /* K passes through as-is */

+      outptr3[col] = inptr[3];	/* don't need GETJSAMPLE here */

+      inptr += 4;

+      /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations

+       * must be too; we do not need an explicit range-limiting operation.

+       * Hence the value being shifted is never negative, and we don't

+       * need the general RIGHT_SHIFT macro.

+       */

+      /* Y */

+      outptr0[col] = (JSAMPLE)

+		((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])

+		 >> SCALEBITS);

+      /* Cb */

+      outptr1[col] = (JSAMPLE)

+		((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])

+		 >> SCALEBITS);

+      /* Cr */

+      outptr2[col] = (JSAMPLE)

+		((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])

+		 >> SCALEBITS);

+    }

+  }

+}

+

+

+/*

+ * Convert some rows of samples to the JPEG colorspace.

+ * This version handles grayscale output with no conversion.

+ * The source can be either plain grayscale or YCbCr (since Y == gray).

+ */

+

+METHODDEF void

+grayscale_convert (j_compress_ptr cinfo,

+		   JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+		   JDIMENSION output_row, int num_rows)

+{

+  register JSAMPROW inptr;

+  register JSAMPROW outptr;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->image_width;

+  int instride = cinfo->input_components;

+

+  while (--num_rows >= 0) {

+    inptr = *input_buf++;

+    outptr = output_buf[0][output_row];

+    output_row++;

+    for (col = 0; col < num_cols; col++) {

+      outptr[col] = inptr[0];	/* don't need GETJSAMPLE() here */

+      inptr += instride;

+    }

+  }

+}

+

+

+/*

+ * Convert some rows of samples to the JPEG colorspace.

+ * This version handles multi-component colorspaces without conversion.

+ * We assume input_components == num_components.

+ */

+

+METHODDEF void

+null_convert (j_compress_ptr cinfo,

+	      JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+	      JDIMENSION output_row, int num_rows)

+{

+  register JSAMPROW inptr;

+  register JSAMPROW outptr;

+  register JDIMENSION col;

+  register int ci;

+  int nc = cinfo->num_components;

+  JDIMENSION num_cols = cinfo->image_width;

+

+  while (--num_rows >= 0) {

+    /* It seems fastest to make a separate pass for each component. */

+    for (ci = 0; ci < nc; ci++) {

+      inptr = *input_buf;

+      outptr = output_buf[ci][output_row];

+      for (col = 0; col < num_cols; col++) {

+	outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */

+	inptr += nc;

+      }

+    }

+    input_buf++;

+    output_row++;

+  }

+}

+

+

+/*

+ * Empty method for start_pass.

+ */

+

+METHODDEF void

+null_method (j_compress_ptr cinfo)

+{

+  /* no work needed */

+}

+

+

+/*

+ * Module initialization routine for input colorspace conversion.

+ */

+

+GLOBAL void

+jinit_color_converter (j_compress_ptr cinfo)

+{

+  my_cconvert_ptr cconvert;

+

+  cconvert = (my_cconvert_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_color_converter));

+  cinfo->cconvert = (struct jpeg_color_converter *) cconvert;

+  /* set start_pass to null method until we find out differently */

+  cconvert->pub.start_pass = null_method;

+

+  /* Make sure input_components agrees with in_color_space */

+  switch (cinfo->in_color_space) {

+  case JCS_GRAYSCALE:

+    if (cinfo->input_components != 1)

+      ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+    break;

+

+  case JCS_RGB:

+#if RGB_PIXELSIZE != 3

+    if (cinfo->input_components != RGB_PIXELSIZE)

+      ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+    break;

+#endif /* else share code with YCbCr */

+

+  case JCS_YCbCr:

+    if (cinfo->input_components != 3)

+      ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+    break;

+

+  case JCS_CMYK:

+  case JCS_YCCK:

+    if (cinfo->input_components != 4)

+      ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+    break;

+

+  default:			/* JCS_UNKNOWN can be anything */

+    if (cinfo->input_components < 1)

+      ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+    break;

+  }

+

+  /* Check num_components, set conversion method based on requested space */

+  switch (cinfo->jpeg_color_space) {

+  case JCS_GRAYSCALE:

+    if (cinfo->num_components != 1)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    if (cinfo->in_color_space == JCS_GRAYSCALE)

+      cconvert->pub.color_convert = grayscale_convert;

+    else if (cinfo->in_color_space == JCS_RGB) {

+      cconvert->pub.start_pass = rgb_ycc_start;

+      cconvert->pub.color_convert = rgb_gray_convert;

+    } else if (cinfo->in_color_space == JCS_YCbCr)

+      cconvert->pub.color_convert = grayscale_convert;

+    else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_RGB:

+    if (cinfo->num_components != 3)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    if (cinfo->in_color_space == JCS_RGB && RGB_PIXELSIZE == 3)

+      cconvert->pub.color_convert = null_convert;

+    else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_YCbCr:

+    if (cinfo->num_components != 3)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    if (cinfo->in_color_space == JCS_RGB) {

+      cconvert->pub.start_pass = rgb_ycc_start;

+      cconvert->pub.color_convert = rgb_ycc_convert;

+    } else if (cinfo->in_color_space == JCS_YCbCr)

+      cconvert->pub.color_convert = null_convert;

+    else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_CMYK:

+    if (cinfo->num_components != 4)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    if (cinfo->in_color_space == JCS_CMYK)

+      cconvert->pub.color_convert = null_convert;

+    else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_YCCK:

+    if (cinfo->num_components != 4)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    if (cinfo->in_color_space == JCS_CMYK) {

+      cconvert->pub.start_pass = rgb_ycc_start;

+      cconvert->pub.color_convert = cmyk_ycck_convert;

+    } else if (cinfo->in_color_space == JCS_YCCK)

+      cconvert->pub.color_convert = null_convert;

+    else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  default:			/* allow null conversion of JCS_UNKNOWN */

+    if (cinfo->jpeg_color_space != cinfo->in_color_space ||

+	cinfo->num_components != cinfo->input_components)

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    cconvert->pub.color_convert = null_convert;

+    break;

+  }

+}

diff --git a/code/jpeg-6/jcdctmgr.c b/code/jpeg-6/jcdctmgr.c
new file mode 100755
index 0000000..52a72a2
--- /dev/null
+++ b/code/jpeg-6/jcdctmgr.c
@@ -0,0 +1,391 @@
+/*

+ * jcdctmgr.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the forward-DCT management logic.

+ * This code selects a particular DCT implementation to be used,

+ * and it performs related housekeeping chores including coefficient

+ * quantization.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+

+/* Private subobject for this module */

+

+typedef struct {

+  struct jpeg_forward_dct pub;	/* public fields */

+

+  /* Pointer to the DCT routine actually in use */

+  forward_DCT_method_ptr do_dct;

+

+  /* The actual post-DCT divisors --- not identical to the quant table

+   * entries, because of scaling (especially for an unnormalized DCT).

+   * Each table is given in normal array order; note that this must

+   * be converted from the zigzag order of the quantization tables.

+   */

+  DCTELEM * divisors[NUM_QUANT_TBLS];

+

+#ifdef DCT_FLOAT_SUPPORTED

+  /* Same as above for the floating-point case. */

+  float_DCT_method_ptr do_float_dct;

+  FAST_FLOAT * float_divisors[NUM_QUANT_TBLS];

+#endif

+} my_fdct_controller;

+

+typedef my_fdct_controller * my_fdct_ptr;

+

+

+/*

+ * Initialize for a processing pass.

+ * Verify that all referenced Q-tables are present, and set up

+ * the divisor table for each one.

+ * In the current implementation, DCT of all components is done during

+ * the first pass, even if only some components will be output in the

+ * first scan.  Hence all components should be examined here.

+ */

+

+METHODDEF void

+start_pass_fdctmgr (j_compress_ptr cinfo)

+{

+  my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;

+  int ci, qtblno, i;

+  jpeg_component_info *compptr;

+  JQUANT_TBL * qtbl;

+#ifdef DCT_ISLOW_SUPPORTED

+  DCTELEM * dtbl;

+#endif

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    qtblno = compptr->quant_tbl_no;

+    /* Make sure specified quantization table is present */

+    if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||

+	cinfo->quant_tbl_ptrs[qtblno] == NULL)

+      ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);

+    qtbl = cinfo->quant_tbl_ptrs[qtblno];

+    /* Compute divisors for this quant table */

+    /* We may do this more than once for same table, but it's not a big deal */

+    switch (cinfo->dct_method) {

+#ifdef DCT_ISLOW_SUPPORTED

+    case JDCT_ISLOW:

+      /* For LL&M IDCT method, divisors are equal to raw quantization

+       * coefficients multiplied by 8 (to counteract scaling).

+       */

+      if (fdct->divisors[qtblno] == NULL) {

+	fdct->divisors[qtblno] = (DCTELEM *)

+	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				      DCTSIZE2 * SIZEOF(DCTELEM));

+      }

+      dtbl = fdct->divisors[qtblno];

+      for (i = 0; i < DCTSIZE2; i++) {

+	dtbl[i] = ((DCTELEM) qtbl->quantval[jpeg_zigzag_order[i]]) << 3;

+      }

+      break;

+#endif

+#ifdef DCT_IFAST_SUPPORTED

+    case JDCT_IFAST:

+      {

+	/* For AA&N IDCT method, divisors are equal to quantization

+	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

+	 *   scalefactor[0] = 1

+	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

+	 * We apply a further scale factor of 8.

+	 */

+#define CONST_BITS 14

+	static const INT16 aanscales[DCTSIZE2] = {

+	  /* precomputed values scaled up by 14 bits: in natural order */

+	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

+	  22725, 31521, 29692, 26722, 22725, 17855, 12299,  6270,

+	  21407, 29692, 27969, 25172, 21407, 16819, 11585,  5906,

+	  19266, 26722, 25172, 22654, 19266, 15137, 10426,  5315,

+	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

+	  12873, 17855, 16819, 15137, 12873, 10114,  6967,  3552,

+	   8867, 12299, 11585, 10426,  8867,  6967,  4799,  2446,

+	   4520,  6270,  5906,  5315,  4520,  3552,  2446,  1247

+	};

+	SHIFT_TEMPS

+

+	if (fdct->divisors[qtblno] == NULL) {

+	  fdct->divisors[qtblno] = (DCTELEM *)

+	    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+					DCTSIZE2 * SIZEOF(DCTELEM));

+	}

+	dtbl = fdct->divisors[qtblno];

+	for (i = 0; i < DCTSIZE2; i++) {

+	  dtbl[i] = (DCTELEM)

+	    DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[jpeg_zigzag_order[i]],

+				  (INT32) aanscales[i]),

+		    CONST_BITS-3);

+	}

+      }

+      break;

+#endif

+#ifdef DCT_FLOAT_SUPPORTED

+    case JDCT_FLOAT:

+      {

+	/* For float AA&N IDCT method, divisors are equal to quantization

+	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

+	 *   scalefactor[0] = 1

+	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

+	 * We apply a further scale factor of 8.

+	 * What's actually stored is 1/divisor so that the inner loop can

+	 * use a multiplication rather than a division.

+	 */

+	FAST_FLOAT * fdtbl;

+	int row, col;

+	static const double aanscalefactor[DCTSIZE] = {

+	  1.0, 1.387039845, 1.306562965, 1.175875602,

+	  1.0, 0.785694958, 0.541196100, 0.275899379

+	};

+

+	if (fdct->float_divisors[qtblno] == NULL) {

+	  fdct->float_divisors[qtblno] = (FAST_FLOAT *)

+	    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+					DCTSIZE2 * SIZEOF(FAST_FLOAT));

+	}

+	fdtbl = fdct->float_divisors[qtblno];

+	i = 0;

+	for (row = 0; row < DCTSIZE; row++) {

+	  for (col = 0; col < DCTSIZE; col++) {

+	    fdtbl[i] = (FAST_FLOAT)

+	      (1.0 / (((double) qtbl->quantval[jpeg_zigzag_order[i]] *

+		       aanscalefactor[row] * aanscalefactor[col] * 8.0)));

+	    i++;

+	  }

+	}

+      }

+      break;

+#endif

+    default:

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+      break;

+    }

+  }

+}

+

+

+/*

+ * Perform forward DCT on one or more blocks of a component.

+ *

+ * The input samples are taken from the sample_data[] array starting at

+ * position start_row/start_col, and moving to the right for any additional

+ * blocks. The quantized coefficients are returned in coef_blocks[].

+ */

+

+#if 0 // bk001204

+METHODDEF void

+forward_DCT (j_compress_ptr cinfo, jpeg_component_info * compptr,

+	     JSAMPARRAY sample_data, JBLOCKROW coef_blocks,

+	     JDIMENSION start_row, JDIMENSION start_col,

+	     JDIMENSION num_blocks)

+/* This version is used for integer DCT implementations. */

+{

+  /* This routine is heavily used, so it's worth coding it tightly. */

+  my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;

+  forward_DCT_method_ptr do_dct = fdct->do_dct;

+  DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no];

+  DCTELEM workspace[DCTSIZE2];	/* work area for FDCT subroutine */

+  JDIMENSION bi;

+

+  sample_data += start_row;	/* fold in the vertical offset once */

+

+  for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {

+    /* Load data into workspace, applying unsigned->signed conversion */

+    { register DCTELEM *workspaceptr;

+      register JSAMPROW elemptr;

+      register int elemr;

+

+      workspaceptr = workspace;

+      for (elemr = 0; elemr < DCTSIZE; elemr++) {

+	elemptr = sample_data[elemr] + start_col;

+#if DCTSIZE == 8		/* unroll the inner loop */

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+#else

+	{ register int elemc;

+	  for (elemc = DCTSIZE; elemc > 0; elemc--) {

+	    *workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;

+	  }

+	}

+#endif

+      }

+    }

+

+    /* Perform the DCT */

+    (*do_dct) (workspace);

+

+    /* Quantize/descale the coefficients, and store into coef_blocks[] */

+    { register DCTELEM temp, qval;

+      register int i;

+      register JCOEFPTR output_ptr = coef_blocks[bi];

+

+      for (i = 0; i < DCTSIZE2; i++) {

+	qval = divisors[i];

+	temp = workspace[i];

+	/* Divide the coefficient value by qval, ensuring proper rounding.

+	 * Since C does not specify the direction of rounding for negative

+	 * quotients, we have to force the dividend positive for portability.

+	 *

+	 * In most files, at least half of the output values will be zero

+	 * (at default quantization settings, more like three-quarters...)

+	 * so we should ensure that this case is fast.  On many machines,

+	 * a comparison is enough cheaper than a divide to make a special test

+	 * a win.  Since both inputs will be nonnegative, we need only test

+	 * for a < b to discover whether a/b is 0.

+	 * If your machine's division is fast enough, define FAST_DIVIDE.

+	 */

+#ifdef FAST_DIVIDE

+#define DIVIDE_BY(a,b)	a /= b

+#else

+#define DIVIDE_BY(a,b)	if (a >= b) a /= b; else a = 0

+#endif

+	if (temp < 0) {

+	  temp = -temp;

+	  temp += qval>>1;	/* for rounding */

+	  DIVIDE_BY(temp, qval);

+	  temp = -temp;

+	} else {

+	  temp += qval>>1;	/* for rounding */

+	  DIVIDE_BY(temp, qval);

+	}

+	output_ptr[i] = (JCOEF) temp;

+      }

+    }

+  }

+}

+#endif // 0

+

+#ifdef DCT_FLOAT_SUPPORTED

+

+METHODDEF void

+forward_DCT_float (j_compress_ptr cinfo, jpeg_component_info * compptr,

+		   JSAMPARRAY sample_data, JBLOCKROW coef_blocks,

+		   JDIMENSION start_row, JDIMENSION start_col,

+		   JDIMENSION num_blocks)

+/* This version is used for floating-point DCT implementations. */

+{

+  /* This routine is heavily used, so it's worth coding it tightly. */

+  my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;

+  float_DCT_method_ptr do_dct = fdct->do_float_dct;

+  FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no];

+  FAST_FLOAT workspace[DCTSIZE2]; /* work area for FDCT subroutine */

+  JDIMENSION bi;

+

+  sample_data += start_row;	/* fold in the vertical offset once */

+

+  for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {

+    /* Load data into workspace, applying unsigned->signed conversion */

+    { register FAST_FLOAT *workspaceptr;

+      register JSAMPROW elemptr;

+      register int elemr;

+

+      workspaceptr = workspace;

+      for (elemr = 0; elemr < DCTSIZE; elemr++) {

+	elemptr = sample_data[elemr] + start_col;

+#if DCTSIZE == 8		/* unroll the inner loop */

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+#else

+	{ register int elemc;

+	  for (elemc = DCTSIZE; elemc > 0; elemc--) {

+	    *workspaceptr++ = (FAST_FLOAT)

+	      (GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);

+	  }

+	}

+#endif

+      }

+    }

+

+    /* Perform the DCT */

+    (*do_dct) (workspace);

+

+    /* Quantize/descale the coefficients, and store into coef_blocks[] */

+    { register FAST_FLOAT temp;

+      register int i;

+      register JCOEFPTR output_ptr = coef_blocks[bi];

+

+      for (i = 0; i < DCTSIZE2; i++) {

+	/* Apply the quantization and scaling factor */

+	temp = workspace[i] * divisors[i];

+	/* Round to nearest integer.

+	 * Since C does not specify the direction of rounding for negative

+	 * quotients, we have to force the dividend positive for portability.

+	 * The maximum coefficient size is +-16K (for 12-bit data), so this

+	 * code should work for either 16-bit or 32-bit ints.

+	 */

+	output_ptr[i] = (JCOEF) ((int) (temp + (FAST_FLOAT) 16384.5) - 16384);

+      }

+    }

+  }

+}

+

+#endif /* DCT_FLOAT_SUPPORTED */

+

+

+/*

+ * Initialize FDCT manager.

+ */

+

+GLOBAL void

+jinit_forward_dct (j_compress_ptr cinfo)

+{

+  my_fdct_ptr fdct;

+  int i;

+

+  fdct = (my_fdct_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_fdct_controller));

+  cinfo->fdct = (struct jpeg_forward_dct *) fdct;

+  fdct->pub.start_pass = start_pass_fdctmgr;

+

+  switch (cinfo->dct_method) {

+#ifdef DCT_ISLOW_SUPPORTED

+  case JDCT_ISLOW:

+    fdct->pub.forward_DCT = forward_DCT;

+    fdct->do_dct = jpeg_fdct_islow;

+    break;

+#endif

+#ifdef DCT_IFAST_SUPPORTED

+  case JDCT_IFAST:

+    fdct->pub.forward_DCT = forward_DCT;

+    fdct->do_dct = jpeg_fdct_ifast;

+    break;

+#endif

+#ifdef DCT_FLOAT_SUPPORTED

+  case JDCT_FLOAT:

+    fdct->pub.forward_DCT = forward_DCT_float;

+    fdct->do_float_dct = jpeg_fdct_float;

+    break;

+#endif

+  default:

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+    break;

+  }

+

+  /* Mark divisor tables unallocated */

+  for (i = 0; i < NUM_QUANT_TBLS; i++) {

+    fdct->divisors[i] = NULL;

+#ifdef DCT_FLOAT_SUPPORTED

+    fdct->float_divisors[i] = NULL;

+#endif

+  }

+}

diff --git a/code/jpeg-6/jchuff.c b/code/jpeg-6/jchuff.c
new file mode 100755
index 0000000..d6a81ef
--- /dev/null
+++ b/code/jpeg-6/jchuff.c
@@ -0,0 +1,846 @@
+/*

+ * jchuff.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains Huffman entropy encoding routines.

+ *

+ * Much of the complexity here has to do with supporting output suspension.

+ * If the data destination module demands suspension, we want to be able to

+ * back up to the start of the current MCU.  To do this, we copy state

+ * variables into local working storage, and update them back to the

+ * permanent JPEG objects only upon successful completion of an MCU.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jchuff.h"		/* Declarations shared with jcphuff.c */

+

+

+/* Expanded entropy encoder object for Huffman encoding.

+ *

+ * The savable_state subrecord contains fields that change within an MCU,

+ * but must not be updated permanently until we complete the MCU.

+ */

+

+typedef struct {

+  INT32 put_buffer;		/* current bit-accumulation buffer */

+  int put_bits;			/* # of bits now in it */

+  int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */

+} savable_state;

+

+/* This macro is to work around compilers with missing or broken

+ * structure assignment.  You'll need to fix this code if you have

+ * such a compiler and you change MAX_COMPS_IN_SCAN.

+ */

+

+#ifndef NO_STRUCT_ASSIGN

+#define ASSIGN_STATE(dest,src)  ((dest) = (src))

+#else

+#if MAX_COMPS_IN_SCAN == 4

+#define ASSIGN_STATE(dest,src)  \

+	((dest).put_buffer = (src).put_buffer, \

+	 (dest).put_bits = (src).put_bits, \

+	 (dest).last_dc_val[0] = (src).last_dc_val[0], \

+	 (dest).last_dc_val[1] = (src).last_dc_val[1], \

+	 (dest).last_dc_val[2] = (src).last_dc_val[2], \

+	 (dest).last_dc_val[3] = (src).last_dc_val[3])

+#endif

+#endif

+

+

+typedef struct {

+  struct jpeg_entropy_encoder pub; /* public fields */

+

+  savable_state saved;		/* Bit buffer & DC state at start of MCU */

+

+  /* These fields are NOT loaded into local working state. */

+  unsigned int restarts_to_go;	/* MCUs left in this restart interval */

+  int next_restart_num;		/* next restart number to write (0-7) */

+

+  /* Pointers to derived tables (these workspaces have image lifespan) */

+  c_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];

+  c_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];

+

+#ifdef ENTROPY_OPT_SUPPORTED	/* Statistics tables for optimization */

+  long * dc_count_ptrs[NUM_HUFF_TBLS];

+  long * ac_count_ptrs[NUM_HUFF_TBLS];

+#endif

+} huff_entropy_encoder;

+

+typedef huff_entropy_encoder * huff_entropy_ptr;

+

+/* Working state while writing an MCU.

+ * This struct contains all the fields that are needed by subroutines.

+ */

+

+typedef struct {

+  JOCTET * next_output_byte;	/* => next byte to write in buffer */

+  size_t free_in_buffer;	/* # of byte spaces remaining in buffer */

+  savable_state cur;		/* Current bit buffer & DC state */

+  j_compress_ptr cinfo;		/* dump_buffer needs access to this */

+} working_state;

+

+

+/* Forward declarations */

+METHODDEF boolean encode_mcu_huff JPP((j_compress_ptr cinfo,

+				       JBLOCKROW *MCU_data));

+METHODDEF void finish_pass_huff JPP((j_compress_ptr cinfo));

+#ifdef ENTROPY_OPT_SUPPORTED

+METHODDEF boolean encode_mcu_gather JPP((j_compress_ptr cinfo,

+					 JBLOCKROW *MCU_data));

+METHODDEF void finish_pass_gather JPP((j_compress_ptr cinfo));

+#endif

+

+

+/*

+ * Initialize for a Huffman-compressed scan.

+ * If gather_statistics is TRUE, we do not output anything during the scan,

+ * just count the Huffman symbols used and generate Huffman code tables.

+ */

+

+METHODDEF void

+start_pass_huff (j_compress_ptr cinfo, boolean gather_statistics)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  int ci, dctbl, actbl;

+  jpeg_component_info * compptr;

+

+  if (gather_statistics) {

+#ifdef ENTROPY_OPT_SUPPORTED

+    entropy->pub.encode_mcu = encode_mcu_gather;

+    entropy->pub.finish_pass = finish_pass_gather;

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+  } else {

+    entropy->pub.encode_mcu = encode_mcu_huff;

+    entropy->pub.finish_pass = finish_pass_huff;

+  }

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    dctbl = compptr->dc_tbl_no;

+    actbl = compptr->ac_tbl_no;

+    /* Make sure requested tables are present */

+    /* (In gather mode, tables need not be allocated yet) */

+    if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS ||

+	(cinfo->dc_huff_tbl_ptrs[dctbl] == NULL && !gather_statistics))

+      ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);

+    if (actbl < 0 || actbl >= NUM_HUFF_TBLS ||

+	(cinfo->ac_huff_tbl_ptrs[actbl] == NULL && !gather_statistics))

+      ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl);

+    if (gather_statistics) {

+#ifdef ENTROPY_OPT_SUPPORTED

+      /* Allocate and zero the statistics tables */

+      /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */

+      if (entropy->dc_count_ptrs[dctbl] == NULL)

+	entropy->dc_count_ptrs[dctbl] = (long *)

+	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				      257 * SIZEOF(long));

+      MEMZERO(entropy->dc_count_ptrs[dctbl], 257 * SIZEOF(long));

+      if (entropy->ac_count_ptrs[actbl] == NULL)

+	entropy->ac_count_ptrs[actbl] = (long *)

+	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				      257 * SIZEOF(long));

+      MEMZERO(entropy->ac_count_ptrs[actbl], 257 * SIZEOF(long));

+#endif

+    } else {

+      /* Compute derived values for Huffman tables */

+      /* We may do this more than once for a table, but it's not expensive */

+      jpeg_make_c_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[dctbl],

+			      & entropy->dc_derived_tbls[dctbl]);

+      jpeg_make_c_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[actbl],

+			      & entropy->ac_derived_tbls[actbl]);

+    }

+    /* Initialize DC predictions to 0 */

+    entropy->saved.last_dc_val[ci] = 0;

+  }

+

+  /* Initialize bit buffer to empty */

+  entropy->saved.put_buffer = 0;

+  entropy->saved.put_bits = 0;

+

+  /* Initialize restart stuff */

+  entropy->restarts_to_go = cinfo->restart_interval;

+  entropy->next_restart_num = 0;

+}

+

+

+/*

+ * Compute the derived values for a Huffman table.

+ * Note this is also used by jcphuff.c.

+ */

+

+GLOBAL void

+jpeg_make_c_derived_tbl (j_compress_ptr cinfo, JHUFF_TBL * htbl,

+			 c_derived_tbl ** pdtbl)

+{

+  c_derived_tbl *dtbl;

+  int p, i, l, lastp, si;

+  char huffsize[257];

+  unsigned int huffcode[257];

+  unsigned int code;

+

+  /* Allocate a workspace if we haven't already done so. */

+  if (*pdtbl == NULL)

+    *pdtbl = (c_derived_tbl *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(c_derived_tbl));

+  dtbl = *pdtbl;

+  

+  /* Figure C.1: make table of Huffman code length for each symbol */

+  /* Note that this is in code-length order. */

+

+  p = 0;

+  for (l = 1; l <= 16; l++) {

+    for (i = 1; i <= (int) htbl->bits[l]; i++)

+      huffsize[p++] = (char) l;

+  }

+  huffsize[p] = 0;

+  lastp = p;

+  

+  /* Figure C.2: generate the codes themselves */

+  /* Note that this is in code-length order. */

+  

+  code = 0;

+  si = huffsize[0];

+  p = 0;

+  while (huffsize[p]) {

+    while (((int) huffsize[p]) == si) {

+      huffcode[p++] = code;

+      code++;

+    }

+    code <<= 1;

+    si++;

+  }

+  

+  /* Figure C.3: generate encoding tables */

+  /* These are code and size indexed by symbol value */

+

+  /* Set any codeless symbols to have code length 0;

+   * this allows emit_bits to detect any attempt to emit such symbols.

+   */

+  MEMZERO(dtbl->ehufsi, SIZEOF(dtbl->ehufsi));

+

+  for (p = 0; p < lastp; p++) {

+    dtbl->ehufco[htbl->huffval[p]] = huffcode[p];

+    dtbl->ehufsi[htbl->huffval[p]] = huffsize[p];

+  }

+}

+

+

+/* Outputting bytes to the file */

+

+/* Emit a byte, taking 'action' if must suspend. */

+#define emit_byte(state,val,action)  \

+	{ *(state)->next_output_byte++ = (JOCTET) (val);  \

+	  if (--(state)->free_in_buffer == 0)  \

+	    if (! dump_buffer(state))  \

+	      { action; } }

+

+

+LOCAL boolean

+dump_buffer (working_state * state)

+/* Empty the output buffer; return TRUE if successful, FALSE if must suspend */

+{

+  struct jpeg_destination_mgr * dest = state->cinfo->dest;

+

+  if (! (*dest->empty_output_buffer) (state->cinfo))

+    return FALSE;

+  /* After a successful buffer dump, must reset buffer pointers */

+  state->next_output_byte = dest->next_output_byte;

+  state->free_in_buffer = dest->free_in_buffer;

+  return TRUE;

+}

+

+

+/* Outputting bits to the file */

+

+/* Only the right 24 bits of put_buffer are used; the valid bits are

+ * left-justified in this part.  At most 16 bits can be passed to emit_bits

+ * in one call, and we never retain more than 7 bits in put_buffer

+ * between calls, so 24 bits are sufficient.

+ */

+

+INLINE

+LOCAL boolean

+emit_bits (working_state * state, unsigned int code, int size)

+/* Emit some bits; return TRUE if successful, FALSE if must suspend */

+{

+  /* This routine is heavily used, so it's worth coding tightly. */

+  register INT32 put_buffer = (INT32) code;

+  register int put_bits = state->cur.put_bits;

+

+  /* if size is 0, caller used an invalid Huffman table entry */

+  if (size == 0)

+    ERREXIT(state->cinfo, JERR_HUFF_MISSING_CODE);

+

+  put_buffer &= (((INT32) 1)<<size) - 1; /* mask off any extra bits in code */

+  

+  put_bits += size;		/* new number of bits in buffer */

+  

+  put_buffer <<= 24 - put_bits; /* align incoming bits */

+

+  put_buffer |= state->cur.put_buffer; /* and merge with old buffer contents */

+  

+  while (put_bits >= 8) {

+    int c = (int) ((put_buffer >> 16) & 0xFF);

+    

+    emit_byte(state, c, return FALSE);

+    if (c == 0xFF) {		/* need to stuff a zero byte? */

+      emit_byte(state, 0, return FALSE);

+    }

+    put_buffer <<= 8;

+    put_bits -= 8;

+  }

+

+  state->cur.put_buffer = put_buffer; /* update state variables */

+  state->cur.put_bits = put_bits;

+

+  return TRUE;

+}

+

+

+LOCAL boolean

+flush_bits (working_state * state)

+{

+  if (! emit_bits(state, 0x7F, 7)) /* fill any partial byte with ones */

+    return FALSE;

+  state->cur.put_buffer = 0;	/* and reset bit-buffer to empty */

+  state->cur.put_bits = 0;

+  return TRUE;

+}

+

+

+/* Encode a single block's worth of coefficients */

+

+LOCAL boolean

+encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,

+		  c_derived_tbl *dctbl, c_derived_tbl *actbl)

+{

+  register int temp, temp2;

+  register int nbits;

+  register int k, r, i;

+  

+  /* Encode the DC coefficient difference per section F.1.2.1 */

+  

+  temp = temp2 = block[0] - last_dc_val;

+

+  if (temp < 0) {

+    temp = -temp;		/* temp is abs value of input */

+    /* For a negative input, want temp2 = bitwise complement of abs(input) */

+    /* This code assumes we are on a two's complement machine */

+    temp2--;

+  }

+  

+  /* Find the number of bits needed for the magnitude of the coefficient */

+  nbits = 0;

+  while (temp) {

+    nbits++;

+    temp >>= 1;

+  }

+  

+  /* Emit the Huffman-coded symbol for the number of bits */

+  if (! emit_bits(state, dctbl->ehufco[nbits], dctbl->ehufsi[nbits]))

+    return FALSE;

+

+  /* Emit that number of bits of the value, if positive, */

+  /* or the complement of its magnitude, if negative. */

+  if (nbits)			/* emit_bits rejects calls with size 0 */

+    if (! emit_bits(state, (unsigned int) temp2, nbits))

+      return FALSE;

+

+  /* Encode the AC coefficients per section F.1.2.2 */

+  

+  r = 0;			/* r = run length of zeros */

+  

+  for (k = 1; k < DCTSIZE2; k++) {

+    if ((temp = block[jpeg_natural_order[k]]) == 0) {

+      r++;

+    } else {

+      /* if run length > 15, must emit special run-length-16 codes (0xF0) */

+      while (r > 15) {

+	if (! emit_bits(state, actbl->ehufco[0xF0], actbl->ehufsi[0xF0]))

+	  return FALSE;

+	r -= 16;

+      }

+

+      temp2 = temp;

+      if (temp < 0) {

+	temp = -temp;		/* temp is abs value of input */

+	/* This code assumes we are on a two's complement machine */

+	temp2--;

+      }

+      

+      /* Find the number of bits needed for the magnitude of the coefficient */

+      nbits = 1;		/* there must be at least one 1 bit */

+      while ((temp >>= 1))

+	nbits++;

+      

+      /* Emit Huffman symbol for run length / number of bits */

+      i = (r << 4) + nbits;

+      if (! emit_bits(state, actbl->ehufco[i], actbl->ehufsi[i]))

+	return FALSE;

+

+      /* Emit that number of bits of the value, if positive, */

+      /* or the complement of its magnitude, if negative. */

+      if (! emit_bits(state, (unsigned int) temp2, nbits))

+	return FALSE;

+      

+      r = 0;

+    }

+  }

+

+  /* If the last coef(s) were zero, emit an end-of-block code */

+  if (r > 0)

+    if (! emit_bits(state, actbl->ehufco[0], actbl->ehufsi[0]))

+      return FALSE;

+

+  return TRUE;

+}

+

+

+/*

+ * Emit a restart marker & resynchronize predictions.

+ */

+

+LOCAL boolean

+emit_restart (working_state * state, int restart_num)

+{

+  int ci;

+

+  if (! flush_bits(state))

+    return FALSE;

+

+  emit_byte(state, 0xFF, return FALSE);

+  emit_byte(state, JPEG_RST0 + restart_num, return FALSE);

+

+  /* Re-initialize DC predictions to 0 */

+  for (ci = 0; ci < state->cinfo->comps_in_scan; ci++)

+    state->cur.last_dc_val[ci] = 0;

+

+  /* The restart counter is not updated until we successfully write the MCU. */

+

+  return TRUE;

+}

+

+

+/*

+ * Encode and output one MCU's worth of Huffman-compressed coefficients.

+ */

+

+METHODDEF boolean

+encode_mcu_huff (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  working_state state;

+  int blkn, ci;

+  jpeg_component_info * compptr;

+

+  /* Load up working state */

+  state.next_output_byte = cinfo->dest->next_output_byte;

+  state.free_in_buffer = cinfo->dest->free_in_buffer;

+  ASSIGN_STATE(state.cur, entropy->saved);

+  state.cinfo = cinfo;

+

+  /* Emit restart marker if needed */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! emit_restart(&state, entropy->next_restart_num))

+	return FALSE;

+  }

+

+  /* Encode the MCU data blocks */

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    ci = cinfo->MCU_membership[blkn];

+    compptr = cinfo->cur_comp_info[ci];

+    if (! encode_one_block(&state,

+			   MCU_data[blkn][0], state.cur.last_dc_val[ci],

+			   entropy->dc_derived_tbls[compptr->dc_tbl_no],

+			   entropy->ac_derived_tbls[compptr->ac_tbl_no]))

+      return FALSE;

+    /* Update last_dc_val */

+    state.cur.last_dc_val[ci] = MCU_data[blkn][0][0];

+  }

+

+  /* Completed MCU, so update state */

+  cinfo->dest->next_output_byte = state.next_output_byte;

+  cinfo->dest->free_in_buffer = state.free_in_buffer;

+  ASSIGN_STATE(entropy->saved, state.cur);

+

+  /* Update restart-interval state too */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      entropy->restarts_to_go = cinfo->restart_interval;

+      entropy->next_restart_num++;

+      entropy->next_restart_num &= 7;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * Finish up at the end of a Huffman-compressed scan.

+ */

+

+METHODDEF void

+finish_pass_huff (j_compress_ptr cinfo)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  working_state state;

+

+  /* Load up working state ... flush_bits needs it */

+  state.next_output_byte = cinfo->dest->next_output_byte;

+  state.free_in_buffer = cinfo->dest->free_in_buffer;

+  ASSIGN_STATE(state.cur, entropy->saved);

+  state.cinfo = cinfo;

+

+  /* Flush out the last data */

+  if (! flush_bits(&state))

+    ERREXIT(cinfo, JERR_CANT_SUSPEND);

+

+  /* Update state */

+  cinfo->dest->next_output_byte = state.next_output_byte;

+  cinfo->dest->free_in_buffer = state.free_in_buffer;

+  ASSIGN_STATE(entropy->saved, state.cur);

+}

+

+

+/*

+ * Huffman coding optimization.

+ *

+ * This actually is optimization, in the sense that we find the best possible

+ * Huffman table(s) for the given data.  We first scan the supplied data and

+ * count the number of uses of each symbol that is to be Huffman-coded.

+ * (This process must agree with the code above.)  Then we build an

+ * optimal Huffman coding tree for the observed counts.

+ *

+ * The JPEG standard requires Huffman codes to be no more than 16 bits long.

+ * If some symbols have a very small but nonzero probability, the Huffman tree

+ * must be adjusted to meet the code length restriction.  We currently use

+ * the adjustment method suggested in the JPEG spec.  This method is *not*

+ * optimal; it may not choose the best possible limited-length code.  But

+ * since the symbols involved are infrequently used, it's not clear that

+ * going to extra trouble is worthwhile.

+ */

+

+#ifdef ENTROPY_OPT_SUPPORTED

+

+

+/* Process a single block's worth of coefficients */

+

+LOCAL void

+htest_one_block (JCOEFPTR block, int last_dc_val,

+		 long dc_counts[], long ac_counts[])

+{

+  register int temp;

+  register int nbits;

+  register int k, r;

+  

+  /* Encode the DC coefficient difference per section F.1.2.1 */

+  

+  temp = block[0] - last_dc_val;

+  if (temp < 0)

+    temp = -temp;

+  

+  /* Find the number of bits needed for the magnitude of the coefficient */

+  nbits = 0;

+  while (temp) {

+    nbits++;

+    temp >>= 1;

+  }

+

+  /* Count the Huffman symbol for the number of bits */

+  dc_counts[nbits]++;

+  

+  /* Encode the AC coefficients per section F.1.2.2 */

+  

+  r = 0;			/* r = run length of zeros */

+  

+  for (k = 1; k < DCTSIZE2; k++) {

+    if ((temp = block[jpeg_natural_order[k]]) == 0) {

+      r++;

+    } else {

+      /* if run length > 15, must emit special run-length-16 codes (0xF0) */

+      while (r > 15) {

+	ac_counts[0xF0]++;

+	r -= 16;

+      }

+      

+      /* Find the number of bits needed for the magnitude of the coefficient */

+      if (temp < 0)

+	temp = -temp;

+      

+      /* Find the number of bits needed for the magnitude of the coefficient */

+      nbits = 1;		/* there must be at least one 1 bit */

+      while ((temp >>= 1))

+	nbits++;

+      

+      /* Count Huffman symbol for run length / number of bits */

+      ac_counts[(r << 4) + nbits]++;

+      

+      r = 0;

+    }

+  }

+

+  /* If the last coef(s) were zero, emit an end-of-block code */

+  if (r > 0)

+    ac_counts[0]++;

+}

+

+

+/*

+ * Trial-encode one MCU's worth of Huffman-compressed coefficients.

+ * No data is actually output, so no suspension return is possible.

+ */

+

+METHODDEF boolean

+encode_mcu_gather (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  int blkn, ci;

+  jpeg_component_info * compptr;

+

+  /* Take care of restart intervals if needed */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      /* Re-initialize DC predictions to 0 */

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++)

+	entropy->saved.last_dc_val[ci] = 0;

+      /* Update restart state */

+      entropy->restarts_to_go = cinfo->restart_interval;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    ci = cinfo->MCU_membership[blkn];

+    compptr = cinfo->cur_comp_info[ci];

+    htest_one_block(MCU_data[blkn][0], entropy->saved.last_dc_val[ci],

+		    entropy->dc_count_ptrs[compptr->dc_tbl_no],

+		    entropy->ac_count_ptrs[compptr->ac_tbl_no]);

+    entropy->saved.last_dc_val[ci] = MCU_data[blkn][0][0];

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * Generate the optimal coding for the given counts, fill htbl.

+ * Note this is also used by jcphuff.c.

+ */

+

+GLOBAL void

+jpeg_gen_optimal_table (j_compress_ptr cinfo, JHUFF_TBL * htbl, long freq[])

+{

+#define MAX_CLEN 32		/* assumed maximum initial code length */

+  UINT8 bits[MAX_CLEN+1];	/* bits[k] = # of symbols with code length k */

+  int codesize[257];		/* codesize[k] = code length of symbol k */

+  int others[257];		/* next symbol in current branch of tree */

+  int c1, c2;

+  int p, i, j;

+  long v;

+

+  /* This algorithm is explained in section K.2 of the JPEG standard */

+

+  MEMZERO(bits, SIZEOF(bits));

+  MEMZERO(codesize, SIZEOF(codesize));

+  for (i = 0; i < 257; i++)

+    others[i] = -1;		/* init links to empty */

+  

+  freq[256] = 1;		/* make sure there is a nonzero count */

+  /* Including the pseudo-symbol 256 in the Huffman procedure guarantees

+   * that no real symbol is given code-value of all ones, because 256

+   * will be placed in the largest codeword category.

+   */

+

+  /* Huffman's basic algorithm to assign optimal code lengths to symbols */

+

+  for (;;) {

+    /* Find the smallest nonzero frequency, set c1 = its symbol */

+    /* In case of ties, take the larger symbol number */

+    c1 = -1;

+    v = 1000000000L;

+    for (i = 0; i <= 256; i++) {

+      if (freq[i] && freq[i] <= v) {

+	v = freq[i];

+	c1 = i;

+      }

+    }

+

+    /* Find the next smallest nonzero frequency, set c2 = its symbol */

+    /* In case of ties, take the larger symbol number */

+    c2 = -1;

+    v = 1000000000L;

+    for (i = 0; i <= 256; i++) {

+      if (freq[i] && freq[i] <= v && i != c1) {

+	v = freq[i];

+	c2 = i;

+      }

+    }

+

+    /* Done if we've merged everything into one frequency */

+    if (c2 < 0)

+      break;

+    

+    /* Else merge the two counts/trees */

+    freq[c1] += freq[c2];

+    freq[c2] = 0;

+

+    /* Increment the codesize of everything in c1's tree branch */

+    codesize[c1]++;

+    while (others[c1] >= 0) {

+      c1 = others[c1];

+      codesize[c1]++;

+    }

+    

+    others[c1] = c2;		/* chain c2 onto c1's tree branch */

+    

+    /* Increment the codesize of everything in c2's tree branch */

+    codesize[c2]++;

+    while (others[c2] >= 0) {

+      c2 = others[c2];

+      codesize[c2]++;

+    }

+  }

+

+  /* Now count the number of symbols of each code length */

+  for (i = 0; i <= 256; i++) {

+    if (codesize[i]) {

+      /* The JPEG standard seems to think that this can't happen, */

+      /* but I'm paranoid... */

+      if (codesize[i] > MAX_CLEN)

+	ERREXIT(cinfo, JERR_HUFF_CLEN_OVERFLOW);

+

+      bits[codesize[i]]++;

+    }

+  }

+

+  /* JPEG doesn't allow symbols with code lengths over 16 bits, so if the pure

+   * Huffman procedure assigned any such lengths, we must adjust the coding.

+   * Here is what the JPEG spec says about how this next bit works:

+   * Since symbols are paired for the longest Huffman code, the symbols are

+   * removed from this length category two at a time.  The prefix for the pair

+   * (which is one bit shorter) is allocated to one of the pair; then,

+   * skipping the BITS entry for that prefix length, a code word from the next

+   * shortest nonzero BITS entry is converted into a prefix for two code words

+   * one bit longer.

+   */

+  

+  for (i = MAX_CLEN; i > 16; i--) {

+    while (bits[i] > 0) {

+      j = i - 2;		/* find length of new prefix to be used */

+      while (bits[j] == 0)

+	j--;

+      

+      bits[i] -= 2;		/* remove two symbols */

+      bits[i-1]++;		/* one goes in this length */

+      bits[j+1] += 2;		/* two new symbols in this length */

+      bits[j]--;		/* symbol of this length is now a prefix */

+    }

+  }

+

+  /* Remove the count for the pseudo-symbol 256 from the largest codelength */

+  while (bits[i] == 0)		/* find largest codelength still in use */

+    i--;

+  bits[i]--;

+  

+  /* Return final symbol counts (only for lengths 0..16) */

+  MEMCOPY(htbl->bits, bits, SIZEOF(htbl->bits));

+  

+  /* Return a list of the symbols sorted by code length */

+  /* It's not real clear to me why we don't need to consider the codelength

+   * changes made above, but the JPEG spec seems to think this works.

+   */

+  p = 0;

+  for (i = 1; i <= MAX_CLEN; i++) {

+    for (j = 0; j <= 255; j++) {

+      if (codesize[j] == i) {

+	htbl->huffval[p] = (UINT8) j;

+	p++;

+      }

+    }

+  }

+

+  /* Set sent_table FALSE so updated table will be written to JPEG file. */

+  htbl->sent_table = FALSE;

+}

+

+

+/*

+ * Finish up a statistics-gathering pass and create the new Huffman tables.

+ */

+

+METHODDEF void

+finish_pass_gather (j_compress_ptr cinfo)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  int ci, dctbl, actbl;

+  jpeg_component_info * compptr;

+  JHUFF_TBL **htblptr;

+  boolean did_dc[NUM_HUFF_TBLS];

+  boolean did_ac[NUM_HUFF_TBLS];

+

+  /* It's important not to apply jpeg_gen_optimal_table more than once

+   * per table, because it clobbers the input frequency counts!

+   */

+  MEMZERO(did_dc, SIZEOF(did_dc));

+  MEMZERO(did_ac, SIZEOF(did_ac));

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    dctbl = compptr->dc_tbl_no;

+    actbl = compptr->ac_tbl_no;

+    if (! did_dc[dctbl]) {

+      htblptr = & cinfo->dc_huff_tbl_ptrs[dctbl];

+      if (*htblptr == NULL)

+	*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);

+      jpeg_gen_optimal_table(cinfo, *htblptr, entropy->dc_count_ptrs[dctbl]);

+      did_dc[dctbl] = TRUE;

+    }

+    if (! did_ac[actbl]) {

+      htblptr = & cinfo->ac_huff_tbl_ptrs[actbl];

+      if (*htblptr == NULL)

+	*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);

+      jpeg_gen_optimal_table(cinfo, *htblptr, entropy->ac_count_ptrs[actbl]);

+      did_ac[actbl] = TRUE;

+    }

+  }

+}

+

+

+#endif /* ENTROPY_OPT_SUPPORTED */

+

+

+/*

+ * Module initialization routine for Huffman entropy encoding.

+ */

+

+GLOBAL void

+jinit_huff_encoder (j_compress_ptr cinfo)

+{

+  huff_entropy_ptr entropy;

+  int i;

+

+  entropy = (huff_entropy_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(huff_entropy_encoder));

+  cinfo->entropy = (struct jpeg_entropy_encoder *) entropy;

+  entropy->pub.start_pass = start_pass_huff;

+

+  /* Mark tables unallocated */

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;

+#ifdef ENTROPY_OPT_SUPPORTED

+    entropy->dc_count_ptrs[i] = entropy->ac_count_ptrs[i] = NULL;

+#endif

+  }

+}

diff --git a/code/jpeg-6/jchuff.h b/code/jpeg-6/jchuff.h
new file mode 100755
index 0000000..0a81d54
--- /dev/null
+++ b/code/jpeg-6/jchuff.h
@@ -0,0 +1,34 @@
+/*

+ * jchuff.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains declarations for Huffman entropy encoding routines

+ * that are shared between the sequential encoder (jchuff.c) and the

+ * progressive encoder (jcphuff.c).  No other modules need to see these.

+ */

+

+/* Derived data constructed for each Huffman table */

+

+typedef struct {

+  unsigned int ehufco[256];	/* code for each symbol */

+  char ehufsi[256];		/* length of code for each symbol */

+  /* If no code has been allocated for a symbol S, ehufsi[S] contains 0 */

+} c_derived_tbl;

+

+/* Short forms of external names for systems with brain-damaged linkers. */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_make_c_derived_tbl	jMkCDerived

+#define jpeg_gen_optimal_table	jGenOptTbl

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+/* Expand a Huffman table definition into the derived format */

+EXTERN void jpeg_make_c_derived_tbl JPP((j_compress_ptr cinfo,

+				JHUFF_TBL * htbl, c_derived_tbl ** pdtbl));

+

+/* Generate an optimal table definition given the specified counts */

+EXTERN void jpeg_gen_optimal_table JPP((j_compress_ptr cinfo,

+					JHUFF_TBL * htbl, long freq[]));

diff --git a/code/jpeg-6/jcinit.c b/code/jpeg-6/jcinit.c
new file mode 100755
index 0000000..8055661
--- /dev/null
+++ b/code/jpeg-6/jcinit.c
@@ -0,0 +1,72 @@
+/*

+ * jcinit.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains initialization logic for the JPEG compressor.

+ * This routine is in charge of selecting the modules to be executed and

+ * making an initialization call to each one.

+ *

+ * Logically, this code belongs in jcmaster.c.  It's split out because

+ * linking this routine implies linking the entire compression library.

+ * For a transcoding-only application, we want to be able to use jcmaster.c

+ * without linking in the whole library.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Master selection of compression modules.

+ * This is done once at the start of processing an image.  We determine

+ * which modules will be used and give them appropriate initialization calls.

+ */

+

+GLOBAL void

+jinit_compress_master (j_compress_ptr cinfo)

+{

+  /* Initialize master control (includes parameter checking/processing) */

+  jinit_c_master_control(cinfo, FALSE /* full compression */);

+

+  /* Preprocessing */

+  if (! cinfo->raw_data_in) {

+    jinit_color_converter(cinfo);

+    jinit_downsampler(cinfo);

+    jinit_c_prep_controller(cinfo, FALSE /* never need full buffer here */);

+  }

+  /* Forward DCT */

+  jinit_forward_dct(cinfo);

+  /* Entropy encoding: either Huffman or arithmetic coding. */

+  if (cinfo->arith_code) {

+    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);

+  } else {

+    if (cinfo->progressive_mode) {

+#ifdef C_PROGRESSIVE_SUPPORTED

+      jinit_phuff_encoder(cinfo);

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    } else

+      jinit_huff_encoder(cinfo);

+  }

+

+  /* Need a full-image coefficient buffer in any multi-pass mode. */

+  jinit_c_coef_controller(cinfo,

+			  (cinfo->num_scans > 1 || cinfo->optimize_coding));

+  jinit_c_main_controller(cinfo, FALSE /* never need full buffer here */);

+

+  jinit_marker_writer(cinfo);

+

+  /* We can now tell the memory manager to allocate virtual arrays. */

+  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);

+

+  /* Write the datastream header (SOI) immediately.

+   * Frame and scan headers are postponed till later.

+   * This lets application insert special markers after the SOI.

+   */

+  (*cinfo->marker->write_file_header) (cinfo);

+}

diff --git a/code/jpeg-6/jcmainct.c b/code/jpeg-6/jcmainct.c
new file mode 100755
index 0000000..3a71c1f
--- /dev/null
+++ b/code/jpeg-6/jcmainct.c
@@ -0,0 +1,296 @@
+/*

+ * jcmainct.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the main buffer controller for compression.

+ * The main buffer lies between the pre-processor and the JPEG

+ * compressor proper; it holds downsampled data in the JPEG colorspace.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Note: currently, there is no operating mode in which a full-image buffer

+ * is needed at this step.  If there were, that mode could not be used with

+ * "raw data" input, since this module is bypassed in that case.  However,

+ * we've left the code here for possible use in special applications.

+ */

+#undef FULL_MAIN_BUFFER_SUPPORTED

+

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_c_main_controller pub; /* public fields */

+

+  JDIMENSION cur_iMCU_row;	/* number of current iMCU row */

+  JDIMENSION rowgroup_ctr;	/* counts row groups received in iMCU row */

+  boolean suspended;		/* remember if we suspended output */

+  J_BUF_MODE pass_mode;		/* current operating mode */

+

+  /* If using just a strip buffer, this points to the entire set of buffers

+   * (we allocate one for each component).  In the full-image case, this

+   * points to the currently accessible strips of the virtual arrays.

+   */

+  JSAMPARRAY buffer[MAX_COMPONENTS];

+

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+  /* If using full-image storage, this array holds pointers to virtual-array

+   * control blocks for each component.  Unused if not full-image storage.

+   */

+  jvirt_sarray_ptr whole_image[MAX_COMPONENTS];

+#endif

+} my_main_controller;

+

+typedef my_main_controller * my_main_ptr;

+

+

+/* Forward declarations */

+METHODDEF void process_data_simple_main

+	JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,

+	     JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+METHODDEF void process_data_buffer_main

+	JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,

+	     JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));

+#endif

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  // bk001204 - don't use main...

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+

+  /* Do nothing in raw-data mode. */

+  if (cinfo->raw_data_in)

+    return;

+

+  jmain->cur_iMCU_row = 0;	/* initialize counters */

+  jmain->rowgroup_ctr = 0;

+  jmain->suspended = FALSE;

+  jmain->pass_mode = pass_mode;	/* save mode for use by process_data */

+

+  switch (pass_mode) {

+  case JBUF_PASS_THRU:

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+    if (jmain->whole_image[0] != NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+#endif

+    jmain->pub.process_data = process_data_simple_main;

+    break;

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+  case JBUF_SAVE_SOURCE:

+  case JBUF_CRANK_DEST:

+  case JBUF_SAVE_AND_PASS:

+    if (jmain->whole_image[0] == NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    jmain->pub.process_data = process_data_buffer_main;

+    break;

+#endif

+  default:

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    break;

+  }

+}

+

+

+/*

+ * Process some data.

+ * This routine handles the simple pass-through mode,

+ * where we have only a strip buffer.

+ */

+

+METHODDEF void

+process_data_simple_main (j_compress_ptr cinfo,

+			  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,

+			  JDIMENSION in_rows_avail)

+{

+  // bk001204 - don't use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+

+  while (jmain->cur_iMCU_row < cinfo->total_iMCU_rows) {

+    /* Read input data if we haven't filled the main buffer yet */

+    if (jmain->rowgroup_ctr < DCTSIZE)

+      (*cinfo->prep->pre_process_data) (cinfo,

+					input_buf, in_row_ctr, in_rows_avail,

+					jmain->buffer, &jmain->rowgroup_ctr,

+					(JDIMENSION) DCTSIZE);

+

+    /* If we don't have a full iMCU row buffered, return to application for

+     * more data.  Note that preprocessor will always pad to fill the iMCU row

+     * at the bottom of the image.

+     */

+    if (jmain->rowgroup_ctr != DCTSIZE)

+      return;

+

+    /* Send the completed row to the compressor */

+    if (! (*cinfo->coef->compress_data) (cinfo, jmain->buffer)) {

+      /* If compressor did not consume the whole row, then we must need to

+       * suspend processing and return to the application.  In this situation

+       * we pretend we didn't yet consume the last input row; otherwise, if

+       * it happened to be the last row of the image, the application would

+       * think we were done.

+       */

+      if (! jmain->suspended) {

+	(*in_row_ctr)--;

+	jmain->suspended = TRUE;

+      }

+      return;

+    }

+    /* We did finish the row.  Undo our little suspension hack if a previous

+     * call suspended; then mark the main buffer empty.

+     */

+    if (jmain->suspended) {

+      (*in_row_ctr)++;

+      jmain->suspended = FALSE;

+    }

+    jmain->rowgroup_ctr = 0;

+    jmain->cur_iMCU_row++;

+  }

+}

+

+

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+

+/*

+ * Process some data.

+ * This routine handles all of the modes that use a full-size buffer.

+ */

+

+METHODDEF void

+process_data_buffer_main (j_compress_ptr cinfo,

+			  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,

+			  JDIMENSION in_rows_avail)

+{

+  my_main_ptr main = (my_main_ptr) cinfo->main;

+  int ci;

+  jpeg_component_info *compptr;

+  boolean writing = (main->pass_mode != JBUF_CRANK_DEST);

+

+  while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {

+    /* Realign the virtual buffers if at the start of an iMCU row. */

+    if (main->rowgroup_ctr == 0) {

+      for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	   ci++, compptr++) {

+	main->buffer[ci] = (*cinfo->mem->access_virt_sarray)

+	  ((j_common_ptr) cinfo, main->whole_image[ci],

+	   main->cur_iMCU_row * (compptr->v_samp_factor * DCTSIZE),

+	   (JDIMENSION) (compptr->v_samp_factor * DCTSIZE), writing);

+      }

+      /* In a read pass, pretend we just read some source data. */

+      if (! writing) {

+	*in_row_ctr += cinfo->max_v_samp_factor * DCTSIZE;

+	main->rowgroup_ctr = DCTSIZE;

+      }

+    }

+

+    /* If a write pass, read input data until the current iMCU row is full. */

+    /* Note: preprocessor will pad if necessary to fill the last iMCU row. */

+    if (writing) {

+      (*cinfo->prep->pre_process_data) (cinfo,

+					input_buf, in_row_ctr, in_rows_avail,

+					main->buffer, &main->rowgroup_ctr,

+					(JDIMENSION) DCTSIZE);

+      /* Return to application if we need more data to fill the iMCU row. */

+      if (main->rowgroup_ctr < DCTSIZE)

+	return;

+    }

+

+    /* Emit data, unless this is a sink-only pass. */

+    if (main->pass_mode != JBUF_SAVE_SOURCE) {

+      if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {

+	/* If compressor did not consume the whole row, then we must need to

+	 * suspend processing and return to the application.  In this situation

+	 * we pretend we didn't yet consume the last input row; otherwise, if

+	 * it happened to be the last row of the image, the application would

+	 * think we were done.

+	 */

+	if (! main->suspended) {

+	  (*in_row_ctr)--;

+	  main->suspended = TRUE;

+	}

+	return;

+      }

+      /* We did finish the row.  Undo our little suspension hack if a previous

+       * call suspended; then mark the main buffer empty.

+       */

+      if (main->suspended) {

+	(*in_row_ctr)++;

+	main->suspended = FALSE;

+      }

+    }

+

+    /* If get here, we are done with this iMCU row.  Mark buffer empty. */

+    main->rowgroup_ctr = 0;

+    main->cur_iMCU_row++;

+  }

+}

+

+#endif /* FULL_MAIN_BUFFER_SUPPORTED */

+

+

+/*

+ * Initialize main buffer controller.

+ */

+

+GLOBAL void

+jinit_c_main_controller (j_compress_ptr cinfo, boolean need_full_buffer)

+{

+  // bk001204 - don't use main

+  my_main_ptr jmain;

+  int ci;

+  jpeg_component_info *compptr;

+

+  jmain = (my_main_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_main_controller));

+  cinfo->main = (struct jpeg_c_main_controller *) jmain;

+  jmain->pub.start_pass = start_pass_main;

+

+  /* We don't need to create a buffer in raw-data mode. */

+  if (cinfo->raw_data_in)

+    return;

+

+  /* Create the buffer.  It holds downsampled data, so each component

+   * may be of a different size.

+   */

+  if (need_full_buffer) {

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+    /* Allocate a full-image virtual array for each component */

+    /* Note we pad the bottom to a multiple of the iMCU height */

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      jmain->whole_image[ci] = (*cinfo->mem->request_virt_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,

+	 compptr->width_in_blocks * DCTSIZE,

+	 (JDIMENSION) jround_up((long) compptr->height_in_blocks,

+				(long) compptr->v_samp_factor) * DCTSIZE,

+	 (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));

+    }

+#else

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+#endif

+  } else {

+#ifdef FULL_MAIN_BUFFER_SUPPORTED

+    jmain->whole_image[0] = NULL; /* flag for no virtual arrays */

+#endif

+    /* Allocate a strip buffer for each component */

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      jmain->buffer[ci] = (*cinfo->mem->alloc_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE,

+	 compptr->width_in_blocks * DCTSIZE,

+	 (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));

+    }

+  }

+}

diff --git a/code/jpeg-6/jcmarker.c b/code/jpeg-6/jcmarker.c
new file mode 100755
index 0000000..4220280
--- /dev/null
+++ b/code/jpeg-6/jcmarker.c
@@ -0,0 +1,639 @@
+/*

+ * jcmarker.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains routines to write JPEG datastream markers.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+typedef enum {			/* JPEG marker codes */

+  M_SOF0  = 0xc0,

+  M_SOF1  = 0xc1,

+  M_SOF2  = 0xc2,

+  M_SOF3  = 0xc3,

+  

+  M_SOF5  = 0xc5,

+  M_SOF6  = 0xc6,

+  M_SOF7  = 0xc7,

+  

+  M_JPG   = 0xc8,

+  M_SOF9  = 0xc9,

+  M_SOF10 = 0xca,

+  M_SOF11 = 0xcb,

+  

+  M_SOF13 = 0xcd,

+  M_SOF14 = 0xce,

+  M_SOF15 = 0xcf,

+  

+  M_DHT   = 0xc4,

+  

+  M_DAC   = 0xcc,

+  

+  M_RST0  = 0xd0,

+  M_RST1  = 0xd1,

+  M_RST2  = 0xd2,

+  M_RST3  = 0xd3,

+  M_RST4  = 0xd4,

+  M_RST5  = 0xd5,

+  M_RST6  = 0xd6,

+  M_RST7  = 0xd7,

+  

+  M_SOI   = 0xd8,

+  M_EOI   = 0xd9,

+  M_SOS   = 0xda,

+  M_DQT   = 0xdb,

+  M_DNL   = 0xdc,

+  M_DRI   = 0xdd,

+  M_DHP   = 0xde,

+  M_EXP   = 0xdf,

+  

+  M_APP0  = 0xe0,

+  M_APP1  = 0xe1,

+  M_APP2  = 0xe2,

+  M_APP3  = 0xe3,

+  M_APP4  = 0xe4,

+  M_APP5  = 0xe5,

+  M_APP6  = 0xe6,

+  M_APP7  = 0xe7,

+  M_APP8  = 0xe8,

+  M_APP9  = 0xe9,

+  M_APP10 = 0xea,

+  M_APP11 = 0xeb,

+  M_APP12 = 0xec,

+  M_APP13 = 0xed,

+  M_APP14 = 0xee,

+  M_APP15 = 0xef,

+  

+  M_JPG0  = 0xf0,

+  M_JPG13 = 0xfd,

+  M_COM   = 0xfe,

+  

+  M_TEM   = 0x01,

+  

+  M_ERROR = 0x100

+} JPEG_MARKER;

+

+

+/*

+ * Basic output routines.

+ *

+ * Note that we do not support suspension while writing a marker.

+ * Therefore, an application using suspension must ensure that there is

+ * enough buffer space for the initial markers (typ. 600-700 bytes) before

+ * calling jpeg_start_compress, and enough space to write the trailing EOI

+ * (a few bytes) before calling jpeg_finish_compress.  Multipass compression

+ * modes are not supported at all with suspension, so those two are the only

+ * points where markers will be written.

+ */

+

+LOCAL void

+emit_byte (j_compress_ptr cinfo, int val)

+/* Emit a byte */

+{

+  struct jpeg_destination_mgr * dest = cinfo->dest;

+

+  *(dest->next_output_byte)++ = (JOCTET) val;

+  if (--dest->free_in_buffer == 0) {

+    if (! (*dest->empty_output_buffer) (cinfo))

+      ERREXIT(cinfo, JERR_CANT_SUSPEND);

+  }

+}

+

+

+LOCAL void

+emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)

+/* Emit a marker code */

+{

+  emit_byte(cinfo, 0xFF);

+  emit_byte(cinfo, (int) mark);

+}

+

+

+LOCAL void

+emit_2bytes (j_compress_ptr cinfo, int value)

+/* Emit a 2-byte integer; these are always MSB first in JPEG files */

+{

+  emit_byte(cinfo, (value >> 8) & 0xFF);

+  emit_byte(cinfo, value & 0xFF);

+}

+

+

+/*

+ * Routines to write specific marker types.

+ */

+

+LOCAL int

+emit_dqt (j_compress_ptr cinfo, int index)

+/* Emit a DQT marker */

+/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */

+{

+  JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];

+  int prec;

+  int i;

+

+  if (qtbl == NULL)

+    ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index);

+

+  prec = 0;

+  for (i = 0; i < DCTSIZE2; i++) {

+    if (qtbl->quantval[i] > 255)

+      prec = 1;

+  }

+

+  if (! qtbl->sent_table) {

+    emit_marker(cinfo, M_DQT);

+

+    emit_2bytes(cinfo, prec ? DCTSIZE2*2 + 1 + 2 : DCTSIZE2 + 1 + 2);

+

+    emit_byte(cinfo, index + (prec<<4));

+

+    for (i = 0; i < DCTSIZE2; i++) {

+      if (prec)

+	emit_byte(cinfo, qtbl->quantval[i] >> 8);

+      emit_byte(cinfo, qtbl->quantval[i] & 0xFF);

+    }

+

+    qtbl->sent_table = TRUE;

+  }

+

+  return prec;

+}

+

+

+LOCAL void

+emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)

+/* Emit a DHT marker */

+{

+  JHUFF_TBL * htbl;

+  int length, i;

+  

+  if (is_ac) {

+    htbl = cinfo->ac_huff_tbl_ptrs[index];

+    index += 0x10;		/* output index has AC bit set */

+  } else {

+    htbl = cinfo->dc_huff_tbl_ptrs[index];

+  }

+

+  if (htbl == NULL)

+    ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index);

+  

+  if (! htbl->sent_table) {

+    emit_marker(cinfo, M_DHT);

+    

+    length = 0;

+    for (i = 1; i <= 16; i++)

+      length += htbl->bits[i];

+    

+    emit_2bytes(cinfo, length + 2 + 1 + 16);

+    emit_byte(cinfo, index);

+    

+    for (i = 1; i <= 16; i++)

+      emit_byte(cinfo, htbl->bits[i]);

+    

+    for (i = 0; i < length; i++)

+      emit_byte(cinfo, htbl->huffval[i]);

+    

+    htbl->sent_table = TRUE;

+  }

+}

+

+

+LOCAL void

+emit_dac (j_compress_ptr cinfo)

+/* Emit a DAC marker */

+/* Since the useful info is so small, we want to emit all the tables in */

+/* one DAC marker.  Therefore this routine does its own scan of the table. */

+{

+#ifdef C_ARITH_CODING_SUPPORTED

+  char dc_in_use[NUM_ARITH_TBLS];

+  char ac_in_use[NUM_ARITH_TBLS];

+  int length, i;

+  jpeg_component_info *compptr;

+  

+  for (i = 0; i < NUM_ARITH_TBLS; i++)

+    dc_in_use[i] = ac_in_use[i] = 0;

+  

+  for (i = 0; i < cinfo->comps_in_scan; i++) {

+    compptr = cinfo->cur_comp_info[i];

+    dc_in_use[compptr->dc_tbl_no] = 1;

+    ac_in_use[compptr->ac_tbl_no] = 1;

+  }

+  

+  length = 0;

+  for (i = 0; i < NUM_ARITH_TBLS; i++)

+    length += dc_in_use[i] + ac_in_use[i];

+  

+  emit_marker(cinfo, M_DAC);

+  

+  emit_2bytes(cinfo, length*2 + 2);

+  

+  for (i = 0; i < NUM_ARITH_TBLS; i++) {

+    if (dc_in_use[i]) {

+      emit_byte(cinfo, i);

+      emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));

+    }

+    if (ac_in_use[i]) {

+      emit_byte(cinfo, i + 0x10);

+      emit_byte(cinfo, cinfo->arith_ac_K[i]);

+    }

+  }

+#endif /* C_ARITH_CODING_SUPPORTED */

+}

+

+

+LOCAL void

+emit_dri (j_compress_ptr cinfo)

+/* Emit a DRI marker */

+{

+  emit_marker(cinfo, M_DRI);

+  

+  emit_2bytes(cinfo, 4);	/* fixed length */

+

+  emit_2bytes(cinfo, (int) cinfo->restart_interval);

+}

+

+

+LOCAL void

+emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)

+/* Emit a SOF marker */

+{

+  int ci;

+  jpeg_component_info *compptr;

+  

+  emit_marker(cinfo, code);

+  

+  emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */

+

+  /* Make sure image isn't bigger than SOF field can handle */

+  if ((long) cinfo->image_height > 65535L ||

+      (long) cinfo->image_width > 65535L)

+    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535);

+

+  emit_byte(cinfo, cinfo->data_precision);

+  emit_2bytes(cinfo, (int) cinfo->image_height);

+  emit_2bytes(cinfo, (int) cinfo->image_width);

+

+  emit_byte(cinfo, cinfo->num_components);

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    emit_byte(cinfo, compptr->component_id);

+    emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);

+    emit_byte(cinfo, compptr->quant_tbl_no);

+  }

+}

+

+

+LOCAL void

+emit_sos (j_compress_ptr cinfo)

+/* Emit a SOS marker */

+{

+  int i, td, ta;

+  jpeg_component_info *compptr;

+  

+  emit_marker(cinfo, M_SOS);

+  

+  emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */

+  

+  emit_byte(cinfo, cinfo->comps_in_scan);

+  

+  for (i = 0; i < cinfo->comps_in_scan; i++) {

+    compptr = cinfo->cur_comp_info[i];

+    emit_byte(cinfo, compptr->component_id);

+    td = compptr->dc_tbl_no;

+    ta = compptr->ac_tbl_no;

+    if (cinfo->progressive_mode) {

+      /* Progressive mode: only DC or only AC tables are used in one scan;

+       * furthermore, Huffman coding of DC refinement uses no table at all.

+       * We emit 0 for unused field(s); this is recommended by the P&M text

+       * but does not seem to be specified in the standard.

+       */

+      if (cinfo->Ss == 0) {

+	ta = 0;			/* DC scan */

+	if (cinfo->Ah != 0 && !cinfo->arith_code)

+	  td = 0;		/* no DC table either */

+      } else {

+	td = 0;			/* AC scan */

+      }

+    }

+    emit_byte(cinfo, (td << 4) + ta);

+  }

+

+  emit_byte(cinfo, cinfo->Ss);

+  emit_byte(cinfo, cinfo->Se);

+  emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);

+}

+

+

+LOCAL void

+emit_jfif_app0 (j_compress_ptr cinfo)

+/* Emit a JFIF-compliant APP0 marker */

+{

+  /*

+   * Length of APP0 block	(2 bytes)

+   * Block ID			(4 bytes - ASCII "JFIF")

+   * Zero byte			(1 byte to terminate the ID string)

+   * Version Major, Minor	(2 bytes - 0x01, 0x01)

+   * Units			(1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)

+   * Xdpu			(2 bytes - dots per unit horizontal)

+   * Ydpu			(2 bytes - dots per unit vertical)

+   * Thumbnail X size		(1 byte)

+   * Thumbnail Y size		(1 byte)

+   */

+  

+  emit_marker(cinfo, M_APP0);

+  

+  emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */

+

+  emit_byte(cinfo, 0x4A);	/* Identifier: ASCII "JFIF" */

+  emit_byte(cinfo, 0x46);

+  emit_byte(cinfo, 0x49);

+  emit_byte(cinfo, 0x46);

+  emit_byte(cinfo, 0);

+  /* We currently emit version code 1.01 since we use no 1.02 features.

+   * This may avoid complaints from some older decoders.

+   */

+  emit_byte(cinfo, 1);		/* Major version */

+  emit_byte(cinfo, 1);		/* Minor version */

+  emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */

+  emit_2bytes(cinfo, (int) cinfo->X_density);

+  emit_2bytes(cinfo, (int) cinfo->Y_density);

+  emit_byte(cinfo, 0);		/* No thumbnail image */

+  emit_byte(cinfo, 0);

+}

+

+

+LOCAL void

+emit_adobe_app14 (j_compress_ptr cinfo)

+/* Emit an Adobe APP14 marker */

+{

+  /*

+   * Length of APP14 block	(2 bytes)

+   * Block ID			(5 bytes - ASCII "Adobe")

+   * Version Number		(2 bytes - currently 100)

+   * Flags0			(2 bytes - currently 0)

+   * Flags1			(2 bytes - currently 0)

+   * Color transform		(1 byte)

+   *

+   * Although Adobe TN 5116 mentions Version = 101, all the Adobe files

+   * now in circulation seem to use Version = 100, so that's what we write.

+   *

+   * We write the color transform byte as 1 if the JPEG color space is

+   * YCbCr, 2 if it's YCCK, 0 otherwise.  Adobe's definition has to do with

+   * whether the encoder performed a transformation, which is pretty useless.

+   */

+  

+  emit_marker(cinfo, M_APP14);

+  

+  emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */

+

+  emit_byte(cinfo, 0x41);	/* Identifier: ASCII "Adobe" */

+  emit_byte(cinfo, 0x64);

+  emit_byte(cinfo, 0x6F);

+  emit_byte(cinfo, 0x62);

+  emit_byte(cinfo, 0x65);

+  emit_2bytes(cinfo, 100);	/* Version */

+  emit_2bytes(cinfo, 0);	/* Flags0 */

+  emit_2bytes(cinfo, 0);	/* Flags1 */

+  switch (cinfo->jpeg_color_space) {

+  case JCS_YCbCr:

+    emit_byte(cinfo, 1);	/* Color transform = 1 */

+    break;

+  case JCS_YCCK:

+    emit_byte(cinfo, 2);	/* Color transform = 2 */

+    break;

+  default:

+    emit_byte(cinfo, 0);	/* Color transform = 0 */

+    break;

+  }

+}

+

+

+/*

+ * This routine is exported for possible use by applications.

+ * The intended use is to emit COM or APPn markers after calling

+ * jpeg_start_compress() and before the first jpeg_write_scanlines() call

+ * (hence, after write_file_header but before write_frame_header).

+ * Other uses are not guaranteed to produce desirable results.

+ */

+

+METHODDEF void

+write_any_marker (j_compress_ptr cinfo, int marker,

+		  const JOCTET *dataptr, unsigned int datalen)

+/* Emit an arbitrary marker with parameters */

+{

+  if (datalen <= (unsigned int) 65533) { /* safety check */

+    emit_marker(cinfo, (JPEG_MARKER) marker);

+  

+    emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */

+

+    while (datalen--) {

+      emit_byte(cinfo, *dataptr);

+      dataptr++;

+    }

+  }

+}

+

+

+/*

+ * Write datastream header.

+ * This consists of an SOI and optional APPn markers.

+ * We recommend use of the JFIF marker, but not the Adobe marker,

+ * when using YCbCr or grayscale data.  The JFIF marker should NOT

+ * be used for any other JPEG colorspace.  The Adobe marker is helpful

+ * to distinguish RGB, CMYK, and YCCK colorspaces.

+ * Note that an application can write additional header markers after

+ * jpeg_start_compress returns.

+ */

+

+METHODDEF void

+write_file_header (j_compress_ptr cinfo)

+{

+  emit_marker(cinfo, M_SOI);	/* first the SOI */

+

+  if (cinfo->write_JFIF_header)	/* next an optional JFIF APP0 */

+    emit_jfif_app0(cinfo);

+  if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */

+    emit_adobe_app14(cinfo);

+}

+

+

+/*

+ * Write frame header.

+ * This consists of DQT and SOFn markers.

+ * Note that we do not emit the SOF until we have emitted the DQT(s).

+ * This avoids compatibility problems with incorrect implementations that

+ * try to error-check the quant table numbers as soon as they see the SOF.

+ */

+

+METHODDEF void

+write_frame_header (j_compress_ptr cinfo)

+{

+  int ci, prec;

+  boolean is_baseline;

+  jpeg_component_info *compptr;

+  

+  /* Emit DQT for each quantization table.

+   * Note that emit_dqt() suppresses any duplicate tables.

+   */

+  prec = 0;

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    prec += emit_dqt(cinfo, compptr->quant_tbl_no);

+  }

+  /* now prec is nonzero iff there are any 16-bit quant tables. */

+

+  /* Check for a non-baseline specification.

+   * Note we assume that Huffman table numbers won't be changed later.

+   */

+  if (cinfo->arith_code || cinfo->progressive_mode ||

+      cinfo->data_precision != 8) {

+    is_baseline = FALSE;

+  } else {

+    is_baseline = TRUE;

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)

+	is_baseline = FALSE;

+    }

+    if (prec && is_baseline) {

+      is_baseline = FALSE;

+      /* If it's baseline except for quantizer size, warn the user */

+      TRACEMS(cinfo, 0, JTRC_16BIT_TABLES);

+    }

+  }

+

+  /* Emit the proper SOF marker */

+  if (cinfo->arith_code) {

+    emit_sof(cinfo, M_SOF9);	/* SOF code for arithmetic coding */

+  } else {

+    if (cinfo->progressive_mode)

+      emit_sof(cinfo, M_SOF2);	/* SOF code for progressive Huffman */

+    else if (is_baseline)

+      emit_sof(cinfo, M_SOF0);	/* SOF code for baseline implementation */

+    else

+      emit_sof(cinfo, M_SOF1);	/* SOF code for non-baseline Huffman file */

+  }

+}

+

+

+/*

+ * Write scan header.

+ * This consists of DHT or DAC markers, optional DRI, and SOS.

+ * Compressed data will be written following the SOS.

+ */

+

+METHODDEF void

+write_scan_header (j_compress_ptr cinfo)

+{

+  int i;

+  jpeg_component_info *compptr;

+

+  if (cinfo->arith_code) {

+    /* Emit arith conditioning info.  We may have some duplication

+     * if the file has multiple scans, but it's so small it's hardly

+     * worth worrying about.

+     */

+    emit_dac(cinfo);

+  } else {

+    /* Emit Huffman tables.

+     * Note that emit_dht() suppresses any duplicate tables.

+     */

+    for (i = 0; i < cinfo->comps_in_scan; i++) {

+      compptr = cinfo->cur_comp_info[i];

+      if (cinfo->progressive_mode) {

+	/* Progressive mode: only DC or only AC tables are used in one scan */

+	if (cinfo->Ss == 0) {

+	  if (cinfo->Ah == 0)	/* DC needs no table for refinement scan */

+	    emit_dht(cinfo, compptr->dc_tbl_no, FALSE);

+	} else {

+	  emit_dht(cinfo, compptr->ac_tbl_no, TRUE);

+	}

+      } else {

+	/* Sequential mode: need both DC and AC tables */

+	emit_dht(cinfo, compptr->dc_tbl_no, FALSE);

+	emit_dht(cinfo, compptr->ac_tbl_no, TRUE);

+      }

+    }

+  }

+

+  /* Emit DRI if required --- note that DRI value could change for each scan.

+   * If it doesn't, a tiny amount of space is wasted in multiple-scan files.

+   * We assume DRI will never be nonzero for one scan and zero for a later one.

+   */

+  if (cinfo->restart_interval)

+    emit_dri(cinfo);

+

+  emit_sos(cinfo);

+}

+

+

+/*

+ * Write datastream trailer.

+ */

+

+METHODDEF void

+write_file_trailer (j_compress_ptr cinfo)

+{

+  emit_marker(cinfo, M_EOI);

+}

+

+

+/*

+ * Write an abbreviated table-specification datastream.

+ * This consists of SOI, DQT and DHT tables, and EOI.

+ * Any table that is defined and not marked sent_table = TRUE will be

+ * emitted.  Note that all tables will be marked sent_table = TRUE at exit.

+ */

+

+METHODDEF void

+write_tables_only (j_compress_ptr cinfo)

+{

+  int i;

+

+  emit_marker(cinfo, M_SOI);

+

+  for (i = 0; i < NUM_QUANT_TBLS; i++) {

+    if (cinfo->quant_tbl_ptrs[i] != NULL)

+      (void) emit_dqt(cinfo, i);

+  }

+

+  if (! cinfo->arith_code) {

+    for (i = 0; i < NUM_HUFF_TBLS; i++) {

+      if (cinfo->dc_huff_tbl_ptrs[i] != NULL)

+	emit_dht(cinfo, i, FALSE);

+      if (cinfo->ac_huff_tbl_ptrs[i] != NULL)

+	emit_dht(cinfo, i, TRUE);

+    }

+  }

+

+  emit_marker(cinfo, M_EOI);

+}

+

+

+/*

+ * Initialize the marker writer module.

+ */

+

+GLOBAL void

+jinit_marker_writer (j_compress_ptr cinfo)

+{

+  /* Create the subobject */

+  cinfo->marker = (struct jpeg_marker_writer *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(struct jpeg_marker_writer));

+  /* Initialize method pointers */

+  cinfo->marker->write_any_marker = write_any_marker;

+  cinfo->marker->write_file_header = write_file_header;

+  cinfo->marker->write_frame_header = write_frame_header;

+  cinfo->marker->write_scan_header = write_scan_header;

+  cinfo->marker->write_file_trailer = write_file_trailer;

+  cinfo->marker->write_tables_only = write_tables_only;

+}

diff --git a/code/jpeg-6/jcmaster.c b/code/jpeg-6/jcmaster.c
new file mode 100755
index 0000000..6be2fd0
--- /dev/null
+++ b/code/jpeg-6/jcmaster.c
@@ -0,0 +1,578 @@
+/*

+ * jcmaster.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains master control logic for the JPEG compressor.

+ * These routines are concerned with parameter validation, initial setup,

+ * and inter-pass control (determining the number of passes and the work 

+ * to be done in each pass).

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private state */

+

+typedef enum {

+	main_pass,		/* input data, also do first output step */

+	huff_opt_pass,		/* Huffman code optimization pass */

+	output_pass		/* data output pass */

+} c_pass_type;

+

+typedef struct {

+  struct jpeg_comp_master pub;	/* public fields */

+

+  c_pass_type pass_type;	/* the type of the current pass */

+

+  int pass_number;		/* # of passes completed */

+  int total_passes;		/* total # of passes needed */

+

+  int scan_number;		/* current index in scan_info[] */

+} my_comp_master;

+

+typedef my_comp_master * my_master_ptr;

+

+

+/*

+ * Support routines that do various essential calculations.

+ */

+

+LOCAL void

+initial_setup (j_compress_ptr cinfo)

+/* Do computations that are needed before master selection phase */

+{

+  int ci;

+  jpeg_component_info *compptr;

+  long samplesperrow;

+  JDIMENSION jd_samplesperrow;

+

+  /* Sanity check on image dimensions */

+  if (cinfo->image_height <= 0 || cinfo->image_width <= 0

+      || cinfo->num_components <= 0 || cinfo->input_components <= 0)

+    ERREXIT(cinfo, JERR_EMPTY_IMAGE);

+

+  /* Make sure image isn't bigger than I can handle */

+  if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||

+      (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)

+    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);

+

+  /* Width of an input scanline must be representable as JDIMENSION. */

+  samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;

+  jd_samplesperrow = (JDIMENSION) samplesperrow;

+  if ((long) jd_samplesperrow != samplesperrow)

+    ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);

+

+  /* For now, precision must match compiled-in value... */

+  if (cinfo->data_precision != BITS_IN_JSAMPLE)

+    ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);

+

+  /* Check that number of components won't exceed internal array sizes */

+  if (cinfo->num_components > MAX_COMPONENTS)

+    ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,

+	     MAX_COMPONENTS);

+

+  /* Compute maximum sampling factors; check factor validity */

+  cinfo->max_h_samp_factor = 1;

+  cinfo->max_v_samp_factor = 1;

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||

+	compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)

+      ERREXIT(cinfo, JERR_BAD_SAMPLING);

+    cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,

+				   compptr->h_samp_factor);

+    cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,

+				   compptr->v_samp_factor);

+  }

+

+  /* Compute dimensions of components */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Fill in the correct component_index value; don't rely on application */

+    compptr->component_index = ci;

+    /* For compression, we never do DCT scaling. */

+    compptr->DCT_scaled_size = DCTSIZE;

+    /* Size in DCT blocks */

+    compptr->width_in_blocks = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,

+		    (long) (cinfo->max_h_samp_factor * DCTSIZE));

+    compptr->height_in_blocks = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,

+		    (long) (cinfo->max_v_samp_factor * DCTSIZE));

+    /* Size in samples */

+    compptr->downsampled_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,

+		    (long) cinfo->max_h_samp_factor);

+    compptr->downsampled_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,

+		    (long) cinfo->max_v_samp_factor);

+    /* Mark component needed (this flag isn't actually used for compression) */

+    compptr->component_needed = TRUE;

+  }

+

+  /* Compute number of fully interleaved MCU rows (number of times that

+   * main controller will call coefficient controller).

+   */

+  cinfo->total_iMCU_rows = (JDIMENSION)

+    jdiv_round_up((long) cinfo->image_height,

+		  (long) (cinfo->max_v_samp_factor*DCTSIZE));

+}

+

+

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+

+LOCAL void

+validate_script (j_compress_ptr cinfo)

+/* Verify that the scan script in cinfo->scan_info[] is valid; also

+ * determine whether it uses progressive JPEG, and set cinfo->progressive_mode.

+ */

+{

+  const jpeg_scan_info * scanptr;

+  int scanno, ncomps, ci, coefi, thisi;

+  int Ss, Se, Ah, Al;

+  boolean component_sent[MAX_COMPONENTS];

+#ifdef C_PROGRESSIVE_SUPPORTED

+  int * last_bitpos_ptr;

+  int last_bitpos[MAX_COMPONENTS][DCTSIZE2];

+  /* -1 until that coefficient has been seen; then last Al for it */

+#endif

+

+  if (cinfo->num_scans <= 0)

+    ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);

+

+  /* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;

+   * for progressive JPEG, no scan can have this.

+   */

+  scanptr = cinfo->scan_info;

+  if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {

+#ifdef C_PROGRESSIVE_SUPPORTED

+    cinfo->progressive_mode = TRUE;

+    last_bitpos_ptr = & last_bitpos[0][0];

+    for (ci = 0; ci < cinfo->num_components; ci++) 

+      for (coefi = 0; coefi < DCTSIZE2; coefi++)

+	*last_bitpos_ptr++ = -1;

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+  } else {

+    cinfo->progressive_mode = FALSE;

+    for (ci = 0; ci < cinfo->num_components; ci++) 

+      component_sent[ci] = FALSE;

+  }

+

+  for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {

+    /* Validate component indexes */

+    ncomps = scanptr->comps_in_scan;

+    if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)

+      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);

+    for (ci = 0; ci < ncomps; ci++) {

+      thisi = scanptr->component_index[ci];

+      if (thisi < 0 || thisi >= cinfo->num_components)

+	ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);

+      /* Components must appear in SOF order within each scan */

+      if (ci > 0 && thisi <= scanptr->component_index[ci-1])

+	ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);

+    }

+    /* Validate progression parameters */

+    Ss = scanptr->Ss;

+    Se = scanptr->Se;

+    Ah = scanptr->Ah;

+    Al = scanptr->Al;

+    if (cinfo->progressive_mode) {

+#ifdef C_PROGRESSIVE_SUPPORTED

+      if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||

+	  Ah < 0 || Ah > 13 || Al < 0 || Al > 13)

+	ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+      if (Ss == 0) {

+	if (Se != 0)		/* DC and AC together not OK */

+	  ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+      } else {

+	if (ncomps != 1)	/* AC scans must be for only one component */

+	  ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+      }

+      for (ci = 0; ci < ncomps; ci++) {

+	last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];

+	if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */

+	  ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+	for (coefi = Ss; coefi <= Se; coefi++) {

+	  if (last_bitpos_ptr[coefi] < 0) {

+	    /* first scan of this coefficient */

+	    if (Ah != 0)

+	      ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+	  } else {

+	    /* not first scan */

+	    if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)

+	      ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+	  }

+	  last_bitpos_ptr[coefi] = Al;

+	}

+      }

+#endif

+    } else {

+      /* For sequential JPEG, all progression parameters must be these: */

+      if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)

+	ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);

+      /* Make sure components are not sent twice */

+      for (ci = 0; ci < ncomps; ci++) {

+	thisi = scanptr->component_index[ci];

+	if (component_sent[thisi])

+	  ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);

+	component_sent[thisi] = TRUE;

+      }

+    }

+  }

+

+  /* Now verify that everything got sent. */

+  if (cinfo->progressive_mode) {

+#ifdef C_PROGRESSIVE_SUPPORTED

+    /* For progressive mode, we only check that at least some DC data

+     * got sent for each component; the spec does not require that all bits

+     * of all coefficients be transmitted.  Would it be wiser to enforce

+     * transmission of all coefficient bits??

+     */

+    for (ci = 0; ci < cinfo->num_components; ci++) {

+      if (last_bitpos[ci][0] < 0)

+	ERREXIT(cinfo, JERR_MISSING_DATA);

+    }

+#endif

+  } else {

+    for (ci = 0; ci < cinfo->num_components; ci++) {

+      if (! component_sent[ci])

+	ERREXIT(cinfo, JERR_MISSING_DATA);

+    }

+  }

+}

+

+#endif /* C_MULTISCAN_FILES_SUPPORTED */

+

+

+LOCAL void

+select_scan_parameters (j_compress_ptr cinfo)

+/* Set up the scan parameters for the current scan */

+{

+  int ci;

+

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+  if (cinfo->scan_info != NULL) {

+    /* Prepare for current scan --- the script is already validated */

+    my_master_ptr master = (my_master_ptr) cinfo->master;

+    const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;

+

+    cinfo->comps_in_scan = scanptr->comps_in_scan;

+    for (ci = 0; ci < scanptr->comps_in_scan; ci++) {

+      cinfo->cur_comp_info[ci] =

+	&cinfo->comp_info[scanptr->component_index[ci]];

+    }

+    cinfo->Ss = scanptr->Ss;

+    cinfo->Se = scanptr->Se;

+    cinfo->Ah = scanptr->Ah;

+    cinfo->Al = scanptr->Al;

+  }

+  else

+#endif

+  {

+    /* Prepare for single sequential-JPEG scan containing all components */

+    if (cinfo->num_components > MAX_COMPS_IN_SCAN)

+      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,

+	       MAX_COMPS_IN_SCAN);

+    cinfo->comps_in_scan = cinfo->num_components;

+    for (ci = 0; ci < cinfo->num_components; ci++) {

+      cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];

+    }

+    cinfo->Ss = 0;

+    cinfo->Se = DCTSIZE2-1;

+    cinfo->Ah = 0;

+    cinfo->Al = 0;

+  }

+}

+

+

+LOCAL void

+per_scan_setup (j_compress_ptr cinfo)

+/* Do computations that are needed before processing a JPEG scan */

+/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */

+{

+  int ci, mcublks, tmp;

+  jpeg_component_info *compptr;

+  

+  if (cinfo->comps_in_scan == 1) {

+    

+    /* Noninterleaved (single-component) scan */

+    compptr = cinfo->cur_comp_info[0];

+    

+    /* Overall image size in MCUs */

+    cinfo->MCUs_per_row = compptr->width_in_blocks;

+    cinfo->MCU_rows_in_scan = compptr->height_in_blocks;

+    

+    /* For noninterleaved scan, always one block per MCU */

+    compptr->MCU_width = 1;

+    compptr->MCU_height = 1;

+    compptr->MCU_blocks = 1;

+    compptr->MCU_sample_width = DCTSIZE;

+    compptr->last_col_width = 1;

+    /* For noninterleaved scans, it is convenient to define last_row_height

+     * as the number of block rows present in the last iMCU row.

+     */

+    tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);

+    if (tmp == 0) tmp = compptr->v_samp_factor;

+    compptr->last_row_height = tmp;

+    

+    /* Prepare array describing MCU composition */

+    cinfo->blocks_in_MCU = 1;

+    cinfo->MCU_membership[0] = 0;

+    

+  } else {

+    

+    /* Interleaved (multi-component) scan */

+    if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)

+      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,

+	       MAX_COMPS_IN_SCAN);

+    

+    /* Overall image size in MCUs */

+    cinfo->MCUs_per_row = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width,

+		    (long) (cinfo->max_h_samp_factor*DCTSIZE));

+    cinfo->MCU_rows_in_scan = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height,

+		    (long) (cinfo->max_v_samp_factor*DCTSIZE));

+    

+    cinfo->blocks_in_MCU = 0;

+    

+    for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+      compptr = cinfo->cur_comp_info[ci];

+      /* Sampling factors give # of blocks of component in each MCU */

+      compptr->MCU_width = compptr->h_samp_factor;

+      compptr->MCU_height = compptr->v_samp_factor;

+      compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;

+      compptr->MCU_sample_width = compptr->MCU_width * DCTSIZE;

+      /* Figure number of non-dummy blocks in last MCU column & row */

+      tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);

+      if (tmp == 0) tmp = compptr->MCU_width;

+      compptr->last_col_width = tmp;

+      tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);

+      if (tmp == 0) tmp = compptr->MCU_height;

+      compptr->last_row_height = tmp;

+      /* Prepare array describing MCU composition */

+      mcublks = compptr->MCU_blocks;

+      if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)

+	ERREXIT(cinfo, JERR_BAD_MCU_SIZE);

+      while (mcublks-- > 0) {

+	cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;

+      }

+    }

+    

+  }

+

+  /* Convert restart specified in rows to actual MCU count. */

+  /* Note that count must fit in 16 bits, so we provide limiting. */

+  if (cinfo->restart_in_rows > 0) {

+    long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;

+    cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);

+  }

+}

+

+

+/*

+ * Per-pass setup.

+ * This is called at the beginning of each pass.  We determine which modules

+ * will be active during this pass and give them appropriate start_pass calls.

+ * We also set is_last_pass to indicate whether any more passes will be

+ * required.

+ */

+

+METHODDEF void

+prepare_for_pass (j_compress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+

+  switch (master->pass_type) {

+  case main_pass:

+    /* Initial pass: will collect input data, and do either Huffman

+     * optimization or data output for the first scan.

+     */

+    select_scan_parameters(cinfo);

+    per_scan_setup(cinfo);

+    if (! cinfo->raw_data_in) {

+      (*cinfo->cconvert->start_pass) (cinfo);

+      (*cinfo->downsample->start_pass) (cinfo);

+      (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);

+    }

+    (*cinfo->fdct->start_pass) (cinfo);

+    (*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);

+    (*cinfo->coef->start_pass) (cinfo,

+				(master->total_passes > 1 ?

+				 JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));

+    (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);

+    if (cinfo->optimize_coding) {

+      /* No immediate data output; postpone writing frame/scan headers */

+      master->pub.call_pass_startup = FALSE;

+    } else {

+      /* Will write frame/scan headers at first jpeg_write_scanlines call */

+      master->pub.call_pass_startup = TRUE;

+    }

+    break;

+#ifdef ENTROPY_OPT_SUPPORTED

+  case huff_opt_pass:

+    /* Do Huffman optimization for a scan after the first one. */

+    select_scan_parameters(cinfo);

+    per_scan_setup(cinfo);

+    if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code) {

+      (*cinfo->entropy->start_pass) (cinfo, TRUE);

+      (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);

+      master->pub.call_pass_startup = FALSE;

+      break;

+    }

+    /* Special case: Huffman DC refinement scans need no Huffman table

+     * and therefore we can skip the optimization pass for them.

+     */

+    master->pass_type = output_pass;

+    master->pass_number++;

+    /*FALLTHROUGH*/

+#endif

+  case output_pass:

+    /* Do a data-output pass. */

+    /* We need not repeat per-scan setup if prior optimization pass did it. */

+    if (! cinfo->optimize_coding) {

+      select_scan_parameters(cinfo);

+      per_scan_setup(cinfo);

+    }

+    (*cinfo->entropy->start_pass) (cinfo, FALSE);

+    (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);

+    /* We emit frame/scan headers now */

+    if (master->scan_number == 0)

+      (*cinfo->marker->write_frame_header) (cinfo);

+    (*cinfo->marker->write_scan_header) (cinfo);

+    master->pub.call_pass_startup = FALSE;

+    break;

+  default:

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+  }

+

+  master->pub.is_last_pass = (master->pass_number == master->total_passes-1);

+

+  /* Set up progress monitor's pass info if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->completed_passes = master->pass_number;

+    cinfo->progress->total_passes = master->total_passes;

+  }

+}

+

+

+/*

+ * Special start-of-pass hook.

+ * This is called by jpeg_write_scanlines if call_pass_startup is TRUE.

+ * In single-pass processing, we need this hook because we don't want to

+ * write frame/scan headers during jpeg_start_compress; we want to let the

+ * application write COM markers etc. between jpeg_start_compress and the

+ * jpeg_write_scanlines loop.

+ * In multi-pass processing, this routine is not used.

+ */

+

+METHODDEF void

+pass_startup (j_compress_ptr cinfo)

+{

+  cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */

+

+  (*cinfo->marker->write_frame_header) (cinfo);

+  (*cinfo->marker->write_scan_header) (cinfo);

+}

+

+

+/*

+ * Finish up at end of pass.

+ */

+

+METHODDEF void

+finish_pass_master (j_compress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+

+  /* The entropy coder always needs an end-of-pass call,

+   * either to analyze statistics or to flush its output buffer.

+   */

+  (*cinfo->entropy->finish_pass) (cinfo);

+

+  /* Update state for next pass */

+  switch (master->pass_type) {

+  case main_pass:

+    /* next pass is either output of scan 0 (after optimization)

+     * or output of scan 1 (if no optimization).

+     */

+    master->pass_type = output_pass;

+    if (! cinfo->optimize_coding)

+      master->scan_number++;

+    break;

+  case huff_opt_pass:

+    /* next pass is always output of current scan */

+    master->pass_type = output_pass;

+    break;

+  case output_pass:

+    /* next pass is either optimization or output of next scan */

+    if (cinfo->optimize_coding)

+      master->pass_type = huff_opt_pass;

+    master->scan_number++;

+    break;

+  }

+

+  master->pass_number++;

+}

+

+

+/*

+ * Initialize master compression control.

+ */

+

+GLOBAL void

+jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)

+{

+  my_master_ptr master;

+

+  master = (my_master_ptr)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(my_comp_master));

+  cinfo->master = (struct jpeg_comp_master *) master;

+  master->pub.prepare_for_pass = prepare_for_pass;

+  master->pub.pass_startup = pass_startup;

+  master->pub.finish_pass = finish_pass_master;

+  master->pub.is_last_pass = FALSE;

+

+  /* Validate parameters, determine derived values */

+  initial_setup(cinfo);

+

+  if (cinfo->scan_info != NULL) {

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+    validate_script(cinfo);

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+  } else {

+    cinfo->progressive_mode = FALSE;

+    cinfo->num_scans = 1;

+  }

+

+  if (cinfo->progressive_mode)	/*  TEMPORARY HACK ??? */

+    cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */

+

+  /* Initialize my private state */

+  if (transcode_only) {

+    /* no main pass in transcoding */

+    if (cinfo->optimize_coding)

+      master->pass_type = huff_opt_pass;

+    else

+      master->pass_type = output_pass;

+  } else {

+    /* for normal compression, first pass is always this type: */

+    master->pass_type = main_pass;

+  }

+  master->scan_number = 0;

+  master->pass_number = 0;

+  if (cinfo->optimize_coding)

+    master->total_passes = cinfo->num_scans * 2;

+  else

+    master->total_passes = cinfo->num_scans;

+}

diff --git a/code/jpeg-6/jcomapi.c b/code/jpeg-6/jcomapi.c
new file mode 100755
index 0000000..8f417c0
--- /dev/null
+++ b/code/jpeg-6/jcomapi.c
@@ -0,0 +1,94 @@
+/*

+ * jcomapi.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface routines that are used for both

+ * compression and decompression.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Abort processing of a JPEG compression or decompression operation,

+ * but don't destroy the object itself.

+ *

+ * For this, we merely clean up all the nonpermanent memory pools.

+ * Note that temp files (virtual arrays) are not allowed to belong to

+ * the permanent pool, so we will be able to close all temp files here.

+ * Closing a data source or destination, if necessary, is the application's

+ * responsibility.

+ */

+

+GLOBAL void

+jpeg_abort (j_common_ptr cinfo)

+{

+  int pool;

+

+  /* Releasing pools in reverse order might help avoid fragmentation

+   * with some (brain-damaged) malloc libraries.

+   */

+  for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {

+    (*cinfo->mem->free_pool) (cinfo, pool);

+  }

+

+  /* Reset overall state for possible reuse of object */

+  cinfo->global_state = (cinfo->is_decompressor ? DSTATE_START : CSTATE_START);

+}

+

+

+/*

+ * Destruction of a JPEG object.

+ *

+ * Everything gets deallocated except the master jpeg_compress_struct itself

+ * and the error manager struct.  Both of these are supplied by the application

+ * and must be freed, if necessary, by the application.  (Often they are on

+ * the stack and so don't need to be freed anyway.)

+ * Closing a data source or destination, if necessary, is the application's

+ * responsibility.

+ */

+

+GLOBAL void

+jpeg_destroy (j_common_ptr cinfo)

+{

+  /* We need only tell the memory manager to release everything. */

+  /* NB: mem pointer is NULL if memory mgr failed to initialize. */

+  if (cinfo->mem != NULL)

+    (*cinfo->mem->self_destruct) (cinfo);

+  cinfo->mem = NULL;		/* be safe if jpeg_destroy is called twice */

+  cinfo->global_state = 0;	/* mark it destroyed */

+}

+

+

+/*

+ * Convenience routines for allocating quantization and Huffman tables.

+ * (Would jutils.c be a more reasonable place to put these?)

+ */

+

+GLOBAL JQUANT_TBL *

+jpeg_alloc_quant_table (j_common_ptr cinfo)

+{

+  JQUANT_TBL *tbl;

+

+  tbl = (JQUANT_TBL *)

+    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));

+  tbl->sent_table = FALSE;	/* make sure this is false in any new table */

+  return tbl;

+}

+

+

+GLOBAL JHUFF_TBL *

+jpeg_alloc_huff_table (j_common_ptr cinfo)

+{

+  JHUFF_TBL *tbl;

+

+  tbl = (JHUFF_TBL *)

+    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));

+  tbl->sent_table = FALSE;	/* make sure this is false in any new table */

+  return tbl;

+}

diff --git a/code/jpeg-6/jconfig.h b/code/jpeg-6/jconfig.h
new file mode 100755
index 0000000..187ecfc
--- /dev/null
+++ b/code/jpeg-6/jconfig.h
@@ -0,0 +1,41 @@
+/* jconfig.wat --- jconfig.h for Watcom C/C++ on MS-DOS or OS/2. */

+/* see jconfig.doc for explanations */

+

+#define HAVE_PROTOTYPES

+#define HAVE_UNSIGNED_CHAR

+#define HAVE_UNSIGNED_SHORT

+/* #define void char */

+/* #define const */

+#define CHAR_IS_UNSIGNED

+#define HAVE_STDDEF_H

+#define HAVE_STDLIB_H

+#undef NEED_BSD_STRINGS

+#undef NEED_SYS_TYPES_H

+#undef NEED_FAR_POINTERS	/* Watcom uses flat 32-bit addressing */

+#undef NEED_SHORT_EXTERNAL_NAMES

+#undef INCOMPLETE_TYPES_BROKEN

+

+#define JDCT_DEFAULT  JDCT_FLOAT

+#define JDCT_FASTEST  JDCT_FLOAT

+

+#ifdef JPEG_INTERNALS

+

+#undef RIGHT_SHIFT_IS_UNSIGNED

+

+#endif /* JPEG_INTERNALS */

+

+#ifdef JPEG_CJPEG_DJPEG

+

+#define BMP_SUPPORTED		/* BMP image file format */

+#define GIF_SUPPORTED		/* GIF image file format */

+#define PPM_SUPPORTED		/* PBMPLUS PPM/PGM image file format */

+#undef RLE_SUPPORTED		/* Utah RLE image file format */

+#define TARGA_SUPPORTED		/* Targa image file format */

+

+#undef TWO_FILE_COMMANDLINE	/* optional */

+#define USE_SETMODE		/* Needed to make one-file style work in Watcom */

+#undef NEED_SIGNAL_CATCHER	/* Define this if you use jmemname.c */

+#undef DONT_USE_B_MODE

+#undef PROGRESS_REPORT		/* optional */

+

+#endif /* JPEG_CJPEG_DJPEG */

diff --git a/code/jpeg-6/jcparam.c b/code/jpeg-6/jcparam.c
new file mode 100755
index 0000000..bf539f9
--- /dev/null
+++ b/code/jpeg-6/jcparam.c
@@ -0,0 +1,575 @@
+/*

+ * jcparam.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains optional default-setting code for the JPEG compressor.

+ * Applications do not have to use this file, but those that don't use it

+ * must know a lot more about the innards of the JPEG code.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Quantization table setup routines

+ */

+

+GLOBAL void

+jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl,

+		      const unsigned int *basic_table,

+		      int scale_factor, boolean force_baseline)

+/* Define a quantization table equal to the basic_table times

+ * a scale factor (given as a percentage).

+ * If force_baseline is TRUE, the computed quantization table entries

+ * are limited to 1..255 for JPEG baseline compatibility.

+ */

+{

+  JQUANT_TBL ** qtblptr = & cinfo->quant_tbl_ptrs[which_tbl];

+  int i;

+  long temp;

+

+  /* Safety check to ensure start_compress not called yet. */

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  if (*qtblptr == NULL)

+    *qtblptr = jpeg_alloc_quant_table((j_common_ptr) cinfo);

+

+  for (i = 0; i < DCTSIZE2; i++) {

+    temp = ((long) basic_table[i] * scale_factor + 50L) / 100L;

+    /* limit the values to the valid range */

+    if (temp <= 0L) temp = 1L;

+    if (temp > 32767L) temp = 32767L; /* max quantizer needed for 12 bits */

+    if (force_baseline && temp > 255L)

+      temp = 255L;		/* limit to baseline range if requested */

+    (*qtblptr)->quantval[i] = (UINT16) temp;

+  }

+

+  /* Initialize sent_table FALSE so table will be written to JPEG file. */

+  (*qtblptr)->sent_table = FALSE;

+}

+

+

+GLOBAL void

+jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor,

+			 boolean force_baseline)

+/* Set or change the 'quality' (quantization) setting, using default tables

+ * and a straight percentage-scaling quality scale.  In most cases it's better

+ * to use jpeg_set_quality (below); this entry point is provided for

+ * applications that insist on a linear percentage scaling.

+ */

+{

+  /* This is the sample quantization table given in the JPEG spec section K.1,

+   * but expressed in zigzag order (as are all of our quant. tables).

+   * The spec says that the values given produce "good" quality, and

+   * when divided by 2, "very good" quality.

+   */

+  static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {

+    16,  11,  12,  14,  12,  10,  16,  14,

+    13,  14,  18,  17,  16,  19,  24,  40,

+    26,  24,  22,  22,  24,  49,  35,  37,

+    29,  40,  58,  51,  61,  60,  57,  51,

+    56,  55,  64,  72,  92,  78,  64,  68,

+    87,  69,  55,  56,  80, 109,  81,  87,

+    95,  98, 103, 104, 103,  62,  77, 113,

+    121, 112, 100, 120,  92, 101, 103,  99

+    };

+  static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {

+    17,  18,  18,  24,  21,  24,  47,  26,

+    26,  47,  99,  66,  56,  66,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99,

+    99,  99,  99,  99,  99,  99,  99,  99

+    };

+

+  /* Set up two quantization tables using the specified scaling */

+  jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,

+		       scale_factor, force_baseline);

+  jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,

+		       scale_factor, force_baseline);

+}

+

+

+GLOBAL int

+jpeg_quality_scaling (int quality)

+/* Convert a user-specified quality rating to a percentage scaling factor

+ * for an underlying quantization table, using our recommended scaling curve.

+ * The input 'quality' factor should be 0 (terrible) to 100 (very good).

+ */

+{

+  /* Safety limit on quality factor.  Convert 0 to 1 to avoid zero divide. */

+  if (quality <= 0) quality = 1;

+  if (quality > 100) quality = 100;

+

+  /* The basic table is used as-is (scaling 100) for a quality of 50.

+   * Qualities 50..100 are converted to scaling percentage 200 - 2*Q;

+   * note that at Q=100 the scaling is 0, which will cause j_add_quant_table

+   * to make all the table entries 1 (hence, no quantization loss).

+   * Qualities 1..50 are converted to scaling percentage 5000/Q.

+   */

+  if (quality < 50)

+    quality = 5000 / quality;

+  else

+    quality = 200 - quality*2;

+

+  return quality;

+}

+

+

+GLOBAL void

+jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline)

+/* Set or change the 'quality' (quantization) setting, using default tables.

+ * This is the standard quality-adjusting entry point for typical user

+ * interfaces; only those who want detailed control over quantization tables

+ * would use the preceding three routines directly.

+ */

+{

+  /* Convert user 0-100 rating to percentage scaling */

+  quality = jpeg_quality_scaling(quality);

+

+  /* Set up standard quality tables */

+  jpeg_set_linear_quality(cinfo, quality, force_baseline);

+}

+

+

+/*

+ * Huffman table setup routines

+ */

+

+LOCAL void

+add_huff_table (j_compress_ptr cinfo,

+		JHUFF_TBL **htblptr, const UINT8 *bits, const UINT8 *val)

+/* Define a Huffman table */

+{

+  if (*htblptr == NULL)

+    *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);

+  

+  MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));

+  MEMCOPY((*htblptr)->huffval, val, SIZEOF((*htblptr)->huffval));

+

+  /* Initialize sent_table FALSE so table will be written to JPEG file. */

+  (*htblptr)->sent_table = FALSE;

+}

+

+

+LOCAL void

+std_huff_tables (j_compress_ptr cinfo)

+/* Set up the standard Huffman tables (cf. JPEG standard section K.3) */

+/* IMPORTANT: these are only valid for 8-bit data precision! */

+{

+  static const UINT8 bits_dc_luminance[17] =

+    { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };

+  static const UINT8 val_dc_luminance[] =

+    { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

+  

+  static const UINT8 bits_dc_chrominance[17] =

+    { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };

+  static const UINT8 val_dc_chrominance[] =

+    { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

+  

+  static const UINT8 bits_ac_luminance[17] =

+    { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };

+  static const UINT8 val_ac_luminance[] =

+    { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,

+      0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,

+      0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,

+      0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,

+      0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,

+      0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,

+      0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,

+      0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,

+      0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,

+      0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,

+      0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,

+      0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,

+      0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,

+      0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,

+      0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,

+      0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,

+      0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,

+      0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,

+      0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,

+      0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

+      0xf9, 0xfa };

+  

+  static const UINT8 bits_ac_chrominance[17] =

+    { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };

+  static const UINT8 val_ac_chrominance[] =

+    { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,

+      0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,

+      0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,

+      0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,

+      0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,

+      0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,

+      0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,

+      0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,

+      0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,

+      0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,

+      0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,

+      0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,

+      0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,

+      0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,

+      0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,

+      0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,

+      0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,

+      0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,

+      0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,

+      0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

+      0xf9, 0xfa };

+  

+  add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[0],

+		 bits_dc_luminance, val_dc_luminance);

+  add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[0],

+		 bits_ac_luminance, val_ac_luminance);

+  add_huff_table(cinfo, &cinfo->dc_huff_tbl_ptrs[1],

+		 bits_dc_chrominance, val_dc_chrominance);

+  add_huff_table(cinfo, &cinfo->ac_huff_tbl_ptrs[1],

+		 bits_ac_chrominance, val_ac_chrominance);

+}

+

+

+/*

+ * Default parameter setup for compression.

+ *

+ * Applications that don't choose to use this routine must do their

+ * own setup of all these parameters.  Alternately, you can call this

+ * to establish defaults and then alter parameters selectively.  This

+ * is the recommended approach since, if we add any new parameters,

+ * your code will still work (they'll be set to reasonable defaults).

+ */

+

+GLOBAL void

+jpeg_set_defaults (j_compress_ptr cinfo)

+{

+  int i;

+

+  /* Safety check to ensure start_compress not called yet. */

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  /* Allocate comp_info array large enough for maximum component count.

+   * Array is made permanent in case application wants to compress

+   * multiple images at same param settings.

+   */

+  if (cinfo->comp_info == NULL)

+    cinfo->comp_info = (jpeg_component_info *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				  MAX_COMPONENTS * SIZEOF(jpeg_component_info));

+

+  /* Initialize everything not dependent on the color space */

+

+  cinfo->data_precision = BITS_IN_JSAMPLE;

+  /* Set up two quantization tables using default quality of 75 */

+  jpeg_set_quality(cinfo, 75, TRUE);

+  /* Set up two Huffman tables */

+  std_huff_tables(cinfo);

+

+  /* Initialize default arithmetic coding conditioning */

+  for (i = 0; i < NUM_ARITH_TBLS; i++) {

+    cinfo->arith_dc_L[i] = 0;

+    cinfo->arith_dc_U[i] = 1;

+    cinfo->arith_ac_K[i] = 5;

+  }

+

+  /* Default is no multiple-scan output */

+  cinfo->scan_info = NULL;

+  cinfo->num_scans = 0;

+

+  /* Expect normal source image, not raw downsampled data */

+  cinfo->raw_data_in = FALSE;

+

+  /* Use Huffman coding, not arithmetic coding, by default */

+  cinfo->arith_code = FALSE;

+

+  /* By default, don't do extra passes to optimize entropy coding */

+  cinfo->optimize_coding = FALSE;

+  /* The standard Huffman tables are only valid for 8-bit data precision.

+   * If the precision is higher, force optimization on so that usable

+   * tables will be computed.  This test can be removed if default tables

+   * are supplied that are valid for the desired precision.

+   */

+  if (cinfo->data_precision > 8)

+    cinfo->optimize_coding = TRUE;

+

+  /* By default, use the simpler non-cosited sampling alignment */

+  cinfo->CCIR601_sampling = FALSE;

+

+  /* No input smoothing */

+  cinfo->smoothing_factor = 0;

+

+  /* DCT algorithm preference */

+  cinfo->dct_method = JDCT_DEFAULT;

+

+  /* No restart markers */

+  cinfo->restart_interval = 0;

+  cinfo->restart_in_rows = 0;

+

+  /* Fill in default JFIF marker parameters.  Note that whether the marker

+   * will actually be written is determined by jpeg_set_colorspace.

+   */

+  cinfo->density_unit = 0;	/* Pixel size is unknown by default */

+  cinfo->X_density = 1;		/* Pixel aspect ratio is square by default */

+  cinfo->Y_density = 1;

+

+  /* Choose JPEG colorspace based on input space, set defaults accordingly */

+

+  jpeg_default_colorspace(cinfo);

+}

+

+

+/*

+ * Select an appropriate JPEG colorspace for in_color_space.

+ */

+

+GLOBAL void

+jpeg_default_colorspace (j_compress_ptr cinfo)

+{

+  switch (cinfo->in_color_space) {

+  case JCS_GRAYSCALE:

+    jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);

+    break;

+  case JCS_RGB:

+    jpeg_set_colorspace(cinfo, JCS_YCbCr);

+    break;

+  case JCS_YCbCr:

+    jpeg_set_colorspace(cinfo, JCS_YCbCr);

+    break;

+  case JCS_CMYK:

+    jpeg_set_colorspace(cinfo, JCS_CMYK); /* By default, no translation */

+    break;

+  case JCS_YCCK:

+    jpeg_set_colorspace(cinfo, JCS_YCCK);

+    break;

+  case JCS_UNKNOWN:

+    jpeg_set_colorspace(cinfo, JCS_UNKNOWN);

+    break;

+  default:

+    ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

+  }

+}

+

+

+/*

+ * Set the JPEG colorspace, and choose colorspace-dependent default values.

+ */

+

+GLOBAL void

+jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace)

+{

+  jpeg_component_info * compptr;

+  int ci;

+

+#define SET_COMP(index,id,hsamp,vsamp,quant,dctbl,actbl)  \

+  (compptr = &cinfo->comp_info[index], \

+   compptr->component_id = (id), \

+   compptr->h_samp_factor = (hsamp), \

+   compptr->v_samp_factor = (vsamp), \

+   compptr->quant_tbl_no = (quant), \

+   compptr->dc_tbl_no = (dctbl), \

+   compptr->ac_tbl_no = (actbl) )

+

+  /* Safety check to ensure start_compress not called yet. */

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  /* For all colorspaces, we use Q and Huff tables 0 for luminance components,

+   * tables 1 for chrominance components.

+   */

+

+  cinfo->jpeg_color_space = colorspace;

+

+  cinfo->write_JFIF_header = FALSE; /* No marker for non-JFIF colorspaces */

+  cinfo->write_Adobe_marker = FALSE; /* write no Adobe marker by default */

+

+  switch (colorspace) {

+  case JCS_GRAYSCALE:

+    cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */

+    cinfo->num_components = 1;

+    /* JFIF specifies component ID 1 */

+    SET_COMP(0, 1, 1,1, 0, 0,0);

+    break;

+  case JCS_RGB:

+    cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag RGB */

+    cinfo->num_components = 3;

+    SET_COMP(0, 0x52 /* 'R' */, 1,1, 0, 0,0);

+    SET_COMP(1, 0x47 /* 'G' */, 1,1, 0, 0,0);

+    SET_COMP(2, 0x42 /* 'B' */, 1,1, 0, 0,0);

+    break;

+  case JCS_YCbCr:

+    cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */

+    cinfo->num_components = 3;

+    /* JFIF specifies component IDs 1,2,3 */

+    /* We default to 2x2 subsamples of chrominance */

+    SET_COMP(0, 1, 2,2, 0, 0,0);

+    SET_COMP(1, 2, 1,1, 1, 1,1);

+    SET_COMP(2, 3, 1,1, 1, 1,1);

+    break;

+  case JCS_CMYK:

+    cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag CMYK */

+    cinfo->num_components = 4;

+    SET_COMP(0, 0x43 /* 'C' */, 1,1, 0, 0,0);

+    SET_COMP(1, 0x4D /* 'M' */, 1,1, 0, 0,0);

+    SET_COMP(2, 0x59 /* 'Y' */, 1,1, 0, 0,0);

+    SET_COMP(3, 0x4B /* 'K' */, 1,1, 0, 0,0);

+    break;

+  case JCS_YCCK:

+    cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag YCCK */

+    cinfo->num_components = 4;

+    SET_COMP(0, 1, 2,2, 0, 0,0);

+    SET_COMP(1, 2, 1,1, 1, 1,1);

+    SET_COMP(2, 3, 1,1, 1, 1,1);

+    SET_COMP(3, 4, 2,2, 0, 0,0);

+    break;

+  case JCS_UNKNOWN:

+    cinfo->num_components = cinfo->input_components;

+    if (cinfo->num_components < 1 || cinfo->num_components > MAX_COMPONENTS)

+      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,

+	       MAX_COMPONENTS);

+    for (ci = 0; ci < cinfo->num_components; ci++) {

+      SET_COMP(ci, ci, 1,1, 0, 0,0);

+    }

+    break;

+  default:

+    ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+  }

+}

+

+

+#ifdef C_PROGRESSIVE_SUPPORTED

+

+LOCAL jpeg_scan_info *

+fill_a_scan (jpeg_scan_info * scanptr, int ci,

+	     int Ss, int Se, int Ah, int Al)

+/* Support routine: generate one scan for specified component */

+{

+  scanptr->comps_in_scan = 1;

+  scanptr->component_index[0] = ci;

+  scanptr->Ss = Ss;

+  scanptr->Se = Se;

+  scanptr->Ah = Ah;

+  scanptr->Al = Al;

+  scanptr++;

+  return scanptr;

+}

+

+LOCAL jpeg_scan_info *

+fill_scans (jpeg_scan_info * scanptr, int ncomps,

+	    int Ss, int Se, int Ah, int Al)

+/* Support routine: generate one scan for each component */

+{

+  int ci;

+

+  for (ci = 0; ci < ncomps; ci++) {

+    scanptr->comps_in_scan = 1;

+    scanptr->component_index[0] = ci;

+    scanptr->Ss = Ss;

+    scanptr->Se = Se;

+    scanptr->Ah = Ah;

+    scanptr->Al = Al;

+    scanptr++;

+  }

+  return scanptr;

+}

+

+LOCAL jpeg_scan_info *

+fill_dc_scans (jpeg_scan_info * scanptr, int ncomps, int Ah, int Al)

+/* Support routine: generate interleaved DC scan if possible, else N scans */

+{

+  int ci;

+

+  if (ncomps <= MAX_COMPS_IN_SCAN) {

+    /* Single interleaved DC scan */

+    scanptr->comps_in_scan = ncomps;

+    for (ci = 0; ci < ncomps; ci++)

+      scanptr->component_index[ci] = ci;

+    scanptr->Ss = scanptr->Se = 0;

+    scanptr->Ah = Ah;

+    scanptr->Al = Al;

+    scanptr++;

+  } else {

+    /* Noninterleaved DC scan for each component */

+    scanptr = fill_scans(scanptr, ncomps, 0, 0, Ah, Al);

+  }

+  return scanptr;

+}

+

+

+/*

+ * Create a recommended progressive-JPEG script.

+ * cinfo->num_components and cinfo->jpeg_color_space must be correct.

+ */

+

+GLOBAL void

+jpeg_simple_progression (j_compress_ptr cinfo)

+{

+  int ncomps = cinfo->num_components;

+  int nscans;

+  jpeg_scan_info * scanptr;

+

+  /* Safety check to ensure start_compress not called yet. */

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  /* Figure space needed for script.  Calculation must match code below! */

+  if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {

+    /* Custom script for YCbCr color images. */

+    nscans = 10;

+  } else {

+    /* All-purpose script for other color spaces. */

+    if (ncomps > MAX_COMPS_IN_SCAN)

+      nscans = 6 * ncomps;	/* 2 DC + 4 AC scans per component */

+    else

+      nscans = 2 + 4 * ncomps;	/* 2 DC scans; 4 AC scans per component */

+  }

+

+  /* Allocate space for script. */

+  /* We use permanent pool just in case application re-uses script. */

+  scanptr = (jpeg_scan_info *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				nscans * SIZEOF(jpeg_scan_info));

+  cinfo->scan_info = scanptr;

+  cinfo->num_scans = nscans;

+

+  if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {

+    /* Custom script for YCbCr color images. */

+    /* Initial DC scan */

+    scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);

+    /* Initial AC scan: get some luma data out in a hurry */

+    scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);

+    /* Chroma data is too small to be worth expending many scans on */

+    scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);

+    scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);

+    /* Complete spectral selection for luma AC */

+    scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);

+    /* Refine next bit of luma AC */

+    scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);

+    /* Finish DC successive approximation */

+    scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);

+    /* Finish AC successive approximation */

+    scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);

+    scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);

+    /* Luma bottom bit comes last since it's usually largest scan */

+    scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);

+  } else {

+    /* All-purpose script for other color spaces. */

+    /* Successive approximation first pass */

+    scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);

+    scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);

+    scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);

+    /* Successive approximation second pass */

+    scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);

+    /* Successive approximation final pass */

+    scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);

+    scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);

+  }

+}

+

+#endif /* C_PROGRESSIVE_SUPPORTED */

diff --git a/code/jpeg-6/jcphuff.c b/code/jpeg-6/jcphuff.c
new file mode 100755
index 0000000..8d817e4
--- /dev/null
+++ b/code/jpeg-6/jcphuff.c
@@ -0,0 +1,829 @@
+/*

+ * jcphuff.c

+ *

+ * Copyright (C) 1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains Huffman entropy encoding routines for progressive JPEG.

+ *

+ * We do not support output suspension in this module, since the library

+ * currently does not allow multiple-scan files to be written with output

+ * suspension.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jchuff.h"		/* Declarations shared with jchuff.c */

+

+#ifdef C_PROGRESSIVE_SUPPORTED

+

+/* Expanded entropy encoder object for progressive Huffman encoding. */

+

+typedef struct {

+  struct jpeg_entropy_encoder pub; /* public fields */

+

+  /* Mode flag: TRUE for optimization, FALSE for actual data output */

+  boolean gather_statistics;

+

+  /* Bit-level coding status.

+   * next_output_byte/free_in_buffer are local copies of cinfo->dest fields.

+   */

+  JOCTET * next_output_byte;	/* => next byte to write in buffer */

+  size_t free_in_buffer;	/* # of byte spaces remaining in buffer */

+  INT32 put_buffer;		/* current bit-accumulation buffer */

+  int put_bits;			/* # of bits now in it */

+  j_compress_ptr cinfo;		/* link to cinfo (needed for dump_buffer) */

+

+  /* Coding status for DC components */

+  int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */

+

+  /* Coding status for AC components */

+  int ac_tbl_no;		/* the table number of the single component */

+  unsigned int EOBRUN;		/* run length of EOBs */

+  unsigned int BE;		/* # of buffered correction bits before MCU */

+  char * bit_buffer;		/* buffer for correction bits (1 per char) */

+  /* packing correction bits tightly would save some space but cost time... */

+

+  unsigned int restarts_to_go;	/* MCUs left in this restart interval */

+  int next_restart_num;		/* next restart number to write (0-7) */

+

+  /* Pointers to derived tables (these workspaces have image lifespan).

+   * Since any one scan codes only DC or only AC, we only need one set

+   * of tables, not one for DC and one for AC.

+   */

+  c_derived_tbl * derived_tbls[NUM_HUFF_TBLS];

+

+  /* Statistics tables for optimization; again, one set is enough */

+  long * count_ptrs[NUM_HUFF_TBLS];

+} phuff_entropy_encoder;

+

+typedef phuff_entropy_encoder * phuff_entropy_ptr;

+

+/* MAX_CORR_BITS is the number of bits the AC refinement correction-bit

+ * buffer can hold.  Larger sizes may slightly improve compression, but

+ * 1000 is already well into the realm of overkill.

+ * The minimum safe size is 64 bits.

+ */

+

+#define MAX_CORR_BITS  1000	/* Max # of correction bits I can buffer */

+

+/* IRIGHT_SHIFT is like RIGHT_SHIFT, but works on int rather than INT32.

+ * We assume that int right shift is unsigned if INT32 right shift is,

+ * which should be safe.

+ */

+

+#ifdef RIGHT_SHIFT_IS_UNSIGNED

+#define ISHIFT_TEMPS	int ishift_temp;

+#define IRIGHT_SHIFT(x,shft)  \

+	((ishift_temp = (x)) < 0 ? \

+	 (ishift_temp >> (shft)) | ((~0) << (16-(shft))) : \

+	 (ishift_temp >> (shft)))

+#else

+#define ISHIFT_TEMPS

+#define IRIGHT_SHIFT(x,shft)	((x) >> (shft))

+#endif

+

+/* Forward declarations */

+METHODDEF boolean encode_mcu_DC_first JPP((j_compress_ptr cinfo,

+					   JBLOCKROW *MCU_data));

+METHODDEF boolean encode_mcu_AC_first JPP((j_compress_ptr cinfo,

+					   JBLOCKROW *MCU_data));

+METHODDEF boolean encode_mcu_DC_refine JPP((j_compress_ptr cinfo,

+					    JBLOCKROW *MCU_data));

+METHODDEF boolean encode_mcu_AC_refine JPP((j_compress_ptr cinfo,

+					    JBLOCKROW *MCU_data));

+METHODDEF void finish_pass_phuff JPP((j_compress_ptr cinfo));

+METHODDEF void finish_pass_gather_phuff JPP((j_compress_ptr cinfo));

+

+

+/*

+ * Initialize for a Huffman-compressed scan using progressive JPEG.

+ */

+

+METHODDEF void

+start_pass_phuff (j_compress_ptr cinfo, boolean gather_statistics)

+{  

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  boolean is_DC_band;

+  int ci, tbl;

+  jpeg_component_info * compptr;

+

+  entropy->cinfo = cinfo;

+  entropy->gather_statistics = gather_statistics;

+

+  is_DC_band = (cinfo->Ss == 0);

+

+  /* We assume jcmaster.c already validated the scan parameters. */

+

+  /* Select execution routines */

+  if (cinfo->Ah == 0) {

+    if (is_DC_band)

+      entropy->pub.encode_mcu = encode_mcu_DC_first;

+    else

+      entropy->pub.encode_mcu = encode_mcu_AC_first;

+  } else {

+    if (is_DC_band)

+      entropy->pub.encode_mcu = encode_mcu_DC_refine;

+    else {

+      entropy->pub.encode_mcu = encode_mcu_AC_refine;

+      /* AC refinement needs a correction bit buffer */

+      if (entropy->bit_buffer == NULL)

+	entropy->bit_buffer = (char *)

+	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				      MAX_CORR_BITS * SIZEOF(char));

+    }

+  }

+  if (gather_statistics)

+    entropy->pub.finish_pass = finish_pass_gather_phuff;

+  else

+    entropy->pub.finish_pass = finish_pass_phuff;

+

+  /* Only DC coefficients may be interleaved, so cinfo->comps_in_scan = 1

+   * for AC coefficients.

+   */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    /* Initialize DC predictions to 0 */

+    entropy->last_dc_val[ci] = 0;

+    /* Make sure requested tables are present */

+    /* (In gather mode, tables need not be allocated yet) */

+    if (is_DC_band) {

+      if (cinfo->Ah != 0)	/* DC refinement needs no table */

+	continue;

+      tbl = compptr->dc_tbl_no;

+      if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||

+	  (cinfo->dc_huff_tbl_ptrs[tbl] == NULL && !gather_statistics))

+	ERREXIT1(cinfo,JERR_NO_HUFF_TABLE, tbl);

+    } else {

+      entropy->ac_tbl_no = tbl = compptr->ac_tbl_no;

+      if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||

+          (cinfo->ac_huff_tbl_ptrs[tbl] == NULL && !gather_statistics))

+        ERREXIT1(cinfo,JERR_NO_HUFF_TABLE, tbl);

+    }

+    if (gather_statistics) {

+      /* Allocate and zero the statistics tables */

+      /* Note that jpeg_gen_optimal_table expects 257 entries in each table! */

+      if (entropy->count_ptrs[tbl] == NULL)

+	entropy->count_ptrs[tbl] = (long *)

+	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				      257 * SIZEOF(long));

+      MEMZERO(entropy->count_ptrs[tbl], 257 * SIZEOF(long));

+    } else {

+      /* Compute derived values for Huffman tables */

+      /* We may do this more than once for a table, but it's not expensive */

+      if (is_DC_band)

+        jpeg_make_c_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[tbl],

+				& entropy->derived_tbls[tbl]);

+      else

+        jpeg_make_c_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[tbl],

+				& entropy->derived_tbls[tbl]);

+    }

+  }

+

+  /* Initialize AC stuff */

+  entropy->EOBRUN = 0;

+  entropy->BE = 0;

+

+  /* Initialize bit buffer to empty */

+  entropy->put_buffer = 0;

+  entropy->put_bits = 0;

+

+  /* Initialize restart stuff */

+  entropy->restarts_to_go = cinfo->restart_interval;

+  entropy->next_restart_num = 0;

+}

+

+

+/* Outputting bytes to the file.

+ * NB: these must be called only when actually outputting,

+ * that is, entropy->gather_statistics == FALSE.

+ */

+

+/* Emit a byte */

+#define emit_byte(entropy,val)  \

+	{ *(entropy)->next_output_byte++ = (JOCTET) (val);  \

+	  if (--(entropy)->free_in_buffer == 0)  \

+	    dump_buffer(entropy); }

+

+

+LOCAL void

+dump_buffer (phuff_entropy_ptr entropy)

+/* Empty the output buffer; we do not support suspension in this module. */

+{

+  struct jpeg_destination_mgr * dest = entropy->cinfo->dest;

+

+  if (! (*dest->empty_output_buffer) (entropy->cinfo))

+    ERREXIT(entropy->cinfo, JERR_CANT_SUSPEND);

+  /* After a successful buffer dump, must reset buffer pointers */

+  entropy->next_output_byte = dest->next_output_byte;

+  entropy->free_in_buffer = dest->free_in_buffer;

+}

+

+

+/* Outputting bits to the file */

+

+/* Only the right 24 bits of put_buffer are used; the valid bits are

+ * left-justified in this part.  At most 16 bits can be passed to emit_bits

+ * in one call, and we never retain more than 7 bits in put_buffer

+ * between calls, so 24 bits are sufficient.

+ */

+

+INLINE

+LOCAL void

+emit_bits (phuff_entropy_ptr entropy, unsigned int code, int size)

+/* Emit some bits, unless we are in gather mode */

+{

+  /* This routine is heavily used, so it's worth coding tightly. */

+  register INT32 put_buffer = (INT32) code;

+  register int put_bits = entropy->put_bits;

+

+  /* if size is 0, caller used an invalid Huffman table entry */

+  if (size == 0)

+    ERREXIT(entropy->cinfo, JERR_HUFF_MISSING_CODE);

+

+  if (entropy->gather_statistics)

+    return;			/* do nothing if we're only getting stats */

+

+  put_buffer &= (((INT32) 1)<<size) - 1; /* mask off any extra bits in code */

+  

+  put_bits += size;		/* new number of bits in buffer */

+  

+  put_buffer <<= 24 - put_bits; /* align incoming bits */

+

+  put_buffer |= entropy->put_buffer; /* and merge with old buffer contents */

+

+  while (put_bits >= 8) {

+    int c = (int) ((put_buffer >> 16) & 0xFF);

+    

+    emit_byte(entropy, c);

+    if (c == 0xFF) {		/* need to stuff a zero byte? */

+      emit_byte(entropy, 0);

+    }

+    put_buffer <<= 8;

+    put_bits -= 8;

+  }

+

+  entropy->put_buffer = put_buffer; /* update variables */

+  entropy->put_bits = put_bits;

+}

+

+

+LOCAL void

+flush_bits (phuff_entropy_ptr entropy)

+{

+  emit_bits(entropy, 0x7F, 7); /* fill any partial byte with ones */

+  entropy->put_buffer = 0;     /* and reset bit-buffer to empty */

+  entropy->put_bits = 0;

+}

+

+

+/*

+ * Emit (or just count) a Huffman symbol.

+ */

+

+INLINE

+LOCAL void

+emit_symbol (phuff_entropy_ptr entropy, int tbl_no, int symbol)

+{

+  if (entropy->gather_statistics)

+    entropy->count_ptrs[tbl_no][symbol]++;

+  else {

+    c_derived_tbl * tbl = entropy->derived_tbls[tbl_no];

+    emit_bits(entropy, tbl->ehufco[symbol], tbl->ehufsi[symbol]);

+  }

+}

+

+

+/*

+ * Emit bits from a correction bit buffer.

+ */

+

+LOCAL void

+emit_buffered_bits (phuff_entropy_ptr entropy, char * bufstart,

+		    unsigned int nbits)

+{

+  if (entropy->gather_statistics)

+    return;			/* no real work */

+

+  while (nbits > 0) {

+    emit_bits(entropy, (unsigned int) (*bufstart), 1);

+    bufstart++;

+    nbits--;

+  }

+}

+

+

+/*

+ * Emit any pending EOBRUN symbol.

+ */

+

+LOCAL void

+emit_eobrun (phuff_entropy_ptr entropy)

+{

+  register int temp, nbits;

+

+  if (entropy->EOBRUN > 0) {	/* if there is any pending EOBRUN */

+    temp = entropy->EOBRUN;

+    nbits = 0;

+    while ((temp >>= 1))

+      nbits++;

+

+    emit_symbol(entropy, entropy->ac_tbl_no, nbits << 4);

+    if (nbits)

+      emit_bits(entropy, entropy->EOBRUN, nbits);

+

+    entropy->EOBRUN = 0;

+

+    /* Emit any buffered correction bits */

+    emit_buffered_bits(entropy, entropy->bit_buffer, entropy->BE);

+    entropy->BE = 0;

+  }

+}

+

+

+/*

+ * Emit a restart marker & resynchronize predictions.

+ */

+

+LOCAL void

+emit_restart (phuff_entropy_ptr entropy, int restart_num)

+{

+  int ci;

+

+  emit_eobrun(entropy);

+

+  if (! entropy->gather_statistics) {

+    flush_bits(entropy);

+    emit_byte(entropy, 0xFF);

+    emit_byte(entropy, JPEG_RST0 + restart_num);

+  }

+

+  if (entropy->cinfo->Ss == 0) {

+    /* Re-initialize DC predictions to 0 */

+    for (ci = 0; ci < entropy->cinfo->comps_in_scan; ci++)

+      entropy->last_dc_val[ci] = 0;

+  } else {

+    /* Re-initialize all AC-related fields to 0 */

+    entropy->EOBRUN = 0;

+    entropy->BE = 0;

+  }

+}

+

+

+/*

+ * MCU encoding for DC initial scan (either spectral selection,

+ * or first pass of successive approximation).

+ */

+

+METHODDEF boolean

+encode_mcu_DC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  register int temp, temp2;

+  register int nbits;

+  int blkn, ci;

+  int Al = cinfo->Al;

+  JBLOCKROW block;

+  jpeg_component_info * compptr;

+  ISHIFT_TEMPS

+

+  entropy->next_output_byte = cinfo->dest->next_output_byte;

+  entropy->free_in_buffer = cinfo->dest->free_in_buffer;

+

+  /* Emit restart marker if needed */

+  if (cinfo->restart_interval)

+    if (entropy->restarts_to_go == 0)

+      emit_restart(entropy, entropy->next_restart_num);

+

+  /* Encode the MCU data blocks */

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    block = MCU_data[blkn];

+    ci = cinfo->MCU_membership[blkn];

+    compptr = cinfo->cur_comp_info[ci];

+

+    /* Compute the DC value after the required point transform by Al.

+     * This is simply an arithmetic right shift.

+     */

+    temp2 = IRIGHT_SHIFT((int) ((*block)[0]), Al);

+

+    /* DC differences are figured on the point-transformed values. */

+    temp = temp2 - entropy->last_dc_val[ci];

+    entropy->last_dc_val[ci] = temp2;

+

+    /* Encode the DC coefficient difference per section G.1.2.1 */

+    temp2 = temp;

+    if (temp < 0) {

+      temp = -temp;		/* temp is abs value of input */

+      /* For a negative input, want temp2 = bitwise complement of abs(input) */

+      /* This code assumes we are on a two's complement machine */

+      temp2--;

+    }

+    

+    /* Find the number of bits needed for the magnitude of the coefficient */

+    nbits = 0;

+    while (temp) {

+      nbits++;

+      temp >>= 1;

+    }

+    

+    /* Count/emit the Huffman-coded symbol for the number of bits */

+    emit_symbol(entropy, compptr->dc_tbl_no, nbits);

+    

+    /* Emit that number of bits of the value, if positive, */

+    /* or the complement of its magnitude, if negative. */

+    if (nbits)			/* emit_bits rejects calls with size 0 */

+      emit_bits(entropy, (unsigned int) temp2, nbits);

+  }

+

+  cinfo->dest->next_output_byte = entropy->next_output_byte;

+  cinfo->dest->free_in_buffer = entropy->free_in_buffer;

+

+  /* Update restart-interval state too */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      entropy->restarts_to_go = cinfo->restart_interval;

+      entropy->next_restart_num++;

+      entropy->next_restart_num &= 7;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * MCU encoding for AC initial scan (either spectral selection,

+ * or first pass of successive approximation).

+ */

+

+METHODDEF boolean

+encode_mcu_AC_first (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  register int temp, temp2;

+  register int nbits;

+  register int r, k;

+  int Se = cinfo->Se;

+  int Al = cinfo->Al;

+  JBLOCKROW block;

+

+  entropy->next_output_byte = cinfo->dest->next_output_byte;

+  entropy->free_in_buffer = cinfo->dest->free_in_buffer;

+

+  /* Emit restart marker if needed */

+  if (cinfo->restart_interval)

+    if (entropy->restarts_to_go == 0)

+      emit_restart(entropy, entropy->next_restart_num);

+

+  /* Encode the MCU data block */

+  block = MCU_data[0];

+

+  /* Encode the AC coefficients per section G.1.2.2, fig. G.3 */

+  

+  r = 0;			/* r = run length of zeros */

+   

+  for (k = cinfo->Ss; k <= Se; k++) {

+    if ((temp = (*block)[jpeg_natural_order[k]]) == 0) {

+      r++;

+      continue;

+    }

+    /* We must apply the point transform by Al.  For AC coefficients this

+     * is an integer division with rounding towards 0.  To do this portably

+     * in C, we shift after obtaining the absolute value; so the code is

+     * interwoven with finding the abs value (temp) and output bits (temp2).

+     */

+    if (temp < 0) {

+      temp = -temp;		/* temp is abs value of input */

+      temp >>= Al;		/* apply the point transform */

+      /* For a negative coef, want temp2 = bitwise complement of abs(coef) */

+      temp2 = ~temp;

+    } else {

+      temp >>= Al;		/* apply the point transform */

+      temp2 = temp;

+    }

+    /* Watch out for case that nonzero coef is zero after point transform */

+    if (temp == 0) {

+      r++;

+      continue;

+    }

+

+    /* Emit any pending EOBRUN */

+    if (entropy->EOBRUN > 0)

+      emit_eobrun(entropy);

+    /* if run length > 15, must emit special run-length-16 codes (0xF0) */

+    while (r > 15) {

+      emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);

+      r -= 16;

+    }

+

+    /* Find the number of bits needed for the magnitude of the coefficient */

+    nbits = 1;			/* there must be at least one 1 bit */

+    while ((temp >>= 1))

+      nbits++;

+

+    /* Count/emit Huffman symbol for run length / number of bits */

+    emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + nbits);

+

+    /* Emit that number of bits of the value, if positive, */

+    /* or the complement of its magnitude, if negative. */

+    emit_bits(entropy, (unsigned int) temp2, nbits);

+

+    r = 0;			/* reset zero run length */

+  }

+

+  if (r > 0) {			/* If there are trailing zeroes, */

+    entropy->EOBRUN++;		/* count an EOB */

+    if (entropy->EOBRUN == 0x7FFF)

+      emit_eobrun(entropy);	/* force it out to avoid overflow */

+  }

+

+  cinfo->dest->next_output_byte = entropy->next_output_byte;

+  cinfo->dest->free_in_buffer = entropy->free_in_buffer;

+

+  /* Update restart-interval state too */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      entropy->restarts_to_go = cinfo->restart_interval;

+      entropy->next_restart_num++;

+      entropy->next_restart_num &= 7;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * MCU encoding for DC successive approximation refinement scan.

+ * Note: we assume such scans can be multi-component, although the spec

+ * is not very clear on the point.

+ */

+

+METHODDEF boolean

+encode_mcu_DC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  register int temp;

+  int blkn;

+  int Al = cinfo->Al;

+  JBLOCKROW block;

+

+  entropy->next_output_byte = cinfo->dest->next_output_byte;

+  entropy->free_in_buffer = cinfo->dest->free_in_buffer;

+

+  /* Emit restart marker if needed */

+  if (cinfo->restart_interval)

+    if (entropy->restarts_to_go == 0)

+      emit_restart(entropy, entropy->next_restart_num);

+

+  /* Encode the MCU data blocks */

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    block = MCU_data[blkn];

+

+    /* We simply emit the Al'th bit of the DC coefficient value. */

+    temp = (*block)[0];

+    emit_bits(entropy, (unsigned int) (temp >> Al), 1);

+  }

+

+  cinfo->dest->next_output_byte = entropy->next_output_byte;

+  cinfo->dest->free_in_buffer = entropy->free_in_buffer;

+

+  /* Update restart-interval state too */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      entropy->restarts_to_go = cinfo->restart_interval;

+      entropy->next_restart_num++;

+      entropy->next_restart_num &= 7;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * MCU encoding for AC successive approximation refinement scan.

+ */

+

+METHODDEF boolean

+encode_mcu_AC_refine (j_compress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  register int temp;

+  register int r, k;

+  int EOB;

+  char *BR_buffer;

+  unsigned int BR;

+  int Se = cinfo->Se;

+  int Al = cinfo->Al;

+  JBLOCKROW block;

+  int absvalues[DCTSIZE2];

+

+  entropy->next_output_byte = cinfo->dest->next_output_byte;

+  entropy->free_in_buffer = cinfo->dest->free_in_buffer;

+

+  /* Emit restart marker if needed */

+  if (cinfo->restart_interval)

+    if (entropy->restarts_to_go == 0)

+      emit_restart(entropy, entropy->next_restart_num);

+

+  /* Encode the MCU data block */

+  block = MCU_data[0];

+

+  /* It is convenient to make a pre-pass to determine the transformed

+   * coefficients' absolute values and the EOB position.

+   */

+  EOB = 0;

+  for (k = cinfo->Ss; k <= Se; k++) {

+    temp = (*block)[jpeg_natural_order[k]];

+    /* We must apply the point transform by Al.  For AC coefficients this

+     * is an integer division with rounding towards 0.  To do this portably

+     * in C, we shift after obtaining the absolute value.

+     */

+    if (temp < 0)

+      temp = -temp;		/* temp is abs value of input */

+    temp >>= Al;		/* apply the point transform */

+    absvalues[k] = temp;	/* save abs value for main pass */

+    if (temp == 1)

+      EOB = k;			/* EOB = index of last newly-nonzero coef */

+  }

+

+  /* Encode the AC coefficients per section G.1.2.3, fig. G.7 */

+  

+  r = 0;			/* r = run length of zeros */

+  BR = 0;			/* BR = count of buffered bits added now */

+  BR_buffer = entropy->bit_buffer + entropy->BE; /* Append bits to buffer */

+

+  for (k = cinfo->Ss; k <= Se; k++) {

+    if ((temp = absvalues[k]) == 0) {

+      r++;

+      continue;

+    }

+

+    /* Emit any required ZRLs, but not if they can be folded into EOB */

+    while (r > 15 && k <= EOB) {

+      /* emit any pending EOBRUN and the BE correction bits */

+      emit_eobrun(entropy);

+      /* Emit ZRL */

+      emit_symbol(entropy, entropy->ac_tbl_no, 0xF0);

+      r -= 16;

+      /* Emit buffered correction bits that must be associated with ZRL */

+      emit_buffered_bits(entropy, BR_buffer, BR);

+      BR_buffer = entropy->bit_buffer; /* BE bits are gone now */

+      BR = 0;

+    }

+

+    /* If the coef was previously nonzero, it only needs a correction bit.

+     * NOTE: a straight translation of the spec's figure G.7 would suggest

+     * that we also need to test r > 15.  But if r > 15, we can only get here

+     * if k > EOB, which implies that this coefficient is not 1.

+     */

+    if (temp > 1) {

+      /* The correction bit is the next bit of the absolute value. */

+      BR_buffer[BR++] = (char) (temp & 1);

+      continue;

+    }

+

+    /* Emit any pending EOBRUN and the BE correction bits */

+    emit_eobrun(entropy);

+

+    /* Count/emit Huffman symbol for run length / number of bits */

+    emit_symbol(entropy, entropy->ac_tbl_no, (r << 4) + 1);

+

+    /* Emit output bit for newly-nonzero coef */

+    temp = ((*block)[jpeg_natural_order[k]] < 0) ? 0 : 1;

+    emit_bits(entropy, (unsigned int) temp, 1);

+

+    /* Emit buffered correction bits that must be associated with this code */

+    emit_buffered_bits(entropy, BR_buffer, BR);

+    BR_buffer = entropy->bit_buffer; /* BE bits are gone now */

+    BR = 0;

+    r = 0;			/* reset zero run length */

+  }

+

+  if (r > 0 || BR > 0) {	/* If there are trailing zeroes, */

+    entropy->EOBRUN++;		/* count an EOB */

+    entropy->BE += BR;		/* concat my correction bits to older ones */

+    /* We force out the EOB if we risk either:

+     * 1. overflow of the EOB counter;

+     * 2. overflow of the correction bit buffer during the next MCU.

+     */

+    if (entropy->EOBRUN == 0x7FFF || entropy->BE > (MAX_CORR_BITS-DCTSIZE2+1))

+      emit_eobrun(entropy);

+  }

+

+  cinfo->dest->next_output_byte = entropy->next_output_byte;

+  cinfo->dest->free_in_buffer = entropy->free_in_buffer;

+

+  /* Update restart-interval state too */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0) {

+      entropy->restarts_to_go = cinfo->restart_interval;

+      entropy->next_restart_num++;

+      entropy->next_restart_num &= 7;

+    }

+    entropy->restarts_to_go--;

+  }

+

+  return TRUE;

+}

+

+

+/*

+ * Finish up at the end of a Huffman-compressed progressive scan.

+ */

+

+METHODDEF void

+finish_pass_phuff (j_compress_ptr cinfo)

+{   

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+

+  entropy->next_output_byte = cinfo->dest->next_output_byte;

+  entropy->free_in_buffer = cinfo->dest->free_in_buffer;

+

+  /* Flush out any buffered data */

+  emit_eobrun(entropy);

+  flush_bits(entropy);

+

+  cinfo->dest->next_output_byte = entropy->next_output_byte;

+  cinfo->dest->free_in_buffer = entropy->free_in_buffer;

+}

+

+

+/*

+ * Finish up a statistics-gathering pass and create the new Huffman tables.

+ */

+

+METHODDEF void

+finish_pass_gather_phuff (j_compress_ptr cinfo)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  boolean is_DC_band;

+  int ci, tbl;

+  jpeg_component_info * compptr;

+  JHUFF_TBL **htblptr;

+  boolean did[NUM_HUFF_TBLS];

+

+  /* Flush out buffered data (all we care about is counting the EOB symbol) */

+  emit_eobrun(entropy);

+

+  is_DC_band = (cinfo->Ss == 0);

+

+  /* It's important not to apply jpeg_gen_optimal_table more than once

+   * per table, because it clobbers the input frequency counts!

+   */

+  MEMZERO(did, SIZEOF(did));

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    if (is_DC_band) {

+      if (cinfo->Ah != 0)	/* DC refinement needs no table */

+	continue;

+      tbl = compptr->dc_tbl_no;

+    } else {

+      tbl = compptr->ac_tbl_no;

+    }

+    if (! did[tbl]) {

+      if (is_DC_band)

+        htblptr = & cinfo->dc_huff_tbl_ptrs[tbl];

+      else

+        htblptr = & cinfo->ac_huff_tbl_ptrs[tbl];

+      if (*htblptr == NULL)

+        *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);

+      jpeg_gen_optimal_table(cinfo, *htblptr, entropy->count_ptrs[tbl]);

+      did[tbl] = TRUE;

+    }

+  }

+}

+

+

+/*

+ * Module initialization routine for progressive Huffman entropy encoding.

+ */

+

+GLOBAL void

+jinit_phuff_encoder (j_compress_ptr cinfo)

+{

+  phuff_entropy_ptr entropy;

+  int i;

+

+  entropy = (phuff_entropy_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(phuff_entropy_encoder));

+  cinfo->entropy = (struct jpeg_entropy_encoder *) entropy;

+  entropy->pub.start_pass = start_pass_phuff;

+

+  /* Mark tables unallocated */

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    entropy->derived_tbls[i] = NULL;

+    entropy->count_ptrs[i] = NULL;

+  }

+  entropy->bit_buffer = NULL;	/* needed only in AC refinement scan */

+}

+

+#endif /* C_PROGRESSIVE_SUPPORTED */

diff --git a/code/jpeg-6/jcprepct.c b/code/jpeg-6/jcprepct.c
new file mode 100755
index 0000000..d6567fb
--- /dev/null
+++ b/code/jpeg-6/jcprepct.c
@@ -0,0 +1,371 @@
+/*

+ * jcprepct.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the compression preprocessing controller.

+ * This controller manages the color conversion, downsampling,

+ * and edge expansion steps.

+ *

+ * Most of the complexity here is associated with buffering input rows

+ * as required by the downsampler.  See the comments at the head of

+ * jcsample.c for the downsampler's needs.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* At present, jcsample.c can request context rows only for smoothing.

+ * In the future, we might also need context rows for CCIR601 sampling

+ * or other more-complex downsampling procedures.  The code to support

+ * context rows should be compiled only if needed.

+ */

+#ifdef INPUT_SMOOTHING_SUPPORTED

+#define CONTEXT_ROWS_SUPPORTED

+#endif

+

+

+/*

+ * For the simple (no-context-row) case, we just need to buffer one

+ * row group's worth of pixels for the downsampling step.  At the bottom of

+ * the image, we pad to a full row group by replicating the last pixel row.

+ * The downsampler's last output row is then replicated if needed to pad

+ * out to a full iMCU row.

+ *

+ * When providing context rows, we must buffer three row groups' worth of

+ * pixels.  Three row groups are physically allocated, but the row pointer

+ * arrays are made five row groups high, with the extra pointers above and

+ * below "wrapping around" to point to the last and first real row groups.

+ * This allows the downsampler to access the proper context rows.

+ * At the top and bottom of the image, we create dummy context rows by

+ * copying the first or last real pixel row.  This copying could be avoided

+ * by pointer hacking as is done in jdmainct.c, but it doesn't seem worth the

+ * trouble on the compression side.

+ */

+

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_c_prep_controller pub; /* public fields */

+

+  /* Downsampling input buffer.  This buffer holds color-converted data

+   * until we have enough to do a downsample step.

+   */

+  JSAMPARRAY color_buf[MAX_COMPONENTS];

+

+  JDIMENSION rows_to_go;	/* counts rows remaining in source image */

+  int next_buf_row;		/* index of next row to store in color_buf */

+

+#ifdef CONTEXT_ROWS_SUPPORTED	/* only needed for context case */

+  int this_row_group;		/* starting row index of group to process */

+  int next_buf_stop;		/* downsample when we reach this index */

+#endif

+} my_prep_controller;

+

+typedef my_prep_controller * my_prep_ptr;

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_prep (j_compress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;

+

+  if (pass_mode != JBUF_PASS_THRU)

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+

+  /* Initialize total-height counter for detecting bottom of image */

+  prep->rows_to_go = cinfo->image_height;

+  /* Mark the conversion buffer empty */

+  prep->next_buf_row = 0;

+#ifdef CONTEXT_ROWS_SUPPORTED

+  /* Preset additional state variables for context mode.

+   * These aren't used in non-context mode, so we needn't test which mode.

+   */

+  prep->this_row_group = 0;

+  /* Set next_buf_stop to stop after two row groups have been read in. */

+  prep->next_buf_stop = 2 * cinfo->max_v_samp_factor;

+#endif

+}

+

+

+/*

+ * Expand an image vertically from height input_rows to height output_rows,

+ * by duplicating the bottom row.

+ */

+

+LOCAL void

+expand_bottom_edge (JSAMPARRAY image_data, JDIMENSION num_cols,

+		    int input_rows, int output_rows)

+{

+  register int row;

+

+  for (row = input_rows; row < output_rows; row++) {

+    jcopy_sample_rows(image_data, input_rows-1, image_data, row,

+		      1, num_cols);

+  }

+}

+

+

+/*

+ * Process some data in the simple no-context case.

+ *

+ * Preprocessor output data is counted in "row groups".  A row group

+ * is defined to be v_samp_factor sample rows of each component.

+ * Downsampling will produce this much data from each max_v_samp_factor

+ * input rows.

+ */

+

+METHODDEF void

+pre_process_data (j_compress_ptr cinfo,

+		  JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,

+		  JDIMENSION in_rows_avail,

+		  JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,

+		  JDIMENSION out_row_groups_avail)

+{

+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;

+  int numrows, ci;

+  JDIMENSION inrows;

+  jpeg_component_info * compptr;

+

+  while (*in_row_ctr < in_rows_avail &&

+	 *out_row_group_ctr < out_row_groups_avail) {

+    /* Do color conversion to fill the conversion buffer. */

+    inrows = in_rows_avail - *in_row_ctr;

+    numrows = cinfo->max_v_samp_factor - prep->next_buf_row;

+    numrows = (int) MIN((JDIMENSION) numrows, inrows);

+    (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,

+				       prep->color_buf,

+				       (JDIMENSION) prep->next_buf_row,

+				       numrows);

+    *in_row_ctr += numrows;

+    prep->next_buf_row += numrows;

+    prep->rows_to_go -= numrows;

+    /* If at bottom of image, pad to fill the conversion buffer. */

+    if (prep->rows_to_go == 0 &&

+	prep->next_buf_row < cinfo->max_v_samp_factor) {

+      for (ci = 0; ci < cinfo->num_components; ci++) {

+	expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,

+			   prep->next_buf_row, cinfo->max_v_samp_factor);

+      }

+      prep->next_buf_row = cinfo->max_v_samp_factor;

+    }

+    /* If we've filled the conversion buffer, empty it. */

+    if (prep->next_buf_row == cinfo->max_v_samp_factor) {

+      (*cinfo->downsample->downsample) (cinfo,

+					prep->color_buf, (JDIMENSION) 0,

+					output_buf, *out_row_group_ctr);

+      prep->next_buf_row = 0;

+      (*out_row_group_ctr)++;

+    }

+    /* If at bottom of image, pad the output to a full iMCU height.

+     * Note we assume the caller is providing a one-iMCU-height output buffer!

+     */

+    if (prep->rows_to_go == 0 &&

+	*out_row_group_ctr < out_row_groups_avail) {

+      for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	   ci++, compptr++) {

+	expand_bottom_edge(output_buf[ci],

+			   compptr->width_in_blocks * DCTSIZE,

+			   (int) (*out_row_group_ctr * compptr->v_samp_factor),

+			   (int) (out_row_groups_avail * compptr->v_samp_factor));

+      }

+      *out_row_group_ctr = out_row_groups_avail;

+      break;			/* can exit outer loop without test */

+    }

+  }

+}

+

+

+#ifdef CONTEXT_ROWS_SUPPORTED

+

+/*

+ * Process some data in the context case.

+ */

+

+METHODDEF void

+pre_process_context (j_compress_ptr cinfo,

+		     JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,

+		     JDIMENSION in_rows_avail,

+		     JSAMPIMAGE output_buf, JDIMENSION *out_row_group_ctr,

+		     JDIMENSION out_row_groups_avail)

+{

+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;

+  int numrows, ci;

+  int buf_height = cinfo->max_v_samp_factor * 3;

+  JDIMENSION inrows;

+  jpeg_component_info * compptr;

+

+  while (*out_row_group_ctr < out_row_groups_avail) {

+    if (*in_row_ctr < in_rows_avail) {

+      /* Do color conversion to fill the conversion buffer. */

+      inrows = in_rows_avail - *in_row_ctr;

+      numrows = prep->next_buf_stop - prep->next_buf_row;

+      numrows = (int) MIN((JDIMENSION) numrows, inrows);

+      (*cinfo->cconvert->color_convert) (cinfo, input_buf + *in_row_ctr,

+					 prep->color_buf,

+					 (JDIMENSION) prep->next_buf_row,

+					 numrows);

+      /* Pad at top of image, if first time through */

+      if (prep->rows_to_go == cinfo->image_height) {

+	for (ci = 0; ci < cinfo->num_components; ci++) {

+	  int row;

+	  for (row = 1; row <= cinfo->max_v_samp_factor; row++) {

+	    jcopy_sample_rows(prep->color_buf[ci], 0,

+			      prep->color_buf[ci], -row,

+			      1, cinfo->image_width);

+	  }

+	}

+      }

+      *in_row_ctr += numrows;

+      prep->next_buf_row += numrows;

+      prep->rows_to_go -= numrows;

+    } else {

+      /* Return for more data, unless we are at the bottom of the image. */

+      if (prep->rows_to_go != 0)

+	break;

+    }

+    /* If at bottom of image, pad to fill the conversion buffer. */

+    if (prep->rows_to_go == 0 &&

+	prep->next_buf_row < prep->next_buf_stop) {

+      for (ci = 0; ci < cinfo->num_components; ci++) {

+	expand_bottom_edge(prep->color_buf[ci], cinfo->image_width,

+			   prep->next_buf_row, prep->next_buf_stop);

+      }

+      prep->next_buf_row = prep->next_buf_stop;

+    }

+    /* If we've gotten enough data, downsample a row group. */

+    if (prep->next_buf_row == prep->next_buf_stop) {

+      (*cinfo->downsample->downsample) (cinfo,

+					prep->color_buf,

+					(JDIMENSION) prep->this_row_group,

+					output_buf, *out_row_group_ctr);

+      (*out_row_group_ctr)++;

+      /* Advance pointers with wraparound as necessary. */

+      prep->this_row_group += cinfo->max_v_samp_factor;

+      if (prep->this_row_group >= buf_height)

+	prep->this_row_group = 0;

+      if (prep->next_buf_row >= buf_height)

+	prep->next_buf_row = 0;

+      prep->next_buf_stop = prep->next_buf_row + cinfo->max_v_samp_factor;

+    }

+    /* If at bottom of image, pad the output to a full iMCU height.

+     * Note we assume the caller is providing a one-iMCU-height output buffer!

+     */

+    if (prep->rows_to_go == 0 &&

+	*out_row_group_ctr < out_row_groups_avail) {

+      for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	   ci++, compptr++) {

+	expand_bottom_edge(output_buf[ci],

+			   compptr->width_in_blocks * DCTSIZE,

+			   (int) (*out_row_group_ctr * compptr->v_samp_factor),

+			   (int) (out_row_groups_avail * compptr->v_samp_factor));

+      }

+      *out_row_group_ctr = out_row_groups_avail;

+      break;			/* can exit outer loop without test */

+    }

+  }

+}

+

+

+/*

+ * Create the wrapped-around downsampling input buffer needed for context mode.

+ */

+

+LOCAL void

+create_context_buffer (j_compress_ptr cinfo)

+{

+  my_prep_ptr prep = (my_prep_ptr) cinfo->prep;

+  int rgroup_height = cinfo->max_v_samp_factor;

+  int ci, i;

+  jpeg_component_info * compptr;

+  JSAMPARRAY true_buffer, fake_buffer;

+

+  /* Grab enough space for fake row pointers for all the components;

+   * we need five row groups' worth of pointers for each component.

+   */

+  fake_buffer = (JSAMPARRAY)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(cinfo->num_components * 5 * rgroup_height) *

+				SIZEOF(JSAMPROW));

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Allocate the actual buffer space (3 row groups) for this component.

+     * We make the buffer wide enough to allow the downsampler to edge-expand

+     * horizontally within the buffer, if it so chooses.

+     */

+    true_buffer = (*cinfo->mem->alloc_sarray)

+      ((j_common_ptr) cinfo, JPOOL_IMAGE,

+       (JDIMENSION) (((long) compptr->width_in_blocks * DCTSIZE *

+		      cinfo->max_h_samp_factor) / compptr->h_samp_factor),

+       (JDIMENSION) (3 * rgroup_height));

+    /* Copy true buffer row pointers into the middle of the fake row array */

+    MEMCOPY(fake_buffer + rgroup_height, true_buffer,

+	    3 * rgroup_height * SIZEOF(JSAMPROW));

+    /* Fill in the above and below wraparound pointers */

+    for (i = 0; i < rgroup_height; i++) {

+      fake_buffer[i] = true_buffer[2 * rgroup_height + i];

+      fake_buffer[4 * rgroup_height + i] = true_buffer[i];

+    }

+    prep->color_buf[ci] = fake_buffer + rgroup_height;

+    fake_buffer += 5 * rgroup_height; /* point to space for next component */

+  }

+}

+

+#endif /* CONTEXT_ROWS_SUPPORTED */

+

+

+/*

+ * Initialize preprocessing controller.

+ */

+

+GLOBAL void

+jinit_c_prep_controller (j_compress_ptr cinfo, boolean need_full_buffer)

+{

+  my_prep_ptr prep;

+  int ci;

+  jpeg_component_info * compptr;

+

+  if (need_full_buffer)		/* safety check */

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+

+  prep = (my_prep_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_prep_controller));

+  cinfo->prep = (struct jpeg_c_prep_controller *) prep;

+  prep->pub.start_pass = start_pass_prep;

+

+  /* Allocate the color conversion buffer.

+   * We make the buffer wide enough to allow the downsampler to edge-expand

+   * horizontally within the buffer, if it so chooses.

+   */

+  if (cinfo->downsample->need_context_rows) {

+    /* Set up to provide context rows */

+#ifdef CONTEXT_ROWS_SUPPORTED

+    prep->pub.pre_process_data = pre_process_context;

+    create_context_buffer(cinfo);

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+  } else {

+    /* No context, just make it tall enough for one row group */

+    prep->pub.pre_process_data = pre_process_data;

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      prep->color_buf[ci] = (*cinfo->mem->alloc_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE,

+	 (JDIMENSION) (((long) compptr->width_in_blocks * DCTSIZE *

+			cinfo->max_h_samp_factor) / compptr->h_samp_factor),

+	 (JDIMENSION) cinfo->max_v_samp_factor);

+    }

+  }

+}

diff --git a/code/jpeg-6/jcsample.c b/code/jpeg-6/jcsample.c
new file mode 100755
index 0000000..06b18f4
--- /dev/null
+++ b/code/jpeg-6/jcsample.c
@@ -0,0 +1,519 @@
+/*

+ * jcsample.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains downsampling routines.

+ *

+ * Downsampling input data is counted in "row groups".  A row group

+ * is defined to be max_v_samp_factor pixel rows of each component,

+ * from which the downsampler produces v_samp_factor sample rows.

+ * A single row group is processed in each call to the downsampler module.

+ *

+ * The downsampler is responsible for edge-expansion of its output data

+ * to fill an integral number of DCT blocks horizontally.  The source buffer

+ * may be modified if it is helpful for this purpose (the source buffer is

+ * allocated wide enough to correspond to the desired output width).

+ * The caller (the prep controller) is responsible for vertical padding.

+ *

+ * The downsampler may request "context rows" by setting need_context_rows

+ * during startup.  In this case, the input arrays will contain at least

+ * one row group's worth of pixels above and below the passed-in data;

+ * the caller will create dummy rows at image top and bottom by replicating

+ * the first or last real pixel row.

+ *

+ * An excellent reference for image resampling is

+ *   Digital Image Warping, George Wolberg, 1990.

+ *   Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.

+ *

+ * The downsampling algorithm used here is a simple average of the source

+ * pixels covered by the output pixel.  The hi-falutin sampling literature

+ * refers to this as a "box filter".  In general the characteristics of a box

+ * filter are not very good, but for the specific cases we normally use (1:1

+ * and 2:1 ratios) the box is equivalent to a "triangle filter" which is not

+ * nearly so bad.  If you intend to use other sampling ratios, you'd be well

+ * advised to improve this code.

+ *

+ * A simple input-smoothing capability is provided.  This is mainly intended

+ * for cleaning up color-dithered GIF input files (if you find it inadequate,

+ * we suggest using an external filtering program such as pnmconvol).  When

+ * enabled, each input pixel P is replaced by a weighted sum of itself and its

+ * eight neighbors.  P's weight is 1-8*SF and each neighbor's weight is SF,

+ * where SF = (smoothing_factor / 1024).

+ * Currently, smoothing is only supported for 2h2v sampling factors.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Pointer to routine to downsample a single component */

+typedef JMETHOD(void, downsample1_ptr,

+		(j_compress_ptr cinfo, jpeg_component_info * compptr,

+		 JSAMPARRAY input_data, JSAMPARRAY output_data));

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_downsampler pub;	/* public fields */

+

+  /* Downsampling method pointers, one per component */

+  downsample1_ptr methods[MAX_COMPONENTS];

+} my_downsampler;

+

+typedef my_downsampler * my_downsample_ptr;

+

+

+/*

+ * Initialize for a downsampling pass.

+ */

+

+METHODDEF void

+start_pass_downsample (j_compress_ptr cinfo)

+{

+  /* no work for now */

+}

+

+

+/*

+ * Expand a component horizontally from width input_cols to width output_cols,

+ * by duplicating the rightmost samples.

+ */

+

+LOCAL void

+expand_right_edge (JSAMPARRAY image_data, int num_rows,

+		   JDIMENSION input_cols, JDIMENSION output_cols)

+{

+  register JSAMPROW ptr;

+  register JSAMPLE pixval;

+  register int count;

+  int row;

+  int numcols = (int) (output_cols - input_cols);

+

+  if (numcols > 0) {

+    for (row = 0; row < num_rows; row++) {

+      ptr = image_data[row] + input_cols;

+      pixval = ptr[-1];		/* don't need GETJSAMPLE() here */

+      for (count = numcols; count > 0; count--)

+	*ptr++ = pixval;

+    }

+  }

+}

+

+

+/*

+ * Do downsampling for a whole row group (all components).

+ *

+ * In this version we simply downsample each component independently.

+ */

+

+METHODDEF void

+sep_downsample (j_compress_ptr cinfo,

+		JSAMPIMAGE input_buf, JDIMENSION in_row_index,

+		JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)

+{

+  my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;

+  int ci;

+  jpeg_component_info * compptr;

+  JSAMPARRAY in_ptr, out_ptr;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    in_ptr = input_buf[ci] + in_row_index;

+    out_ptr = output_buf[ci] + (out_row_group_index * compptr->v_samp_factor);

+    (*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr);

+  }

+}

+

+

+/*

+ * Downsample pixel values of a single component.

+ * One row group is processed per call.

+ * This version handles arbitrary integral sampling ratios, without smoothing.

+ * Note that this version is not actually used for customary sampling ratios.

+ */

+

+METHODDEF void

+int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,

+		JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v;

+  JDIMENSION outcol, outcol_h;	/* outcol_h == outcol*h_expand */

+  JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;

+  JSAMPROW inptr, outptr;

+  INT32 outvalue;

+

+  h_expand = cinfo->max_h_samp_factor / compptr->h_samp_factor;

+  v_expand = cinfo->max_v_samp_factor / compptr->v_samp_factor;

+  numpix = h_expand * v_expand;

+  numpix2 = numpix/2;

+

+  /* Expand input data enough to let all the output samples be generated

+   * by the standard loop.  Special-casing padded output would be more

+   * efficient.

+   */

+  expand_right_edge(input_data, cinfo->max_v_samp_factor,

+		    cinfo->image_width, output_cols * h_expand);

+

+  inrow = 0;

+  for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {

+    outptr = output_data[outrow];

+    for (outcol = 0, outcol_h = 0; outcol < output_cols;

+	 outcol++, outcol_h += h_expand) {

+      outvalue = 0;

+      for (v = 0; v < v_expand; v++) {

+	inptr = input_data[inrow+v] + outcol_h;

+	for (h = 0; h < h_expand; h++) {

+	  outvalue += (INT32) GETJSAMPLE(*inptr++);

+	}

+      }

+      *outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix);

+    }

+    inrow += v_expand;

+  }

+}

+

+

+/*

+ * Downsample pixel values of a single component.

+ * This version handles the special case of a full-size component,

+ * without smoothing.

+ */

+

+METHODDEF void

+fullsize_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,

+		     JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  /* Copy the data */

+  jcopy_sample_rows(input_data, 0, output_data, 0,

+		    cinfo->max_v_samp_factor, cinfo->image_width);

+  /* Edge-expand */

+  expand_right_edge(output_data, cinfo->max_v_samp_factor,

+		    cinfo->image_width, compptr->width_in_blocks * DCTSIZE);

+}

+

+

+/*

+ * Downsample pixel values of a single component.

+ * This version handles the common case of 2:1 horizontal and 1:1 vertical,

+ * without smoothing.

+ *

+ * A note about the "bias" calculations: when rounding fractional values to

+ * integer, we do not want to always round 0.5 up to the next integer.

+ * If we did that, we'd introduce a noticeable bias towards larger values.

+ * Instead, this code is arranged so that 0.5 will be rounded up or down at

+ * alternate pixel locations (a simple ordered dither pattern).

+ */

+

+METHODDEF void

+h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,

+		 JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  int outrow;

+  JDIMENSION outcol;

+  JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;

+  register JSAMPROW inptr, outptr;

+  register int bias;

+

+  /* Expand input data enough to let all the output samples be generated

+   * by the standard loop.  Special-casing padded output would be more

+   * efficient.

+   */

+  expand_right_edge(input_data, cinfo->max_v_samp_factor,

+		    cinfo->image_width, output_cols * 2);

+

+  for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {

+    outptr = output_data[outrow];

+    inptr = input_data[outrow];

+    bias = 0;			/* bias = 0,1,0,1,... for successive samples */

+    for (outcol = 0; outcol < output_cols; outcol++) {

+      *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1])

+			      + bias) >> 1);

+      bias ^= 1;		/* 0=>1, 1=>0 */

+      inptr += 2;

+    }

+  }

+}

+

+

+/*

+ * Downsample pixel values of a single component.

+ * This version handles the standard case of 2:1 horizontal and 2:1 vertical,

+ * without smoothing.

+ */

+

+METHODDEF void

+h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,

+		 JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  int inrow, outrow;

+  JDIMENSION outcol;

+  JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;

+  register JSAMPROW inptr0, inptr1, outptr;

+  register int bias;

+

+  /* Expand input data enough to let all the output samples be generated

+   * by the standard loop.  Special-casing padded output would be more

+   * efficient.

+   */

+  expand_right_edge(input_data, cinfo->max_v_samp_factor,

+		    cinfo->image_width, output_cols * 2);

+

+  inrow = 0;

+  for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {

+    outptr = output_data[outrow];

+    inptr0 = input_data[inrow];

+    inptr1 = input_data[inrow+1];

+    bias = 1;			/* bias = 1,2,1,2,... for successive samples */

+    for (outcol = 0; outcol < output_cols; outcol++) {

+      *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +

+			      GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1])

+			      + bias) >> 2);

+      bias ^= 3;		/* 1=>2, 2=>1 */

+      inptr0 += 2; inptr1 += 2;

+    }

+    inrow += 2;

+  }

+}

+

+

+#ifdef INPUT_SMOOTHING_SUPPORTED

+

+/*

+ * Downsample pixel values of a single component.

+ * This version handles the standard case of 2:1 horizontal and 2:1 vertical,

+ * with smoothing.  One row of context is required.

+ */

+

+METHODDEF void

+h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,

+			JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  int inrow, outrow;

+  JDIMENSION colctr;

+  JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;

+  register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr;

+  INT32 membersum, neighsum, memberscale, neighscale;

+

+  /* Expand input data enough to let all the output samples be generated

+   * by the standard loop.  Special-casing padded output would be more

+   * efficient.

+   */

+  expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,

+		    cinfo->image_width, output_cols * 2);

+

+  /* We don't bother to form the individual "smoothed" input pixel values;

+   * we can directly compute the output which is the average of the four

+   * smoothed values.  Each of the four member pixels contributes a fraction

+   * (1-8*SF) to its own smoothed image and a fraction SF to each of the three

+   * other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final

+   * output.  The four corner-adjacent neighbor pixels contribute a fraction

+   * SF to just one smoothed pixel, or SF/4 to the final output; while the

+   * eight edge-adjacent neighbors contribute SF to each of two smoothed

+   * pixels, or SF/2 overall.  In order to use integer arithmetic, these

+   * factors are scaled by 2^16 = 65536.

+   * Also recall that SF = smoothing_factor / 1024.

+   */

+

+  memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */

+  neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */

+

+  inrow = 0;

+  for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {

+    outptr = output_data[outrow];

+    inptr0 = input_data[inrow];

+    inptr1 = input_data[inrow+1];

+    above_ptr = input_data[inrow-1];

+    below_ptr = input_data[inrow+2];

+

+    /* Special case for first column: pretend column -1 is same as column 0 */

+    membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +

+		GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);

+    neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +

+	       GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +

+	       GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) +

+	       GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]);

+    neighsum += neighsum;

+    neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) +

+		GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]);

+    membersum = membersum * memberscale + neighsum * neighscale;

+    *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);

+    inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;

+

+    for (colctr = output_cols - 2; colctr > 0; colctr--) {

+      /* sum of pixels directly mapped to this output element */

+      membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +

+		  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);

+      /* sum of edge-neighbor pixels */

+      neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +

+		 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +

+		 GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) +

+		 GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]);

+      /* The edge-neighbors count twice as much as corner-neighbors */

+      neighsum += neighsum;

+      /* Add in the corner-neighbors */

+      neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) +

+		  GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]);

+      /* form final output scaled up by 2^16 */

+      membersum = membersum * memberscale + neighsum * neighscale;

+      /* round, descale and output it */

+      *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);

+      inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;

+    }

+

+    /* Special case for last column */

+    membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +

+		GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);

+    neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +

+	       GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +

+	       GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) +

+	       GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]);

+    neighsum += neighsum;

+    neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) +

+		GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]);

+    membersum = membersum * memberscale + neighsum * neighscale;

+    *outptr = (JSAMPLE) ((membersum + 32768) >> 16);

+

+    inrow += 2;

+  }

+}

+

+

+/*

+ * Downsample pixel values of a single component.

+ * This version handles the special case of a full-size component,

+ * with smoothing.  One row of context is required.

+ */

+

+METHODDEF void

+fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,

+			    JSAMPARRAY input_data, JSAMPARRAY output_data)

+{

+  int outrow;

+  JDIMENSION colctr;

+  JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;

+  register JSAMPROW inptr, above_ptr, below_ptr, outptr;

+  INT32 membersum, neighsum, memberscale, neighscale;

+  int colsum, lastcolsum, nextcolsum;

+

+  /* Expand input data enough to let all the output samples be generated

+   * by the standard loop.  Special-casing padded output would be more

+   * efficient.

+   */

+  expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,

+		    cinfo->image_width, output_cols);

+

+  /* Each of the eight neighbor pixels contributes a fraction SF to the

+   * smoothed pixel, while the main pixel contributes (1-8*SF).  In order

+   * to use integer arithmetic, these factors are multiplied by 2^16 = 65536.

+   * Also recall that SF = smoothing_factor / 1024.

+   */

+

+  memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */

+  neighscale = cinfo->smoothing_factor * 64; /* scaled SF */

+

+  for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {

+    outptr = output_data[outrow];

+    inptr = input_data[outrow];

+    above_ptr = input_data[outrow-1];

+    below_ptr = input_data[outrow+1];

+

+    /* Special case for first column */

+    colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) +

+	     GETJSAMPLE(*inptr);

+    membersum = GETJSAMPLE(*inptr++);

+    nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +

+		 GETJSAMPLE(*inptr);

+    neighsum = colsum + (colsum - membersum) + nextcolsum;

+    membersum = membersum * memberscale + neighsum * neighscale;

+    *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);

+    lastcolsum = colsum; colsum = nextcolsum;

+

+    for (colctr = output_cols - 2; colctr > 0; colctr--) {

+      membersum = GETJSAMPLE(*inptr++);

+      above_ptr++; below_ptr++;

+      nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +

+		   GETJSAMPLE(*inptr);

+      neighsum = lastcolsum + (colsum - membersum) + nextcolsum;

+      membersum = membersum * memberscale + neighsum * neighscale;

+      *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);

+      lastcolsum = colsum; colsum = nextcolsum;

+    }

+

+    /* Special case for last column */

+    membersum = GETJSAMPLE(*inptr);

+    neighsum = lastcolsum + (colsum - membersum) + colsum;

+    membersum = membersum * memberscale + neighsum * neighscale;

+    *outptr = (JSAMPLE) ((membersum + 32768) >> 16);

+

+  }

+}

+

+#endif /* INPUT_SMOOTHING_SUPPORTED */

+

+

+/*

+ * Module initialization routine for downsampling.

+ * Note that we must select a routine for each component.

+ */

+

+GLOBAL void

+jinit_downsampler (j_compress_ptr cinfo)

+{

+  my_downsample_ptr downsample;

+  int ci;

+  jpeg_component_info * compptr;

+  boolean smoothok = TRUE;

+

+  downsample = (my_downsample_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_downsampler));

+  cinfo->downsample = (struct jpeg_downsampler *) downsample;

+  downsample->pub.start_pass = start_pass_downsample;

+  downsample->pub.downsample = sep_downsample;

+  downsample->pub.need_context_rows = FALSE;

+

+  if (cinfo->CCIR601_sampling)

+    ERREXIT(cinfo, JERR_CCIR601_NOTIMPL);

+

+  /* Verify we can handle the sampling factors, and set up method pointers */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    if (compptr->h_samp_factor == cinfo->max_h_samp_factor &&

+	compptr->v_samp_factor == cinfo->max_v_samp_factor) {

+#ifdef INPUT_SMOOTHING_SUPPORTED

+      if (cinfo->smoothing_factor) {

+	downsample->methods[ci] = fullsize_smooth_downsample;

+	downsample->pub.need_context_rows = TRUE;

+      } else

+#endif

+	downsample->methods[ci] = fullsize_downsample;

+    } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&

+	       compptr->v_samp_factor == cinfo->max_v_samp_factor) {

+      smoothok = FALSE;

+      downsample->methods[ci] = h2v1_downsample;

+    } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&

+	       compptr->v_samp_factor * 2 == cinfo->max_v_samp_factor) {

+#ifdef INPUT_SMOOTHING_SUPPORTED

+      if (cinfo->smoothing_factor) {

+	downsample->methods[ci] = h2v2_smooth_downsample;

+	downsample->pub.need_context_rows = TRUE;

+      } else

+#endif

+	downsample->methods[ci] = h2v2_downsample;

+    } else if ((cinfo->max_h_samp_factor % compptr->h_samp_factor) == 0 &&

+	       (cinfo->max_v_samp_factor % compptr->v_samp_factor) == 0) {

+      smoothok = FALSE;

+      downsample->methods[ci] = int_downsample;

+    } else

+      ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);

+  }

+

+#ifdef INPUT_SMOOTHING_SUPPORTED

+  if (cinfo->smoothing_factor && !smoothok)

+    TRACEMS(cinfo, 0, JTRC_SMOOTH_NOTIMPL);

+#endif

+}

diff --git a/code/jpeg-6/jctrans.c b/code/jpeg-6/jctrans.c
new file mode 100755
index 0000000..a7b82f5
--- /dev/null
+++ b/code/jpeg-6/jctrans.c
@@ -0,0 +1,371 @@
+/*

+ * jctrans.c

+ *

+ * Copyright (C) 1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains library routines for transcoding compression,

+ * that is, writing raw DCT coefficient arrays to an output JPEG file.

+ * The routines in jcapimin.c will also be needed by a transcoder.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Forward declarations */

+LOCAL void transencode_master_selection

+	JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));

+LOCAL void transencode_coef_controller

+	JPP((j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays));

+

+

+/*

+ * Compression initialization for writing raw-coefficient data.

+ * Before calling this, all parameters and a data destination must be set up.

+ * Call jpeg_finish_compress() to actually write the data.

+ *

+ * The number of passed virtual arrays must match cinfo->num_components.

+ * Note that the virtual arrays need not be filled or even realized at

+ * the time write_coefficients is called; indeed, if the virtual arrays

+ * were requested from this compression object's memory manager, they

+ * typically will be realized during this routine and filled afterwards.

+ */

+

+GLOBAL void

+jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)

+{

+  if (cinfo->global_state != CSTATE_START)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  /* Mark all tables to be written */

+  jpeg_suppress_tables(cinfo, FALSE);

+  /* (Re)initialize error mgr and destination modules */

+  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);

+  (*cinfo->dest->init_destination) (cinfo);

+  /* Perform master selection of active modules */

+  transencode_master_selection(cinfo, coef_arrays);

+  /* Wait for jpeg_finish_compress() call */

+  cinfo->next_scanline = 0;	/* so jpeg_write_marker works */

+  cinfo->global_state = CSTATE_WRCOEFS;

+}

+

+

+/*

+ * Initialize the compression object with default parameters,

+ * then copy from the source object all parameters needed for lossless

+ * transcoding.  Parameters that can be varied without loss (such as

+ * scan script and Huffman optimization) are left in their default states.

+ */

+

+GLOBAL void

+jpeg_copy_critical_parameters (j_decompress_ptr srcinfo,

+			       j_compress_ptr dstinfo)

+{

+  JQUANT_TBL ** qtblptr;

+  jpeg_component_info *incomp, *outcomp;

+  JQUANT_TBL *c_quant, *slot_quant;

+  int tblno, ci, coefi;

+

+  /* Safety check to ensure start_compress not called yet. */

+  if (dstinfo->global_state != CSTATE_START)

+    ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state);

+  /* Copy fundamental image dimensions */

+  dstinfo->image_width = srcinfo->image_width;

+  dstinfo->image_height = srcinfo->image_height;

+  dstinfo->input_components = srcinfo->num_components;

+  dstinfo->in_color_space = srcinfo->jpeg_color_space;

+  /* Initialize all parameters to default values */

+  jpeg_set_defaults(dstinfo);

+  /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.

+   * Fix it to get the right header markers for the image colorspace.

+   */

+  jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);

+  dstinfo->data_precision = srcinfo->data_precision;

+  dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;

+  /* Copy the source's quantization tables. */

+  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {

+    if (srcinfo->quant_tbl_ptrs[tblno] != NULL) {

+      qtblptr = & dstinfo->quant_tbl_ptrs[tblno];

+      if (*qtblptr == NULL)

+	*qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo);

+      MEMCOPY((*qtblptr)->quantval,

+	      srcinfo->quant_tbl_ptrs[tblno]->quantval,

+	      SIZEOF((*qtblptr)->quantval));

+      (*qtblptr)->sent_table = FALSE;

+    }

+  }

+  /* Copy the source's per-component info.

+   * Note we assume jpeg_set_defaults has allocated the dest comp_info array.

+   */

+  dstinfo->num_components = srcinfo->num_components;

+  if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS)

+    ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,

+	     MAX_COMPONENTS);

+  for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;

+       ci < dstinfo->num_components; ci++, incomp++, outcomp++) {

+    outcomp->component_id = incomp->component_id;

+    outcomp->h_samp_factor = incomp->h_samp_factor;

+    outcomp->v_samp_factor = incomp->v_samp_factor;

+    outcomp->quant_tbl_no = incomp->quant_tbl_no;

+    /* Make sure saved quantization table for component matches the qtable

+     * slot.  If not, the input file re-used this qtable slot.

+     * IJG encoder currently cannot duplicate this.

+     */

+    tblno = outcomp->quant_tbl_no;

+    if (tblno < 0 || tblno >= NUM_QUANT_TBLS ||

+	srcinfo->quant_tbl_ptrs[tblno] == NULL)

+      ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno);

+    slot_quant = srcinfo->quant_tbl_ptrs[tblno];

+    c_quant = incomp->quant_table;

+    if (c_quant != NULL) {

+      for (coefi = 0; coefi < DCTSIZE2; coefi++) {

+	if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])

+	  ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno);

+      }

+    }

+    /* Note: we do not copy the source's Huffman table assignments;

+     * instead we rely on jpeg_set_colorspace to have made a suitable choice.

+     */

+  }

+}

+

+

+/*

+ * Master selection of compression modules for transcoding.

+ * This substitutes for jcinit.c's initialization of the full compressor.

+ */

+

+LOCAL void

+transencode_master_selection (j_compress_ptr cinfo,

+			      jvirt_barray_ptr * coef_arrays)

+{

+  /* Although we don't actually use input_components for transcoding,

+   * jcmaster.c's initial_setup will complain if input_components is 0.

+   */

+  cinfo->input_components = 1;

+  /* Initialize master control (includes parameter checking/processing) */

+  jinit_c_master_control(cinfo, TRUE /* transcode only */);

+

+  /* Entropy encoding: either Huffman or arithmetic coding. */

+  if (cinfo->arith_code) {

+    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);

+  } else {

+    if (cinfo->progressive_mode) {

+#ifdef C_PROGRESSIVE_SUPPORTED

+      jinit_phuff_encoder(cinfo);

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    } else

+      jinit_huff_encoder(cinfo);

+  }

+

+  /* We need a special coefficient buffer controller. */

+  transencode_coef_controller(cinfo, coef_arrays);

+

+  jinit_marker_writer(cinfo);

+

+  /* We can now tell the memory manager to allocate virtual arrays. */

+  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);

+

+  /* Write the datastream header (SOI) immediately.

+   * Frame and scan headers are postponed till later.

+   * This lets application insert special markers after the SOI.

+   */

+  (*cinfo->marker->write_file_header) (cinfo);

+}

+

+

+/*

+ * The rest of this file is a special implementation of the coefficient

+ * buffer controller.  This is similar to jccoefct.c, but it handles only

+ * output from presupplied virtual arrays.  Furthermore, we generate any

+ * dummy padding blocks on-the-fly rather than expecting them to be present

+ * in the arrays.

+ */

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_c_coef_controller pub; /* public fields */

+

+  JDIMENSION iMCU_row_num;	/* iMCU row # within image */

+  JDIMENSION mcu_ctr;		/* counts MCUs processed in current row */

+  int MCU_vert_offset;		/* counts MCU rows within iMCU row */

+  int MCU_rows_per_iMCU_row;	/* number of such rows needed */

+

+  /* Virtual block array for each component. */

+  jvirt_barray_ptr * whole_image;

+

+  /* Workspace for constructing dummy blocks at right/bottom edges. */

+  JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU];

+} my_coef_controller;

+

+typedef my_coef_controller * my_coef_ptr;

+

+

+LOCAL void

+start_iMCU_row (j_compress_ptr cinfo)

+/* Reset within-iMCU-row counters for a new row */

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  /* In an interleaved scan, an MCU row is the same as an iMCU row.

+   * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.

+   * But at the bottom of the image, process only what's left.

+   */

+  if (cinfo->comps_in_scan > 1) {

+    coef->MCU_rows_per_iMCU_row = 1;

+  } else {

+    if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1))

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;

+    else

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;

+  }

+

+  coef->mcu_ctr = 0;

+  coef->MCU_vert_offset = 0;

+}

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_coef (j_compress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  if (pass_mode != JBUF_CRANK_DEST)

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+

+  coef->iMCU_row_num = 0;

+  start_iMCU_row(cinfo);

+}

+

+

+/*

+ * Process some data.

+ * We process the equivalent of one fully interleaved MCU row ("iMCU" row)

+ * per call, ie, v_samp_factor block rows for each component in the scan.

+ * The data is obtained from the virtual arrays and fed to the entropy coder.

+ * Returns TRUE if the iMCU row is completed, FALSE if suspended.

+ *

+ * NB: input_buf is ignored; it is likely to be a NULL pointer.

+ */

+

+METHODDEF boolean

+compress_output (j_compress_ptr cinfo, JSAMPIMAGE input_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION MCU_col_num;	/* index of current MCU within row */

+  JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  int blkn, ci, xindex, yindex, yoffset, blockcnt;

+  JDIMENSION start_col;

+  JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];

+  JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];

+  JBLOCKROW buffer_ptr;

+  jpeg_component_info *compptr;

+

+  /* Align the virtual buffers for the components used in this scan. */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    buffer[ci] = (*cinfo->mem->access_virt_barray)

+      ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],

+       coef->iMCU_row_num * compptr->v_samp_factor,

+       (JDIMENSION) compptr->v_samp_factor, FALSE);

+  }

+

+  /* Loop to process one whole iMCU row */

+  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;

+       yoffset++) {

+    for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;

+	 MCU_col_num++) {

+      /* Construct list of pointers to DCT blocks belonging to this MCU */

+      blkn = 0;			/* index of current DCT block within MCU */

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+	compptr = cinfo->cur_comp_info[ci];

+	start_col = MCU_col_num * compptr->MCU_width;

+	blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width

+						: compptr->last_col_width;

+	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {

+	  if (coef->iMCU_row_num < last_iMCU_row ||

+	      yindex+yoffset < compptr->last_row_height) {

+	    /* Fill in pointers to real blocks in this row */

+	    buffer_ptr = buffer[ci][yindex+yoffset] + start_col;

+	    for (xindex = 0; xindex < blockcnt; xindex++)

+	      MCU_buffer[blkn++] = buffer_ptr++;

+	  } else {

+	    /* At bottom of image, need a whole row of dummy blocks */

+	    xindex = 0;

+	  }

+	  /* Fill in any dummy blocks needed in this row.

+	   * Dummy blocks are filled in the same way as in jccoefct.c:

+	   * all zeroes in the AC entries, DC entries equal to previous

+	   * block's DC value.  The init routine has already zeroed the

+	   * AC entries, so we need only set the DC entries correctly.

+	   */

+	  for (; xindex < compptr->MCU_width; xindex++) {

+	    MCU_buffer[blkn] = coef->dummy_buffer[blkn];

+	    MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0];

+	    blkn++;

+	  }

+	}

+      }

+      /* Try to write the MCU. */

+      if (! (*cinfo->entropy->encode_mcu) (cinfo, MCU_buffer)) {

+	/* Suspension forced; update state counters and exit */

+	coef->MCU_vert_offset = yoffset;

+	coef->mcu_ctr = MCU_col_num;

+	return FALSE;

+      }

+    }

+    /* Completed an MCU row, but perhaps not an iMCU row */

+    coef->mcu_ctr = 0;

+  }

+  /* Completed the iMCU row, advance counters for next one */

+  coef->iMCU_row_num++;

+  start_iMCU_row(cinfo);

+  return TRUE;

+}

+

+

+/*

+ * Initialize coefficient buffer controller.

+ *

+ * Each passed coefficient array must be the right size for that

+ * coefficient: width_in_blocks wide and height_in_blocks high,

+ * with unitheight at least v_samp_factor.

+ */

+

+LOCAL void

+transencode_coef_controller (j_compress_ptr cinfo,

+			     jvirt_barray_ptr * coef_arrays)

+{

+  my_coef_ptr coef;

+  JBLOCKROW buffer;

+  int i;

+

+  coef = (my_coef_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_coef_controller));

+  cinfo->coef = (struct jpeg_c_coef_controller *) coef;

+  coef->pub.start_pass = start_pass_coef;

+  coef->pub.compress_data = compress_output;

+

+  /* Save pointer to virtual arrays */

+  coef->whole_image = coef_arrays;

+

+  /* Allocate and pre-zero space for dummy DCT blocks. */

+  buffer = (JBLOCKROW)

+    (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));

+  jzero_far((void FAR *) buffer, C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));

+  for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {

+    coef->dummy_buffer[i] = buffer + i;

+  }

+}

diff --git a/code/jpeg-6/jdapimin.c b/code/jpeg-6/jdapimin.c
new file mode 100755
index 0000000..7be4b48
--- /dev/null
+++ b/code/jpeg-6/jdapimin.c
@@ -0,0 +1,398 @@
+/*

+ * jdapimin.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface code for the decompression half

+ * of the JPEG library.  These are the "minimum" API routines that may be

+ * needed in either the normal full-decompression case or the

+ * transcoding-only case.

+ *

+ * Most of the routines intended to be called directly by an application

+ * are in this file or in jdapistd.c.  But also see jcomapi.c for routines

+ * shared by compression and decompression, and jdtrans.c for the transcoding

+ * case.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Initialization of a JPEG decompression object.

+ * The error manager must already be set up (in case memory manager fails).

+ */

+

+GLOBAL void

+jpeg_create_decompress (j_decompress_ptr cinfo)

+{

+  int i;

+

+  /* For debugging purposes, zero the whole master structure.

+   * But error manager pointer is already there, so save and restore it.

+   */

+  {

+    struct jpeg_error_mgr * err = cinfo->err;

+    MEMZERO(cinfo, SIZEOF(struct jpeg_decompress_struct));

+    cinfo->err = err;

+  }

+  cinfo->is_decompressor = TRUE;

+

+  /* Initialize a memory manager instance for this object */

+  jinit_memory_mgr((j_common_ptr) cinfo);

+

+  /* Zero out pointers to permanent structures. */

+  cinfo->progress = NULL;

+  cinfo->src = NULL;

+

+  for (i = 0; i < NUM_QUANT_TBLS; i++)

+    cinfo->quant_tbl_ptrs[i] = NULL;

+

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    cinfo->dc_huff_tbl_ptrs[i] = NULL;

+    cinfo->ac_huff_tbl_ptrs[i] = NULL;

+  }

+

+  /* Initialize marker processor so application can override methods

+   * for COM, APPn markers before calling jpeg_read_header.

+   */

+  jinit_marker_reader(cinfo);

+

+  /* And initialize the overall input controller. */

+  jinit_input_controller(cinfo);

+

+  /* OK, I'm ready */

+  cinfo->global_state = DSTATE_START;

+}

+

+

+/*

+ * Destruction of a JPEG decompression object

+ */

+

+GLOBAL void

+jpeg_destroy_decompress (j_decompress_ptr cinfo)

+{

+  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Abort processing of a JPEG decompression operation,

+ * but don't destroy the object itself.

+ */

+

+GLOBAL void

+jpeg_abort_decompress (j_decompress_ptr cinfo)

+{

+  jpeg_abort((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Install a special processing method for COM or APPn markers.

+ */

+

+GLOBAL void

+jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code,

+			   jpeg_marker_parser_method routine)

+{

+  if (marker_code == JPEG_COM)

+    cinfo->marker->process_COM = routine;

+  else if (marker_code >= JPEG_APP0 && marker_code <= JPEG_APP0+15)

+    cinfo->marker->process_APPn[marker_code-JPEG_APP0] = routine;

+  else

+    ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code);

+}

+

+

+/*

+ * Set default decompression parameters.

+ */

+

+LOCAL void

+default_decompress_parms (j_decompress_ptr cinfo)

+{

+  /* Guess the input colorspace, and set output colorspace accordingly. */

+  /* (Wish JPEG committee had provided a real way to specify this...) */

+  /* Note application may override our guesses. */

+  switch (cinfo->num_components) {

+  case 1:

+    cinfo->jpeg_color_space = JCS_GRAYSCALE;

+    cinfo->out_color_space = JCS_GRAYSCALE;

+    break;

+    

+  case 3:

+    if (cinfo->saw_JFIF_marker) {

+      cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */

+    } else if (cinfo->saw_Adobe_marker) {

+      switch (cinfo->Adobe_transform) {

+      case 0:

+	cinfo->jpeg_color_space = JCS_RGB;

+	break;

+      case 1:

+	cinfo->jpeg_color_space = JCS_YCbCr;

+	break;

+      default:

+	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */

+	break;

+      }

+    } else {

+      /* Saw no special markers, try to guess from the component IDs */

+      int cid0 = cinfo->comp_info[0].component_id;

+      int cid1 = cinfo->comp_info[1].component_id;

+      int cid2 = cinfo->comp_info[2].component_id;

+

+      if (cid0 == 1 && cid1 == 2 && cid2 == 3)

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */

+      else if (cid0 == 82 && cid1 == 71 && cid2 == 66)

+	cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */

+      else {

+	TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */

+      }

+    }

+    /* Always guess RGB is proper output colorspace. */

+    cinfo->out_color_space = JCS_RGB;

+    break;

+    

+  case 4:

+    if (cinfo->saw_Adobe_marker) {

+      switch (cinfo->Adobe_transform) {

+      case 0:

+	cinfo->jpeg_color_space = JCS_CMYK;

+	break;

+      case 2:

+	cinfo->jpeg_color_space = JCS_YCCK;

+	break;

+      default:

+	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);

+	cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */

+	break;

+      }

+    } else {

+      /* No special markers, assume straight CMYK. */

+      cinfo->jpeg_color_space = JCS_CMYK;

+    }

+    cinfo->out_color_space = JCS_CMYK;

+    break;

+    

+  default:

+    cinfo->jpeg_color_space = JCS_UNKNOWN;

+    cinfo->out_color_space = JCS_UNKNOWN;

+    break;

+  }

+

+  /* Set defaults for other decompression parameters. */

+  cinfo->scale_num = 1;		/* 1:1 scaling */

+  cinfo->scale_denom = 1;

+  cinfo->output_gamma = 1.0;

+  cinfo->buffered_image = FALSE;

+  cinfo->raw_data_out = FALSE;

+  cinfo->dct_method = JDCT_DEFAULT;

+  cinfo->do_fancy_upsampling = TRUE;

+  cinfo->do_block_smoothing = TRUE;

+  cinfo->quantize_colors = FALSE;

+  /* We set these in case application only sets quantize_colors. */

+  cinfo->dither_mode = JDITHER_FS;

+#ifdef QUANT_2PASS_SUPPORTED

+  cinfo->two_pass_quantize = TRUE;

+#else

+  cinfo->two_pass_quantize = FALSE;

+#endif

+  cinfo->desired_number_of_colors = 256;

+  cinfo->colormap = NULL;

+  /* Initialize for no mode change in buffered-image mode. */

+  cinfo->enable_1pass_quant = FALSE;

+  cinfo->enable_external_quant = FALSE;

+  cinfo->enable_2pass_quant = FALSE;

+}

+

+

+/*

+ * Decompression startup: read start of JPEG datastream to see what's there.

+ * Need only initialize JPEG object and supply a data source before calling.

+ *

+ * This routine will read as far as the first SOS marker (ie, actual start of

+ * compressed data), and will save all tables and parameters in the JPEG

+ * object.  It will also initialize the decompression parameters to default

+ * values, and finally return JPEG_HEADER_OK.  On return, the application may

+ * adjust the decompression parameters and then call jpeg_start_decompress.

+ * (Or, if the application only wanted to determine the image parameters,

+ * the data need not be decompressed.  In that case, call jpeg_abort or

+ * jpeg_destroy to release any temporary space.)

+ * If an abbreviated (tables only) datastream is presented, the routine will

+ * return JPEG_HEADER_TABLES_ONLY upon reaching EOI.  The application may then

+ * re-use the JPEG object to read the abbreviated image datastream(s).

+ * It is unnecessary (but OK) to call jpeg_abort in this case.

+ * The JPEG_SUSPENDED return code only occurs if the data source module

+ * requests suspension of the decompressor.  In this case the application

+ * should load more source data and then re-call jpeg_read_header to resume

+ * processing.

+ * If a non-suspending data source is used and require_image is TRUE, then the

+ * return code need not be inspected since only JPEG_HEADER_OK is possible.

+ *

+ * This routine is now just a front end to jpeg_consume_input, with some

+ * extra error checking.

+ */

+

+GLOBAL int

+jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)

+{

+  int retcode;

+

+  if (cinfo->global_state != DSTATE_START &&

+      cinfo->global_state != DSTATE_INHEADER)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  retcode = jpeg_consume_input(cinfo);

+

+  switch (retcode) {

+  case JPEG_REACHED_SOS:

+    retcode = JPEG_HEADER_OK;

+    break;

+  case JPEG_REACHED_EOI:

+    if (require_image)		/* Complain if application wanted an image */

+      ERREXIT(cinfo, JERR_NO_IMAGE);

+    /* Reset to start state; it would be safer to require the application to

+     * call jpeg_abort, but we can't change it now for compatibility reasons.

+     * A side effect is to free any temporary memory (there shouldn't be any).

+     */

+    jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */

+    retcode = JPEG_HEADER_TABLES_ONLY;

+    break;

+  case JPEG_SUSPENDED:

+    /* no work */

+    break;

+  }

+

+  return retcode;

+}

+

+

+/*

+ * Consume data in advance of what the decompressor requires.

+ * This can be called at any time once the decompressor object has

+ * been created and a data source has been set up.

+ *

+ * This routine is essentially a state machine that handles a couple

+ * of critical state-transition actions, namely initial setup and

+ * transition from header scanning to ready-for-start_decompress.

+ * All the actual input is done via the input controller's consume_input

+ * method.

+ */

+

+GLOBAL int

+jpeg_consume_input (j_decompress_ptr cinfo)

+{

+  int retcode = JPEG_SUSPENDED;

+

+  /* NB: every possible DSTATE value should be listed in this switch */

+  switch (cinfo->global_state) {

+  case DSTATE_START:

+    /* Start-of-datastream actions: reset appropriate modules */

+    (*cinfo->inputctl->reset_input_controller) (cinfo);

+    /* Initialize application's data source module */

+    (*cinfo->src->init_source) (cinfo);

+    cinfo->global_state = DSTATE_INHEADER;

+    /*FALLTHROUGH*/

+  case DSTATE_INHEADER:

+    retcode = (*cinfo->inputctl->consume_input) (cinfo);

+    if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */

+      /* Set up default parameters based on header data */

+      default_decompress_parms(cinfo);

+      /* Set global state: ready for start_decompress */

+      cinfo->global_state = DSTATE_READY;

+    }

+    break;

+  case DSTATE_READY:

+    /* Can't advance past first SOS until start_decompress is called */

+    retcode = JPEG_REACHED_SOS;

+    break;

+  case DSTATE_PRELOAD:

+  case DSTATE_PRESCAN:

+  case DSTATE_SCANNING:

+  case DSTATE_RAW_OK:

+  case DSTATE_BUFIMAGE:

+  case DSTATE_BUFPOST:

+  case DSTATE_STOPPING:

+    retcode = (*cinfo->inputctl->consume_input) (cinfo);

+    break;

+  default:

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  }

+  return retcode;

+}

+

+

+/*

+ * Have we finished reading the input file?

+ */

+

+GLOBAL boolean

+jpeg_input_complete (j_decompress_ptr cinfo)

+{

+  /* Check for valid jpeg object */

+  if (cinfo->global_state < DSTATE_START ||

+      cinfo->global_state > DSTATE_STOPPING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  return cinfo->inputctl->eoi_reached;

+}

+

+

+/*

+ * Is there more than one scan?

+ */

+

+GLOBAL boolean

+jpeg_has_multiple_scans (j_decompress_ptr cinfo)

+{

+  /* Only valid after jpeg_read_header completes */

+  if (cinfo->global_state < DSTATE_READY ||

+      cinfo->global_state > DSTATE_STOPPING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  return cinfo->inputctl->has_multiple_scans;

+}

+

+

+/*

+ * Finish JPEG decompression.

+ *

+ * This will normally just verify the file trailer and release temp storage.

+ *

+ * Returns FALSE if suspended.  The return value need be inspected only if

+ * a suspending data source is used.

+ */

+

+GLOBAL boolean

+jpeg_finish_decompress (j_decompress_ptr cinfo)

+{

+  if ((cinfo->global_state == DSTATE_SCANNING ||

+       cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) {

+    /* Terminate final pass of non-buffered mode */

+    if (cinfo->output_scanline < cinfo->output_height)

+      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);

+    (*cinfo->master->finish_output_pass) (cinfo);

+    cinfo->global_state = DSTATE_STOPPING;

+  } else if (cinfo->global_state == DSTATE_BUFIMAGE) {

+    /* Finishing after a buffered-image operation */

+    cinfo->global_state = DSTATE_STOPPING;

+  } else if (cinfo->global_state != DSTATE_STOPPING) {

+    /* STOPPING = repeat call after a suspension, anything else is error */

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  }

+  /* Read until EOI */

+  while (! cinfo->inputctl->eoi_reached) {

+    if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)

+      return FALSE;		/* Suspend, come back later */

+  }

+  /* Do final cleanup */

+  (*cinfo->src->term_source) (cinfo);

+  /* We can use jpeg_abort to release memory and reset global_state */

+  jpeg_abort((j_common_ptr) cinfo);

+  return TRUE;

+}

diff --git a/code/jpeg-6/jdapistd.c b/code/jpeg-6/jdapistd.c
new file mode 100755
index 0000000..7781e16
--- /dev/null
+++ b/code/jpeg-6/jdapistd.c
@@ -0,0 +1,275 @@
+/*

+ * jdapistd.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface code for the decompression half

+ * of the JPEG library.  These are the "standard" API routines that are

+ * used in the normal full-decompression case.  They are not used by a

+ * transcoding-only application.  Note that if an application links in

+ * jpeg_start_decompress, it will end up linking in the entire decompressor.

+ * We thus must separate this file from jdapimin.c to avoid linking the

+ * whole decompression library into a transcoder.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Forward declarations */

+LOCAL boolean output_pass_setup JPP((j_decompress_ptr cinfo));

+

+

+/*

+ * Decompression initialization.

+ * jpeg_read_header must be completed before calling this.

+ *

+ * If a multipass operating mode was selected, this will do all but the

+ * last pass, and thus may take a great deal of time.

+ *

+ * Returns FALSE if suspended.  The return value need be inspected only if

+ * a suspending data source is used.

+ */

+

+GLOBAL boolean

+jpeg_start_decompress (j_decompress_ptr cinfo)

+{

+  if (cinfo->global_state == DSTATE_READY) {

+    /* First call: initialize master control, select active modules */

+    jinit_master_decompress(cinfo);

+    if (cinfo->buffered_image) {

+      /* No more work here; expecting jpeg_start_output next */

+      cinfo->global_state = DSTATE_BUFIMAGE;

+      return TRUE;

+    }

+    cinfo->global_state = DSTATE_PRELOAD;

+  }

+  if (cinfo->global_state == DSTATE_PRELOAD) {

+    /* If file has multiple scans, absorb them all into the coef buffer */

+    if (cinfo->inputctl->has_multiple_scans) {

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+      for (;;) {

+	int retcode;

+	/* Call progress monitor hook if present */

+	if (cinfo->progress != NULL)

+	  (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+	/* Absorb some more input */

+	retcode = (*cinfo->inputctl->consume_input) (cinfo);

+	if (retcode == JPEG_SUSPENDED)

+	  return FALSE;

+	if (retcode == JPEG_REACHED_EOI)

+	  break;

+	/* Advance progress counter if appropriate */

+	if (cinfo->progress != NULL &&

+	    (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) {

+	  if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) {

+	    /* jdmaster underestimated number of scans; ratchet up one scan */

+	    cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows;

+	  }

+	}

+      }

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif /* D_MULTISCAN_FILES_SUPPORTED */

+    }

+    cinfo->output_scan_number = cinfo->input_scan_number;

+  } else if (cinfo->global_state != DSTATE_PRESCAN)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  /* Perform any dummy output passes, and set up for the final pass */

+  return output_pass_setup(cinfo);

+}

+

+

+/*

+ * Set up for an output pass, and perform any dummy pass(es) needed.

+ * Common subroutine for jpeg_start_decompress and jpeg_start_output.

+ * Entry: global_state = DSTATE_PRESCAN only if previously suspended.

+ * Exit: If done, returns TRUE and sets global_state for proper output mode.

+ *       If suspended, returns FALSE and sets global_state = DSTATE_PRESCAN.

+ */

+

+LOCAL boolean

+output_pass_setup (j_decompress_ptr cinfo)

+{

+  if (cinfo->global_state != DSTATE_PRESCAN) {

+    /* First call: do pass setup */

+    (*cinfo->master->prepare_for_output_pass) (cinfo);

+    cinfo->output_scanline = 0;

+    cinfo->global_state = DSTATE_PRESCAN;

+  }

+  /* Loop over any required dummy passes */

+  while (cinfo->master->is_dummy_pass) {

+#ifdef QUANT_2PASS_SUPPORTED

+    /* Crank through the dummy pass */

+    while (cinfo->output_scanline < cinfo->output_height) {

+      JDIMENSION last_scanline;

+      /* Call progress monitor hook if present */

+      if (cinfo->progress != NULL) {

+	cinfo->progress->pass_counter = (long) cinfo->output_scanline;

+	cinfo->progress->pass_limit = (long) cinfo->output_height;

+	(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+      }

+      /* Process some data */

+      last_scanline = cinfo->output_scanline;

+      (*cinfo->main->process_data) (cinfo, (JSAMPARRAY) NULL,

+				    &cinfo->output_scanline, (JDIMENSION) 0);

+      if (cinfo->output_scanline == last_scanline)

+	return FALSE;		/* No progress made, must suspend */

+    }

+    /* Finish up dummy pass, and set up for another one */

+    (*cinfo->master->finish_output_pass) (cinfo);

+    (*cinfo->master->prepare_for_output_pass) (cinfo);

+    cinfo->output_scanline = 0;

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif /* QUANT_2PASS_SUPPORTED */

+  }

+  /* Ready for application to drive output pass through

+   * jpeg_read_scanlines or jpeg_read_raw_data.

+   */

+  cinfo->global_state = cinfo->raw_data_out ? DSTATE_RAW_OK : DSTATE_SCANNING;

+  return TRUE;

+}

+

+

+/*

+ * Read some scanlines of data from the JPEG decompressor.

+ *

+ * The return value will be the number of lines actually read.

+ * This may be less than the number requested in several cases,

+ * including bottom of image, data source suspension, and operating

+ * modes that emit multiple scanlines at a time.

+ *

+ * Note: we warn about excess calls to jpeg_read_scanlines() since

+ * this likely signals an application programmer error.  However,

+ * an oversize buffer (max_lines > scanlines remaining) is not an error.

+ */

+

+GLOBAL JDIMENSION

+jpeg_read_scanlines (j_decompress_ptr cinfo, JSAMPARRAY scanlines,

+		     JDIMENSION max_lines)

+{

+  JDIMENSION row_ctr;

+

+  if (cinfo->global_state != DSTATE_SCANNING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  if (cinfo->output_scanline >= cinfo->output_height) {

+    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);

+    return 0;

+  }

+

+  /* Call progress monitor hook if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->pass_counter = (long) cinfo->output_scanline;

+    cinfo->progress->pass_limit = (long) cinfo->output_height;

+    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+  }

+

+  /* Process some data */

+  row_ctr = 0;

+  (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, max_lines);

+  cinfo->output_scanline += row_ctr;

+  return row_ctr;

+}

+

+

+/*

+ * Alternate entry point to read raw data.

+ * Processes exactly one iMCU row per call, unless suspended.

+ */

+

+GLOBAL JDIMENSION

+jpeg_read_raw_data (j_decompress_ptr cinfo, JSAMPIMAGE data,

+		    JDIMENSION max_lines)

+{

+  JDIMENSION lines_per_iMCU_row;

+

+  if (cinfo->global_state != DSTATE_RAW_OK)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  if (cinfo->output_scanline >= cinfo->output_height) {

+    WARNMS(cinfo, JWRN_TOO_MUCH_DATA);

+    return 0;

+  }

+

+  /* Call progress monitor hook if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->pass_counter = (long) cinfo->output_scanline;

+    cinfo->progress->pass_limit = (long) cinfo->output_height;

+    (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+  }

+

+  /* Verify that at least one iMCU row can be returned. */

+  lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size;

+  if (max_lines < lines_per_iMCU_row)

+    ERREXIT(cinfo, JERR_BUFFER_SIZE);

+

+  /* Decompress directly into user's buffer. */

+  if (! (*cinfo->coef->decompress_data) (cinfo, data))

+    return 0;			/* suspension forced, can do nothing more */

+

+  /* OK, we processed one iMCU row. */

+  cinfo->output_scanline += lines_per_iMCU_row;

+  return lines_per_iMCU_row;

+}

+

+

+/* Additional entry points for buffered-image mode. */

+

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+

+/*

+ * Initialize for an output pass in buffered-image mode.

+ */

+

+GLOBAL boolean

+jpeg_start_output (j_decompress_ptr cinfo, int scan_number)

+{

+  if (cinfo->global_state != DSTATE_BUFIMAGE &&

+      cinfo->global_state != DSTATE_PRESCAN)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  /* Limit scan number to valid range */

+  if (scan_number <= 0)

+    scan_number = 1;

+  if (cinfo->inputctl->eoi_reached &&

+      scan_number > cinfo->input_scan_number)

+    scan_number = cinfo->input_scan_number;

+  cinfo->output_scan_number = scan_number;

+  /* Perform any dummy output passes, and set up for the real pass */

+  return output_pass_setup(cinfo);

+}

+

+

+/*

+ * Finish up after an output pass in buffered-image mode.

+ *

+ * Returns FALSE if suspended.  The return value need be inspected only if

+ * a suspending data source is used.

+ */

+

+GLOBAL boolean

+jpeg_finish_output (j_decompress_ptr cinfo)

+{

+  if ((cinfo->global_state == DSTATE_SCANNING ||

+       cinfo->global_state == DSTATE_RAW_OK) && cinfo->buffered_image) {

+    /* Terminate this pass. */

+    /* We do not require the whole pass to have been completed. */

+    (*cinfo->master->finish_output_pass) (cinfo);

+    cinfo->global_state = DSTATE_BUFPOST;

+  } else if (cinfo->global_state != DSTATE_BUFPOST) {

+    /* BUFPOST = repeat call after a suspension, anything else is error */

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  }

+  /* Read markers looking for SOS or EOI */

+  while (cinfo->input_scan_number <= cinfo->output_scan_number &&

+	 ! cinfo->inputctl->eoi_reached) {

+    if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)

+      return FALSE;		/* Suspend, come back later */

+  }

+  cinfo->global_state = DSTATE_BUFIMAGE;

+  return TRUE;

+}

+

+#endif /* D_MULTISCAN_FILES_SUPPORTED */

diff --git a/code/jpeg-6/jdatadst.c b/code/jpeg-6/jdatadst.c
new file mode 100755
index 0000000..748bca5
--- /dev/null
+++ b/code/jpeg-6/jdatadst.c
@@ -0,0 +1,151 @@
+/*

+ * jdatadst.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains compression data destination routines for the case of

+ * emitting JPEG data to a file (or any stdio stream).  While these routines

+ * are sufficient for most applications, some will want to use a different

+ * destination manager.

+ * IMPORTANT: we assume that fwrite() will correctly transcribe an array of

+ * JOCTETs into 8-bit-wide elements on external storage.  If char is wider

+ * than 8 bits on your machine, you may need to do some tweaking.

+ */

+

+/* this is not a core library module, so it doesn't define JPEG_INTERNALS */

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jerror.h"

+

+

+/* Expanded data destination object for stdio output */

+

+typedef struct {

+  struct jpeg_destination_mgr pub; /* public fields */

+

+  FILE * outfile;		/* target stream */

+  JOCTET * buffer;		/* start of buffer */

+} my_destination_mgr;

+

+typedef my_destination_mgr * my_dest_ptr;

+

+#define OUTPUT_BUF_SIZE  4096	/* choose an efficiently fwrite'able size */

+

+

+/*

+ * Initialize destination --- called by jpeg_start_compress

+ * before any data is actually written.

+ */

+

+METHODDEF void

+init_destination (j_compress_ptr cinfo)

+{

+  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;

+

+  /* Allocate the output buffer --- it will be released when done with image */

+  dest->buffer = (JOCTET *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  OUTPUT_BUF_SIZE * SIZEOF(JOCTET));

+

+  dest->pub.next_output_byte = dest->buffer;

+  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;

+}

+

+

+/*

+ * Empty the output buffer --- called whenever buffer fills up.

+ *

+ * In typical applications, this should write the entire output buffer

+ * (ignoring the current state of next_output_byte & free_in_buffer),

+ * reset the pointer & count to the start of the buffer, and return TRUE

+ * indicating that the buffer has been dumped.

+ *

+ * In applications that need to be able to suspend compression due to output

+ * overrun, a FALSE return indicates that the buffer cannot be emptied now.

+ * In this situation, the compressor will return to its caller (possibly with

+ * an indication that it has not accepted all the supplied scanlines).  The

+ * application should resume compression after it has made more room in the

+ * output buffer.  Note that there are substantial restrictions on the use of

+ * suspension --- see the documentation.

+ *

+ * When suspending, the compressor will back up to a convenient restart point

+ * (typically the start of the current MCU). next_output_byte & free_in_buffer

+ * indicate where the restart point will be if the current call returns FALSE.

+ * Data beyond this point will be regenerated after resumption, so do not

+ * write it out when emptying the buffer externally.

+ */

+

+METHODDEF boolean

+empty_output_buffer (j_compress_ptr cinfo)

+{

+  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;

+

+  if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) !=

+      (size_t) OUTPUT_BUF_SIZE)

+    ERREXIT(cinfo, JERR_FILE_WRITE);

+

+  dest->pub.next_output_byte = dest->buffer;

+  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;

+

+  return TRUE;

+}

+

+

+/*

+ * Terminate destination --- called by jpeg_finish_compress

+ * after all data has been written.  Usually needs to flush buffer.

+ *

+ * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding

+ * application must deal with any cleanup that should happen even

+ * for error exit.

+ */

+

+METHODDEF void

+term_destination (j_compress_ptr cinfo)

+{

+  my_dest_ptr dest = (my_dest_ptr) cinfo->dest;

+  size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;

+

+  /* Write any data remaining in the buffer */

+  if (datacount > 0) {

+    if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount)

+      ERREXIT(cinfo, JERR_FILE_WRITE);

+  }

+  fflush(dest->outfile);

+  /* Make sure we wrote the output file OK */

+  if (ferror(dest->outfile))

+    ERREXIT(cinfo, JERR_FILE_WRITE);

+}

+

+

+/*

+ * Prepare for output to a stdio stream.

+ * The caller must have already opened the stream, and is responsible

+ * for closing it after finishing compression.

+ */

+

+GLOBAL void

+jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile)

+{

+  my_dest_ptr dest;

+

+  /* The destination object is made permanent so that multiple JPEG images

+   * can be written to the same file without re-executing jpeg_stdio_dest.

+   * This makes it dangerous to use this manager and a different destination

+   * manager serially with the same JPEG object, because their private object

+   * sizes may be different.  Caveat programmer.

+   */

+  if (cinfo->dest == NULL) {	/* first time for this JPEG object? */

+    cinfo->dest = (struct jpeg_destination_mgr *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				  SIZEOF(my_destination_mgr));

+  }

+

+  dest = (my_dest_ptr) cinfo->dest;

+  dest->pub.init_destination = init_destination;

+  dest->pub.empty_output_buffer = empty_output_buffer;

+  dest->pub.term_destination = term_destination;

+  dest->outfile = outfile;

+}

diff --git a/code/jpeg-6/jdatasrc.c b/code/jpeg-6/jdatasrc.c
new file mode 100755
index 0000000..5c1696d
--- /dev/null
+++ b/code/jpeg-6/jdatasrc.c
@@ -0,0 +1,204 @@
+/*

+ * jdatasrc.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains decompression data source routines for the case of

+ * reading JPEG data from a file (or any stdio stream).  While these routines

+ * are sufficient for most applications, some will want to use a different

+ * source manager.

+ * IMPORTANT: we assume that fread() will correctly transcribe an array of

+ * JOCTETs from 8-bit-wide elements on external storage.  If char is wider

+ * than 8 bits on your machine, you may need to do some tweaking.

+ */

+

+

+/* this is not a core library module, so it doesn't define JPEG_INTERNALS */

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jerror.h"

+

+

+/* Expanded data source object for stdio input */

+

+typedef struct {

+  struct jpeg_source_mgr pub;	/* public fields */

+

+  unsigned char *infile;		/* source stream */

+  JOCTET * buffer;		/* start of buffer */

+  boolean start_of_file;	/* have we gotten any data yet? */

+} my_source_mgr;

+

+typedef my_source_mgr * my_src_ptr;

+

+#define INPUT_BUF_SIZE  4096	/* choose an efficiently fread'able size */

+

+

+/*

+ * Initialize source --- called by jpeg_read_header

+ * before any data is actually read.

+ */

+

+METHODDEF void

+init_source (j_decompress_ptr cinfo)

+{

+  my_src_ptr src = (my_src_ptr) cinfo->src;

+

+  /* We reset the empty-input-file flag for each image,

+   * but we don't clear the input buffer.

+   * This is correct behavior for reading a series of images from one source.

+   */

+  src->start_of_file = TRUE;

+}

+

+

+/*

+ * Fill the input buffer --- called whenever buffer is emptied.

+ *

+ * In typical applications, this should read fresh data into the buffer

+ * (ignoring the current state of next_input_byte & bytes_in_buffer),

+ * reset the pointer & count to the start of the buffer, and return TRUE

+ * indicating that the buffer has been reloaded.  It is not necessary to

+ * fill the buffer entirely, only to obtain at least one more byte.

+ *

+ * There is no such thing as an EOF return.  If the end of the file has been

+ * reached, the routine has a choice of ERREXIT() or inserting fake data into

+ * the buffer.  In most cases, generating a warning message and inserting a

+ * fake EOI marker is the best course of action --- this will allow the

+ * decompressor to output however much of the image is there.  However,

+ * the resulting error message is misleading if the real problem is an empty

+ * input file, so we handle that case specially.

+ *

+ * In applications that need to be able to suspend compression due to input

+ * not being available yet, a FALSE return indicates that no more data can be

+ * obtained right now, but more may be forthcoming later.  In this situation,

+ * the decompressor will return to its caller (with an indication of the

+ * number of scanlines it has read, if any).  The application should resume

+ * decompression after it has loaded more data into the input buffer.  Note

+ * that there are substantial restrictions on the use of suspension --- see

+ * the documentation.

+ *

+ * When suspending, the decompressor will back up to a convenient restart point

+ * (typically the start of the current MCU). next_input_byte & bytes_in_buffer

+ * indicate where the restart point will be if the current call returns FALSE.

+ * Data beyond this point must be rescanned after resumption, so move it to

+ * the front of the buffer rather than discarding it.

+ */

+

+METHODDEF boolean

+fill_input_buffer (j_decompress_ptr cinfo)

+{

+  my_src_ptr src = (my_src_ptr) cinfo->src;

+

+  memcpy( src->buffer, src->infile, INPUT_BUF_SIZE );

+

+  src->infile += INPUT_BUF_SIZE;

+

+  src->pub.next_input_byte = src->buffer;

+  src->pub.bytes_in_buffer = INPUT_BUF_SIZE;

+  src->start_of_file = FALSE;

+

+  return TRUE;

+}

+

+

+/*

+ * Skip data --- used to skip over a potentially large amount of

+ * uninteresting data (such as an APPn marker).

+ *

+ * Writers of suspendable-input applications must note that skip_input_data

+ * is not granted the right to give a suspension return.  If the skip extends

+ * beyond the data currently in the buffer, the buffer can be marked empty so

+ * that the next read will cause a fill_input_buffer call that can suspend.

+ * Arranging for additional bytes to be discarded before reloading the input

+ * buffer is the application writer's problem.

+ */

+

+METHODDEF void

+skip_input_data (j_decompress_ptr cinfo, long num_bytes)

+{

+  my_src_ptr src = (my_src_ptr) cinfo->src;

+

+  /* Just a dumb implementation for now.  Could use fseek() except

+   * it doesn't work on pipes.  Not clear that being smart is worth

+   * any trouble anyway --- large skips are infrequent.

+   */

+  if (num_bytes > 0) {

+    while (num_bytes > (long) src->pub.bytes_in_buffer) {

+      num_bytes -= (long) src->pub.bytes_in_buffer;

+      (void) fill_input_buffer(cinfo);

+      /* note we assume that fill_input_buffer will never return FALSE,

+       * so suspension need not be handled.

+       */

+    }

+    src->pub.next_input_byte += (size_t) num_bytes;

+    src->pub.bytes_in_buffer -= (size_t) num_bytes;

+  }

+}

+

+

+/*

+ * An additional method that can be provided by data source modules is the

+ * resync_to_restart method for error recovery in the presence of RST markers.

+ * For the moment, this source module just uses the default resync method

+ * provided by the JPEG library.  That method assumes that no backtracking

+ * is possible.

+ */

+

+

+/*

+ * Terminate source --- called by jpeg_finish_decompress

+ * after all data has been read.  Often a no-op.

+ *

+ * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding

+ * application must deal with any cleanup that should happen even

+ * for error exit.

+ */

+

+METHODDEF void

+term_source (j_decompress_ptr cinfo)

+{

+  /* no work necessary here */

+}

+

+

+/*

+ * Prepare for input from a stdio stream.

+ * The caller must have already opened the stream, and is responsible

+ * for closing it after finishing decompression.

+ */

+

+GLOBAL void

+jpeg_stdio_src (j_decompress_ptr cinfo, unsigned char *infile)

+{

+  my_src_ptr src;

+

+  /* The source object and input buffer are made permanent so that a series

+   * of JPEG images can be read from the same file by calling jpeg_stdio_src

+   * only before the first one.  (If we discarded the buffer at the end of

+   * one image, we'd likely lose the start of the next one.)

+   * This makes it unsafe to use this manager and a different source

+   * manager serially with the same JPEG object.  Caveat programmer.

+   */

+  if (cinfo->src == NULL) {	/* first time for this JPEG object? */

+    cinfo->src = (struct jpeg_source_mgr *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				  SIZEOF(my_source_mgr));

+    src = (my_src_ptr) cinfo->src;

+    src->buffer = (JOCTET *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				  INPUT_BUF_SIZE * SIZEOF(JOCTET));

+  }

+

+  src = (my_src_ptr) cinfo->src;

+  src->pub.init_source = init_source;

+  src->pub.fill_input_buffer = fill_input_buffer;

+  src->pub.skip_input_data = skip_input_data;

+  src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */

+  src->pub.term_source = term_source;

+  src->infile = infile;

+  src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */

+  src->pub.next_input_byte = NULL; /* until buffer loaded */

+}

diff --git a/code/jpeg-6/jdcoefct.c b/code/jpeg-6/jdcoefct.c
new file mode 100755
index 0000000..2b20c07
--- /dev/null
+++ b/code/jpeg-6/jdcoefct.c
@@ -0,0 +1,725 @@
+/*

+ * jdcoefct.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the coefficient buffer controller for decompression.

+ * This controller is the top level of the JPEG decompressor proper.

+ * The coefficient buffer lies between entropy decoding and inverse-DCT steps.

+ *

+ * In buffered-image mode, this controller is the interface between

+ * input-oriented processing and output-oriented processing.

+ * Also, the input side (only) is used when reading a file for transcoding.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+/* Block smoothing is only applicable for progressive JPEG, so: */

+#ifndef D_PROGRESSIVE_SUPPORTED

+#undef BLOCK_SMOOTHING_SUPPORTED

+#endif

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_d_coef_controller pub; /* public fields */

+

+  /* These variables keep track of the current location of the input side. */

+  /* cinfo->input_iMCU_row is also used for this. */

+  JDIMENSION MCU_ctr;		/* counts MCUs processed in current row */

+  int MCU_vert_offset;		/* counts MCU rows within iMCU row */

+  int MCU_rows_per_iMCU_row;	/* number of such rows needed */

+

+  /* The output side's location is represented by cinfo->output_iMCU_row. */

+

+  /* In single-pass modes, it's sufficient to buffer just one MCU.

+   * We allocate a workspace of D_MAX_BLOCKS_IN_MCU coefficient blocks,

+   * and let the entropy decoder write into that workspace each time.

+   * (On 80x86, the workspace is FAR even though it's not really very big;

+   * this is to keep the module interfaces unchanged when a large coefficient

+   * buffer is necessary.)

+   * In multi-pass modes, this array points to the current MCU's blocks

+   * within the virtual arrays; it is used only by the input side.

+   */

+  JBLOCKROW MCU_buffer[D_MAX_BLOCKS_IN_MCU];

+

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+  /* In multi-pass modes, we need a virtual block array for each component. */

+  jvirt_barray_ptr whole_image[MAX_COMPONENTS];

+#endif

+

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+  /* When doing block smoothing, we latch coefficient Al values here */

+  int * coef_bits_latch;

+#define SAVED_COEFS  6		/* we save coef_bits[0..5] */

+#endif

+} my_coef_controller;

+

+typedef my_coef_controller * my_coef_ptr;

+

+/* Forward declarations */

+METHODDEF int decompress_onepass

+	JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+METHODDEF int decompress_data

+	JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));

+#endif

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+LOCAL boolean smoothing_ok JPP((j_decompress_ptr cinfo));

+METHODDEF int decompress_smooth_data

+	JPP((j_decompress_ptr cinfo, JSAMPIMAGE output_buf));

+#endif

+

+

+LOCAL void

+start_iMCU_row (j_decompress_ptr cinfo)

+/* Reset within-iMCU-row counters for a new row (input side) */

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  /* In an interleaved scan, an MCU row is the same as an iMCU row.

+   * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.

+   * But at the bottom of the image, process only what's left.

+   */

+  if (cinfo->comps_in_scan > 1) {

+    coef->MCU_rows_per_iMCU_row = 1;

+  } else {

+    if (cinfo->input_iMCU_row < (cinfo->total_iMCU_rows-1))

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;

+    else

+      coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;

+  }

+

+  coef->MCU_ctr = 0;

+  coef->MCU_vert_offset = 0;

+}

+

+

+/*

+ * Initialize for an input processing pass.

+ */

+

+METHODDEF void

+start_input_pass (j_decompress_ptr cinfo)

+{

+  cinfo->input_iMCU_row = 0;

+  start_iMCU_row(cinfo);

+}

+

+

+/*

+ * Initialize for an output processing pass.

+ */

+

+METHODDEF void

+start_output_pass (j_decompress_ptr cinfo)

+{

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+

+  /* If multipass, check to see whether to use block smoothing on this pass */

+  if (coef->pub.coef_arrays != NULL) {

+    if (cinfo->do_block_smoothing && smoothing_ok(cinfo))

+      coef->pub.decompress_data = decompress_smooth_data;

+    else

+      coef->pub.decompress_data = decompress_data;

+  }

+#endif

+  cinfo->output_iMCU_row = 0;

+}

+

+

+/*

+ * Decompress and return some data in the single-pass case.

+ * Always attempts to emit one fully interleaved MCU row ("iMCU" row).

+ * Input and output must run in lockstep since we have only a one-MCU buffer.

+ * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.

+ *

+ * NB: output_buf contains a plane for each component in image.

+ * For single pass, this is the same as the components in the scan.

+ */

+

+METHODDEF int

+decompress_onepass (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION MCU_col_num;	/* index of current MCU within row */

+  JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  int blkn, ci, xindex, yindex, yoffset, useful_width;

+  JSAMPARRAY output_ptr;

+  JDIMENSION start_col, output_col;

+  jpeg_component_info *compptr;

+  inverse_DCT_method_ptr inverse_DCT;

+

+  /* Loop to process as much as one whole iMCU row */

+  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;

+       yoffset++) {

+    for (MCU_col_num = coef->MCU_ctr; MCU_col_num <= last_MCU_col;

+	 MCU_col_num++) {

+      /* Try to fetch an MCU.  Entropy decoder expects buffer to be zeroed. */

+      jzero_far((void FAR *) coef->MCU_buffer[0],

+		(size_t) (cinfo->blocks_in_MCU * SIZEOF(JBLOCK)));

+      if (! (*cinfo->entropy->decode_mcu) (cinfo, coef->MCU_buffer)) {

+	/* Suspension forced; update state counters and exit */

+	coef->MCU_vert_offset = yoffset;

+	coef->MCU_ctr = MCU_col_num;

+	return JPEG_SUSPENDED;

+      }

+      /* Determine where data should go in output_buf and do the IDCT thing.

+       * We skip dummy blocks at the right and bottom edges (but blkn gets

+       * incremented past them!).  Note the inner loop relies on having

+       * allocated the MCU_buffer[] blocks sequentially.

+       */

+      blkn = 0;			/* index of current DCT block within MCU */

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+	compptr = cinfo->cur_comp_info[ci];

+	/* Don't bother to IDCT an uninteresting component. */

+	if (! compptr->component_needed) {

+	  blkn += compptr->MCU_blocks;

+	  continue;

+	}

+	inverse_DCT = cinfo->idct->inverse_DCT[compptr->component_index];

+	useful_width = (MCU_col_num < last_MCU_col) ? compptr->MCU_width

+						    : compptr->last_col_width;

+	output_ptr = output_buf[ci] + yoffset * compptr->DCT_scaled_size;

+	start_col = MCU_col_num * compptr->MCU_sample_width;

+	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {

+	  if (cinfo->input_iMCU_row < last_iMCU_row ||

+	      yoffset+yindex < compptr->last_row_height) {

+	    output_col = start_col;

+	    for (xindex = 0; xindex < useful_width; xindex++) {

+	      (*inverse_DCT) (cinfo, compptr,

+			      (JCOEFPTR) coef->MCU_buffer[blkn+xindex],

+			      output_ptr, output_col);

+	      output_col += compptr->DCT_scaled_size;

+	    }

+	  }

+	  blkn += compptr->MCU_width;

+	  output_ptr += compptr->DCT_scaled_size;

+	}

+      }

+    }

+    /* Completed an MCU row, but perhaps not an iMCU row */

+    coef->MCU_ctr = 0;

+  }

+  /* Completed the iMCU row, advance counters for next one */

+  cinfo->output_iMCU_row++;

+  if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {

+    start_iMCU_row(cinfo);

+    return JPEG_ROW_COMPLETED;

+  }

+  /* Completed the scan */

+  (*cinfo->inputctl->finish_input_pass) (cinfo);

+  return JPEG_SCAN_COMPLETED;

+}

+

+

+/*

+ * Dummy consume-input routine for single-pass operation.

+ */

+

+METHODDEF int

+dummy_consume_data (j_decompress_ptr cinfo)

+{

+  return JPEG_SUSPENDED;	/* Always indicate nothing was done */

+}

+

+

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+

+/*

+ * Consume input data and store it in the full-image coefficient buffer.

+ * We read as much as one fully interleaved MCU row ("iMCU" row) per call,

+ * ie, v_samp_factor block rows for each component in the scan.

+ * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.

+ */

+

+METHODDEF int

+consume_data (j_decompress_ptr cinfo)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION MCU_col_num;	/* index of current MCU within row */

+  int blkn, ci, xindex, yindex, yoffset;

+  JDIMENSION start_col;

+  JBLOCKARRAY buffer[MAX_COMPS_IN_SCAN];

+  JBLOCKROW buffer_ptr;

+  jpeg_component_info *compptr;

+

+  /* Align the virtual buffers for the components used in this scan. */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    buffer[ci] = (*cinfo->mem->access_virt_barray)

+      ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],

+       cinfo->input_iMCU_row * compptr->v_samp_factor,

+       (JDIMENSION) compptr->v_samp_factor, TRUE);

+    /* Note: entropy decoder expects buffer to be zeroed,

+     * but this is handled automatically by the memory manager

+     * because we requested a pre-zeroed array.

+     */

+  }

+

+  /* Loop to process one whole iMCU row */

+  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;

+       yoffset++) {

+    for (MCU_col_num = coef->MCU_ctr; MCU_col_num < cinfo->MCUs_per_row;

+	 MCU_col_num++) {

+      /* Construct list of pointers to DCT blocks belonging to this MCU */

+      blkn = 0;			/* index of current DCT block within MCU */

+      for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+	compptr = cinfo->cur_comp_info[ci];

+	start_col = MCU_col_num * compptr->MCU_width;

+	for (yindex = 0; yindex < compptr->MCU_height; yindex++) {

+	  buffer_ptr = buffer[ci][yindex+yoffset] + start_col;

+	  for (xindex = 0; xindex < compptr->MCU_width; xindex++) {

+	    coef->MCU_buffer[blkn++] = buffer_ptr++;

+	  }

+	}

+      }

+      /* Try to fetch the MCU. */

+      if (! (*cinfo->entropy->decode_mcu) (cinfo, coef->MCU_buffer)) {

+	/* Suspension forced; update state counters and exit */

+	coef->MCU_vert_offset = yoffset;

+	coef->MCU_ctr = MCU_col_num;

+	return JPEG_SUSPENDED;

+      }

+    }

+    /* Completed an MCU row, but perhaps not an iMCU row */

+    coef->MCU_ctr = 0;

+  }

+  /* Completed the iMCU row, advance counters for next one */

+  if (++(cinfo->input_iMCU_row) < cinfo->total_iMCU_rows) {

+    start_iMCU_row(cinfo);

+    return JPEG_ROW_COMPLETED;

+  }

+  /* Completed the scan */

+  (*cinfo->inputctl->finish_input_pass) (cinfo);

+  return JPEG_SCAN_COMPLETED;

+}

+

+

+/*

+ * Decompress and return some data in the multi-pass case.

+ * Always attempts to emit one fully interleaved MCU row ("iMCU" row).

+ * Return value is JPEG_ROW_COMPLETED, JPEG_SCAN_COMPLETED, or JPEG_SUSPENDED.

+ *

+ * NB: output_buf contains a plane for each component in image.

+ */

+

+METHODDEF int

+decompress_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  JDIMENSION block_num;

+  int ci, block_row, block_rows;

+  JBLOCKARRAY buffer;

+  JBLOCKROW buffer_ptr;

+  JSAMPARRAY output_ptr;

+  JDIMENSION output_col;

+  jpeg_component_info *compptr;

+  inverse_DCT_method_ptr inverse_DCT;

+

+  /* Force some input to be done if we are getting ahead of the input. */

+  while (cinfo->input_scan_number < cinfo->output_scan_number ||

+	 (cinfo->input_scan_number == cinfo->output_scan_number &&

+	  cinfo->input_iMCU_row <= cinfo->output_iMCU_row)) {

+    if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED)

+      return JPEG_SUSPENDED;

+  }

+

+  /* OK, output from the virtual arrays. */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Don't bother to IDCT an uninteresting component. */

+    if (! compptr->component_needed)

+      continue;

+    /* Align the virtual buffer for this component. */

+    buffer = (*cinfo->mem->access_virt_barray)

+      ((j_common_ptr) cinfo, coef->whole_image[ci],

+       cinfo->output_iMCU_row * compptr->v_samp_factor,

+       (JDIMENSION) compptr->v_samp_factor, FALSE);

+    /* Count non-dummy DCT block rows in this iMCU row. */

+    if (cinfo->output_iMCU_row < last_iMCU_row)

+      block_rows = compptr->v_samp_factor;

+    else {

+      /* NB: can't use last_row_height here; it is input-side-dependent! */

+      block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);

+      if (block_rows == 0) block_rows = compptr->v_samp_factor;

+    }

+    inverse_DCT = cinfo->idct->inverse_DCT[ci];

+    output_ptr = output_buf[ci];

+    /* Loop over all DCT blocks to be processed. */

+    for (block_row = 0; block_row < block_rows; block_row++) {

+      buffer_ptr = buffer[block_row];

+      output_col = 0;

+      for (block_num = 0; block_num < compptr->width_in_blocks; block_num++) {

+	(*inverse_DCT) (cinfo, compptr, (JCOEFPTR) buffer_ptr,

+			output_ptr, output_col);

+	buffer_ptr++;

+	output_col += compptr->DCT_scaled_size;

+      }

+      output_ptr += compptr->DCT_scaled_size;

+    }

+  }

+

+  if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows)

+    return JPEG_ROW_COMPLETED;

+  return JPEG_SCAN_COMPLETED;

+}

+

+#endif /* D_MULTISCAN_FILES_SUPPORTED */

+

+

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+

+/*

+ * This code applies interblock smoothing as described by section K.8

+ * of the JPEG standard: the first 5 AC coefficients are estimated from

+ * the DC values of a DCT block and its 8 neighboring blocks.

+ * We apply smoothing only for progressive JPEG decoding, and only if

+ * the coefficients it can estimate are not yet known to full precision.

+ */

+

+/*

+ * Determine whether block smoothing is applicable and safe.

+ * We also latch the current states of the coef_bits[] entries for the

+ * AC coefficients; otherwise, if the input side of the decompressor

+ * advances into a new scan, we might think the coefficients are known

+ * more accurately than they really are.

+ */

+

+LOCAL boolean

+smoothing_ok (j_decompress_ptr cinfo)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  boolean smoothing_useful = FALSE;

+  int ci, coefi;

+  jpeg_component_info *compptr;

+  JQUANT_TBL * qtable;

+  int * coef_bits;

+  int * coef_bits_latch;

+

+  if (! cinfo->progressive_mode || cinfo->coef_bits == NULL)

+    return FALSE;

+

+  /* Allocate latch area if not already done */

+  if (coef->coef_bits_latch == NULL)

+    coef->coef_bits_latch = (int *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  cinfo->num_components *

+				  (SAVED_COEFS * SIZEOF(int)));

+  coef_bits_latch = coef->coef_bits_latch;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* All components' quantization values must already be latched. */

+    if ((qtable = compptr->quant_table) == NULL)

+      return FALSE;

+    /* Verify DC & first 5 AC quantizers are nonzero to avoid zero-divide. */

+    for (coefi = 0; coefi <= 5; coefi++) {

+      if (qtable->quantval[coefi] == 0)

+	return FALSE;

+    }

+    /* DC values must be at least partly known for all components. */

+    coef_bits = cinfo->coef_bits[ci];

+    if (coef_bits[0] < 0)

+      return FALSE;

+    /* Block smoothing is helpful if some AC coefficients remain inaccurate. */

+    for (coefi = 1; coefi <= 5; coefi++) {

+      coef_bits_latch[coefi] = coef_bits[coefi];

+      if (coef_bits[coefi] != 0)

+	smoothing_useful = TRUE;

+    }

+    coef_bits_latch += SAVED_COEFS;

+  }

+

+  return smoothing_useful;

+}

+

+

+/*

+ * Variant of decompress_data for use when doing block smoothing.

+ */

+

+METHODDEF int

+decompress_smooth_data (j_decompress_ptr cinfo, JSAMPIMAGE output_buf)

+{

+  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;

+  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;

+  JDIMENSION block_num, last_block_column;

+  int ci, block_row, block_rows, access_rows;

+  JBLOCKARRAY buffer;

+  JBLOCKROW buffer_ptr, prev_block_row, next_block_row;

+  JSAMPARRAY output_ptr;

+  JDIMENSION output_col;

+  jpeg_component_info *compptr;

+  inverse_DCT_method_ptr inverse_DCT;

+  boolean first_row, last_row;

+  JBLOCK workspace;

+  int *coef_bits;

+  JQUANT_TBL *quanttbl;

+  INT32 Q00,Q01,Q02,Q10,Q11,Q20, num;

+  int DC1,DC2,DC3,DC4,DC5,DC6,DC7,DC8,DC9;

+  int Al, pred;

+

+  /* Force some input to be done if we are getting ahead of the input. */

+  while (cinfo->input_scan_number <= cinfo->output_scan_number &&

+	 ! cinfo->inputctl->eoi_reached) {

+    if (cinfo->input_scan_number == cinfo->output_scan_number) {

+      /* If input is working on current scan, we ordinarily want it to

+       * have completed the current row.  But if input scan is DC,

+       * we want it to keep one row ahead so that next block row's DC

+       * values are up to date.

+       */

+      JDIMENSION delta = (cinfo->Ss == 0) ? 1 : 0;

+      if (cinfo->input_iMCU_row > cinfo->output_iMCU_row+delta)

+	break;

+    }

+    if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED)

+      return JPEG_SUSPENDED;

+  }

+

+  /* OK, output from the virtual arrays. */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Don't bother to IDCT an uninteresting component. */

+    if (! compptr->component_needed)

+      continue;

+    /* Count non-dummy DCT block rows in this iMCU row. */

+    if (cinfo->output_iMCU_row < last_iMCU_row) {

+      block_rows = compptr->v_samp_factor;

+      access_rows = block_rows * 2; /* this and next iMCU row */

+      last_row = FALSE;

+    } else {

+      /* NB: can't use last_row_height here; it is input-side-dependent! */

+      block_rows = (int) (compptr->height_in_blocks % compptr->v_samp_factor);

+      if (block_rows == 0) block_rows = compptr->v_samp_factor;

+      access_rows = block_rows; /* this iMCU row only */

+      last_row = TRUE;

+    }

+    /* Align the virtual buffer for this component. */

+    if (cinfo->output_iMCU_row > 0) {

+      access_rows += compptr->v_samp_factor; /* prior iMCU row too */

+      buffer = (*cinfo->mem->access_virt_barray)

+	((j_common_ptr) cinfo, coef->whole_image[ci],

+	 (cinfo->output_iMCU_row - 1) * compptr->v_samp_factor,

+	 (JDIMENSION) access_rows, FALSE);

+      buffer += compptr->v_samp_factor;	/* point to current iMCU row */

+      first_row = FALSE;

+    } else {

+      buffer = (*cinfo->mem->access_virt_barray)

+	((j_common_ptr) cinfo, coef->whole_image[ci],

+	 (JDIMENSION) 0, (JDIMENSION) access_rows, FALSE);

+      first_row = TRUE;

+    }

+    /* Fetch component-dependent info */

+    coef_bits = coef->coef_bits_latch + (ci * SAVED_COEFS);

+    quanttbl = compptr->quant_table;

+    Q00 = quanttbl->quantval[0];

+    Q01 = quanttbl->quantval[1];

+    Q10 = quanttbl->quantval[2];

+    Q20 = quanttbl->quantval[3];

+    Q11 = quanttbl->quantval[4];

+    Q02 = quanttbl->quantval[5];

+    inverse_DCT = cinfo->idct->inverse_DCT[ci];

+    output_ptr = output_buf[ci];

+    /* Loop over all DCT blocks to be processed. */

+    for (block_row = 0; block_row < block_rows; block_row++) {

+      buffer_ptr = buffer[block_row];

+      if (first_row && block_row == 0)

+	prev_block_row = buffer_ptr;

+      else

+	prev_block_row = buffer[block_row-1];

+      if (last_row && block_row == block_rows-1)

+	next_block_row = buffer_ptr;

+      else

+	next_block_row = buffer[block_row+1];

+      /* We fetch the surrounding DC values using a sliding-register approach.

+       * Initialize all nine here so as to do the right thing on narrow pics.

+       */

+      DC1 = DC2 = DC3 = (int) prev_block_row[0][0];

+      DC4 = DC5 = DC6 = (int) buffer_ptr[0][0];

+      DC7 = DC8 = DC9 = (int) next_block_row[0][0];

+      output_col = 0;

+      last_block_column = compptr->width_in_blocks - 1;

+      for (block_num = 0; block_num <= last_block_column; block_num++) {

+	/* Fetch current DCT block into workspace so we can modify it. */

+	jcopy_block_row(buffer_ptr, (JBLOCKROW) workspace, (JDIMENSION) 1);

+	/* Update DC values */

+	if (block_num < last_block_column) {

+	  DC3 = (int) prev_block_row[1][0];

+	  DC6 = (int) buffer_ptr[1][0];

+	  DC9 = (int) next_block_row[1][0];

+	}

+	/* Compute coefficient estimates per K.8.

+	 * An estimate is applied only if coefficient is still zero,

+	 * and is not known to be fully accurate.

+	 */

+	/* AC01 */

+	if ((Al=coef_bits[1]) != 0 && workspace[1] == 0) {

+	  num = 36 * Q00 * (DC4 - DC6);

+	  if (num >= 0) {

+	    pred = (int) (((Q01<<7) + num) / (Q01<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	  } else {

+	    pred = (int) (((Q01<<7) - num) / (Q01<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	    pred = -pred;

+	  }

+	  workspace[1] = (JCOEF) pred;

+	}

+	/* AC10 */

+	if ((Al=coef_bits[2]) != 0 && workspace[8] == 0) {

+	  num = 36 * Q00 * (DC2 - DC8);

+	  if (num >= 0) {

+	    pred = (int) (((Q10<<7) + num) / (Q10<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	  } else {

+	    pred = (int) (((Q10<<7) - num) / (Q10<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	    pred = -pred;

+	  }

+	  workspace[8] = (JCOEF) pred;

+	}

+	/* AC20 */

+	if ((Al=coef_bits[3]) != 0 && workspace[16] == 0) {

+	  num = 9 * Q00 * (DC2 + DC8 - 2*DC5);

+	  if (num >= 0) {

+	    pred = (int) (((Q20<<7) + num) / (Q20<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	  } else {

+	    pred = (int) (((Q20<<7) - num) / (Q20<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	    pred = -pred;

+	  }

+	  workspace[16] = (JCOEF) pred;

+	}

+	/* AC11 */

+	if ((Al=coef_bits[4]) != 0 && workspace[9] == 0) {

+	  num = 5 * Q00 * (DC1 - DC3 - DC7 + DC9);

+	  if (num >= 0) {

+	    pred = (int) (((Q11<<7) + num) / (Q11<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	  } else {

+	    pred = (int) (((Q11<<7) - num) / (Q11<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	    pred = -pred;

+	  }

+	  workspace[9] = (JCOEF) pred;

+	}

+	/* AC02 */

+	if ((Al=coef_bits[5]) != 0 && workspace[2] == 0) {

+	  num = 9 * Q00 * (DC4 + DC6 - 2*DC5);

+	  if (num >= 0) {

+	    pred = (int) (((Q02<<7) + num) / (Q02<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	  } else {

+	    pred = (int) (((Q02<<7) - num) / (Q02<<8));

+	    if (Al > 0 && pred >= (1<<Al))

+	      pred = (1<<Al)-1;

+	    pred = -pred;

+	  }

+	  workspace[2] = (JCOEF) pred;

+	}

+	/* OK, do the IDCT */

+	(*inverse_DCT) (cinfo, compptr, (JCOEFPTR) workspace,

+			output_ptr, output_col);

+	/* Advance for next column */

+	DC1 = DC2; DC2 = DC3;

+	DC4 = DC5; DC5 = DC6;

+	DC7 = DC8; DC8 = DC9;

+	buffer_ptr++, prev_block_row++, next_block_row++;

+	output_col += compptr->DCT_scaled_size;

+      }

+      output_ptr += compptr->DCT_scaled_size;

+    }

+  }

+

+  if (++(cinfo->output_iMCU_row) < cinfo->total_iMCU_rows)

+    return JPEG_ROW_COMPLETED;

+  return JPEG_SCAN_COMPLETED;

+}

+

+#endif /* BLOCK_SMOOTHING_SUPPORTED */

+

+

+/*

+ * Initialize coefficient buffer controller.

+ */

+

+GLOBAL void

+jinit_d_coef_controller (j_decompress_ptr cinfo, boolean need_full_buffer)

+{

+  my_coef_ptr coef;

+

+  coef = (my_coef_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_coef_controller));

+  cinfo->coef = (struct jpeg_d_coef_controller *) coef;

+  coef->pub.start_input_pass = start_input_pass;

+  coef->pub.start_output_pass = start_output_pass;

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+  coef->coef_bits_latch = NULL;

+#endif

+

+  /* Create the coefficient buffer. */

+  if (need_full_buffer) {

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+    /* Allocate a full-image virtual array for each component, */

+    /* padded to a multiple of samp_factor DCT blocks in each direction. */

+    /* Note we ask for a pre-zeroed array. */

+    int ci, access_rows;

+    jpeg_component_info *compptr;

+

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      access_rows = compptr->v_samp_factor;

+#ifdef BLOCK_SMOOTHING_SUPPORTED

+      /* If block smoothing could be used, need a bigger window */

+      if (cinfo->progressive_mode)

+	access_rows *= 3;

+#endif

+      coef->whole_image[ci] = (*cinfo->mem->request_virt_barray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE, TRUE,

+	 (JDIMENSION) jround_up((long) compptr->width_in_blocks,

+				(long) compptr->h_samp_factor),

+	 (JDIMENSION) jround_up((long) compptr->height_in_blocks,

+				(long) compptr->v_samp_factor),

+	 (JDIMENSION) access_rows);

+    }

+    coef->pub.consume_data = consume_data;

+    coef->pub.decompress_data = decompress_data;

+    coef->pub.coef_arrays = coef->whole_image; /* link to virtual arrays */

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+  } else {

+    /* We only need a single-MCU buffer. */

+    JBLOCKROW buffer;

+    int i;

+

+    buffer = (JBLOCKROW)

+      (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  D_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));

+    for (i = 0; i < D_MAX_BLOCKS_IN_MCU; i++) {

+      coef->MCU_buffer[i] = buffer + i;

+    }

+    coef->pub.consume_data = dummy_consume_data;

+    coef->pub.decompress_data = decompress_onepass;

+    coef->pub.coef_arrays = NULL; /* flag for no virtual arrays */

+  }

+}

diff --git a/code/jpeg-6/jdcolor.c b/code/jpeg-6/jdcolor.c
new file mode 100755
index 0000000..d360b53
--- /dev/null
+++ b/code/jpeg-6/jdcolor.c
@@ -0,0 +1,367 @@
+/*

+ * jdcolor.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains output colorspace conversion routines.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_color_deconverter pub; /* public fields */

+

+  /* Private state for YCC->RGB conversion */

+  int * Cr_r_tab;		/* => table for Cr to R conversion */

+  int * Cb_b_tab;		/* => table for Cb to B conversion */

+  INT32 * Cr_g_tab;		/* => table for Cr to G conversion */

+  INT32 * Cb_g_tab;		/* => table for Cb to G conversion */

+} my_color_deconverter;

+

+typedef my_color_deconverter * my_cconvert_ptr;

+

+

+/**************** YCbCr -> RGB conversion: most common case **************/

+

+/*

+ * YCbCr is defined per CCIR 601-1, except that Cb and Cr are

+ * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5.

+ * The conversion equations to be implemented are therefore

+ *	R = Y                + 1.40200 * Cr

+ *	G = Y - 0.34414 * Cb - 0.71414 * Cr

+ *	B = Y + 1.77200 * Cb

+ * where Cb and Cr represent the incoming values less CENTERJSAMPLE.

+ * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.)

+ *

+ * To avoid floating-point arithmetic, we represent the fractional constants

+ * as integers scaled up by 2^16 (about 4 digits precision); we have to divide

+ * the products by 2^16, with appropriate rounding, to get the correct answer.

+ * Notice that Y, being an integral input, does not contribute any fraction

+ * so it need not participate in the rounding.

+ *

+ * For even more speed, we avoid doing any multiplications in the inner loop

+ * by precalculating the constants times Cb and Cr for all possible values.

+ * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table);

+ * for 12-bit samples it is still acceptable.  It's not very reasonable for

+ * 16-bit samples, but if you want lossless storage you shouldn't be changing

+ * colorspace anyway.

+ * The Cr=>R and Cb=>B values can be rounded to integers in advance; the

+ * values for the G calculation are left scaled up, since we must add them

+ * together before rounding.

+ */

+

+#define SCALEBITS	16	/* speediest right-shift on some machines */

+#define ONE_HALF	((INT32) 1 << (SCALEBITS-1))

+#define FIX(x)		((INT32) ((x) * (1L<<SCALEBITS) + 0.5))

+

+

+/*

+ * Initialize tables for YCC->RGB colorspace conversion.

+ */

+

+LOCAL void

+build_ycc_rgb_table (j_decompress_ptr cinfo)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  int i;

+  INT32 x;

+  SHIFT_TEMPS

+

+  cconvert->Cr_r_tab = (int *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(int));

+  cconvert->Cb_b_tab = (int *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(int));

+  cconvert->Cr_g_tab = (INT32 *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(INT32));

+  cconvert->Cb_g_tab = (INT32 *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(INT32));

+

+  for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {

+    /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */

+    /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */

+    /* Cr=>R value is nearest int to 1.40200 * x */

+    cconvert->Cr_r_tab[i] = (int)

+		    RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);

+    /* Cb=>B value is nearest int to 1.77200 * x */

+    cconvert->Cb_b_tab[i] = (int)

+		    RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);

+    /* Cr=>G value is scaled-up -0.71414 * x */

+    cconvert->Cr_g_tab[i] = (- FIX(0.71414)) * x;

+    /* Cb=>G value is scaled-up -0.34414 * x */

+    /* We also add in ONE_HALF so that need not do it in inner loop */

+    cconvert->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;

+  }

+}

+

+

+/*

+ * Convert some rows of samples to the output colorspace.

+ *

+ * Note that we change from noninterleaved, one-plane-per-component format

+ * to interleaved-pixel format.  The output buffer is therefore three times

+ * as wide as the input buffer.

+ * A starting row offset is provided only for the input buffer.  The caller

+ * can easily adjust the passed output_buf value to accommodate any row

+ * offset required on that side.

+ */

+

+METHODDEF void

+ycc_rgb_convert (j_decompress_ptr cinfo,

+		 JSAMPIMAGE input_buf, JDIMENSION input_row,

+		 JSAMPARRAY output_buf, int num_rows)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  register int y, cb, cr;

+  register JSAMPROW outptr;

+  register JSAMPROW inptr0, inptr1, inptr2;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->output_width;

+  /* copy these pointers into registers if possible */

+  register JSAMPLE * range_limit = cinfo->sample_range_limit;

+  register int * Crrtab = cconvert->Cr_r_tab;

+  register int * Cbbtab = cconvert->Cb_b_tab;

+  register INT32 * Crgtab = cconvert->Cr_g_tab;

+  register INT32 * Cbgtab = cconvert->Cb_g_tab;

+  SHIFT_TEMPS

+

+  while (--num_rows >= 0) {

+    inptr0 = input_buf[0][input_row];

+    inptr1 = input_buf[1][input_row];

+    inptr2 = input_buf[2][input_row];

+    input_row++;

+    outptr = *output_buf++;

+    for (col = 0; col < num_cols; col++) {

+      y  = GETJSAMPLE(inptr0[col]);

+      cb = GETJSAMPLE(inptr1[col]);

+      cr = GETJSAMPLE(inptr2[col]);

+      /* Range-limiting is essential due to noise introduced by DCT losses. */

+      outptr[RGB_RED] =   range_limit[y + Crrtab[cr]];

+      outptr[RGB_GREEN] = range_limit[y +

+			      ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],

+						 SCALEBITS))];

+      outptr[RGB_BLUE] =  range_limit[y + Cbbtab[cb]];

+      outptr += RGB_PIXELSIZE;

+    }

+  }

+}

+

+

+/**************** Cases other than YCbCr -> RGB **************/

+

+

+/*

+ * Color conversion for no colorspace change: just copy the data,

+ * converting from separate-planes to interleaved representation.

+ */

+

+METHODDEF void

+null_convert (j_decompress_ptr cinfo,

+	      JSAMPIMAGE input_buf, JDIMENSION input_row,

+	      JSAMPARRAY output_buf, int num_rows)

+{

+  register JSAMPROW inptr, outptr;

+  register JDIMENSION count;

+  register int num_components = cinfo->num_components;

+  JDIMENSION num_cols = cinfo->output_width;

+  int ci;

+

+  while (--num_rows >= 0) {

+    for (ci = 0; ci < num_components; ci++) {

+      inptr = input_buf[ci][input_row];

+      outptr = output_buf[0] + ci;

+      for (count = num_cols; count > 0; count--) {

+	*outptr = *inptr++;	/* needn't bother with GETJSAMPLE() here */

+	outptr += num_components;

+      }

+    }

+    input_row++;

+    output_buf++;

+  }

+}

+

+

+/*

+ * Color conversion for grayscale: just copy the data.

+ * This also works for YCbCr -> grayscale conversion, in which

+ * we just copy the Y (luminance) component and ignore chrominance.

+ */

+

+METHODDEF void

+grayscale_convert (j_decompress_ptr cinfo,

+		   JSAMPIMAGE input_buf, JDIMENSION input_row,

+		   JSAMPARRAY output_buf, int num_rows)

+{

+  jcopy_sample_rows(input_buf[0], (int) input_row, output_buf, 0,

+		    num_rows, cinfo->output_width);

+}

+

+

+/*

+ * Adobe-style YCCK->CMYK conversion.

+ * We convert YCbCr to R=1-C, G=1-M, and B=1-Y using the same

+ * conversion as above, while passing K (black) unchanged.

+ * We assume build_ycc_rgb_table has been called.

+ */

+

+METHODDEF void

+ycck_cmyk_convert (j_decompress_ptr cinfo,

+		   JSAMPIMAGE input_buf, JDIMENSION input_row,

+		   JSAMPARRAY output_buf, int num_rows)

+{

+  my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;

+  register int y, cb, cr;

+  register JSAMPROW outptr;

+  register JSAMPROW inptr0, inptr1, inptr2, inptr3;

+  register JDIMENSION col;

+  JDIMENSION num_cols = cinfo->output_width;

+  /* copy these pointers into registers if possible */

+  register JSAMPLE * range_limit = cinfo->sample_range_limit;

+  register int * Crrtab = cconvert->Cr_r_tab;

+  register int * Cbbtab = cconvert->Cb_b_tab;

+  register INT32 * Crgtab = cconvert->Cr_g_tab;

+  register INT32 * Cbgtab = cconvert->Cb_g_tab;

+  SHIFT_TEMPS

+

+  while (--num_rows >= 0) {

+    inptr0 = input_buf[0][input_row];

+    inptr1 = input_buf[1][input_row];

+    inptr2 = input_buf[2][input_row];

+    inptr3 = input_buf[3][input_row];

+    input_row++;

+    outptr = *output_buf++;

+    for (col = 0; col < num_cols; col++) {

+      y  = GETJSAMPLE(inptr0[col]);

+      cb = GETJSAMPLE(inptr1[col]);

+      cr = GETJSAMPLE(inptr2[col]);

+      /* Range-limiting is essential due to noise introduced by DCT losses. */

+      outptr[0] = range_limit[MAXJSAMPLE - (y + Crrtab[cr])];	/* red */

+      outptr[1] = range_limit[MAXJSAMPLE - (y +			/* green */

+			      ((int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr],

+						 SCALEBITS)))];

+      outptr[2] = range_limit[MAXJSAMPLE - (y + Cbbtab[cb])];	/* blue */

+      /* K passes through unchanged */

+      outptr[3] = inptr3[col];	/* don't need GETJSAMPLE here */

+      outptr += 4;

+    }

+  }

+}

+

+

+/*

+ * Empty method for start_pass.

+ */

+

+METHODDEF void

+start_pass_dcolor (j_decompress_ptr cinfo)

+{

+  /* no work needed */

+}

+

+

+/*

+ * Module initialization routine for output colorspace conversion.

+ */

+

+GLOBAL void

+jinit_color_deconverter (j_decompress_ptr cinfo)

+{

+  my_cconvert_ptr cconvert;

+  int ci;

+

+  cconvert = (my_cconvert_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_color_deconverter));

+  cinfo->cconvert = (struct jpeg_color_deconverter *) cconvert;

+  cconvert->pub.start_pass = start_pass_dcolor;

+

+  /* Make sure num_components agrees with jpeg_color_space */

+  switch (cinfo->jpeg_color_space) {

+  case JCS_GRAYSCALE:

+    if (cinfo->num_components != 1)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    break;

+

+  case JCS_RGB:

+  case JCS_YCbCr:

+    if (cinfo->num_components != 3)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    break;

+

+  case JCS_CMYK:

+  case JCS_YCCK:

+    if (cinfo->num_components != 4)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    break;

+

+  default:			/* JCS_UNKNOWN can be anything */

+    if (cinfo->num_components < 1)

+      ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

+    break;

+  }

+

+  /* Set out_color_components and conversion method based on requested space.

+   * Also clear the component_needed flags for any unused components,

+   * so that earlier pipeline stages can avoid useless computation.

+   */

+

+  switch (cinfo->out_color_space) {

+  case JCS_GRAYSCALE:

+    cinfo->out_color_components = 1;

+    if (cinfo->jpeg_color_space == JCS_GRAYSCALE ||

+	cinfo->jpeg_color_space == JCS_YCbCr) {

+      cconvert->pub.color_convert = grayscale_convert;

+      /* For color->grayscale conversion, only the Y (0) component is needed */

+      for (ci = 1; ci < cinfo->num_components; ci++)

+	cinfo->comp_info[ci].component_needed = FALSE;

+    } else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_RGB:

+    cinfo->out_color_components = RGB_PIXELSIZE;

+    if (cinfo->jpeg_color_space == JCS_YCbCr) {

+      cconvert->pub.color_convert = ycc_rgb_convert;

+      build_ycc_rgb_table(cinfo);

+    } else if (cinfo->jpeg_color_space == JCS_RGB && RGB_PIXELSIZE == 3) {

+      cconvert->pub.color_convert = null_convert;

+    } else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  case JCS_CMYK:

+    cinfo->out_color_components = 4;

+    if (cinfo->jpeg_color_space == JCS_YCCK) {

+      cconvert->pub.color_convert = ycck_cmyk_convert;

+      build_ycc_rgb_table(cinfo);

+    } else if (cinfo->jpeg_color_space == JCS_CMYK) {

+      cconvert->pub.color_convert = null_convert;

+    } else

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+

+  default:

+    /* Permit null conversion to same output space */

+    if (cinfo->out_color_space == cinfo->jpeg_color_space) {

+      cinfo->out_color_components = cinfo->num_components;

+      cconvert->pub.color_convert = null_convert;

+    } else			/* unsupported non-null conversion */

+      ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);

+    break;

+  }

+

+  if (cinfo->quantize_colors)

+    cinfo->output_components = 1; /* single colormapped output component */

+  else

+    cinfo->output_components = cinfo->out_color_components;

+}

diff --git a/code/jpeg-6/jdct.h b/code/jpeg-6/jdct.h
new file mode 100755
index 0000000..1d66d4f
--- /dev/null
+++ b/code/jpeg-6/jdct.h
@@ -0,0 +1,176 @@
+/*

+ * jdct.h

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This include file contains common declarations for the forward and

+ * inverse DCT modules.  These declarations are private to the DCT managers

+ * (jcdctmgr.c, jddctmgr.c) and the individual DCT algorithms.

+ * The individual DCT algorithms are kept in separate files to ease 

+ * machine-dependent tuning (e.g., assembly coding).

+ */

+

+

+/*

+ * A forward DCT routine is given a pointer to a work area of type DCTELEM[];

+ * the DCT is to be performed in-place in that buffer.  Type DCTELEM is int

+ * for 8-bit samples, INT32 for 12-bit samples.  (NOTE: Floating-point DCT

+ * implementations use an array of type FAST_FLOAT, instead.)

+ * The DCT inputs are expected to be signed (range +-CENTERJSAMPLE).

+ * The DCT outputs are returned scaled up by a factor of 8; they therefore

+ * have a range of +-8K for 8-bit data, +-128K for 12-bit data.  This

+ * convention improves accuracy in integer implementations and saves some

+ * work in floating-point ones.

+ * Quantization of the output coefficients is done by jcdctmgr.c.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+typedef int DCTELEM;		/* 16 or 32 bits is fine */

+#else

+typedef INT32 DCTELEM;		/* must have 32 bits */

+#endif

+

+typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data));

+typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data));

+

+

+/*

+ * An inverse DCT routine is given a pointer to the input JBLOCK and a pointer

+ * to an output sample array.  The routine must dequantize the input data as

+ * well as perform the IDCT; for dequantization, it uses the multiplier table

+ * pointed to by compptr->dct_table.  The output data is to be placed into the

+ * sample array starting at a specified column.  (Any row offset needed will

+ * be applied to the array pointer before it is passed to the IDCT code.)

+ * Note that the number of samples emitted by the IDCT routine is

+ * DCT_scaled_size * DCT_scaled_size.

+ */

+

+/* typedef inverse_DCT_method_ptr is declared in jpegint.h */

+

+/*

+ * Each IDCT routine has its own ideas about the best dct_table element type.

+ */

+

+typedef MULTIPLIER ISLOW_MULT_TYPE; /* short or int, whichever is faster */

+#if BITS_IN_JSAMPLE == 8

+typedef MULTIPLIER IFAST_MULT_TYPE; /* 16 bits is OK, use short if faster */

+#define IFAST_SCALE_BITS  2	/* fractional bits in scale factors */

+#else

+typedef INT32 IFAST_MULT_TYPE;	/* need 32 bits for scaled quantizers */

+#define IFAST_SCALE_BITS  13	/* fractional bits in scale factors */

+#endif

+typedef FAST_FLOAT FLOAT_MULT_TYPE; /* preferred floating type */

+

+

+/*

+ * Each IDCT routine is responsible for range-limiting its results and

+ * converting them to unsigned form (0..MAXJSAMPLE).  The raw outputs could

+ * be quite far out of range if the input data is corrupt, so a bulletproof

+ * range-limiting step is required.  We use a mask-and-table-lookup method

+ * to do the combined operations quickly.  See the comments with

+ * prepare_range_limit_table (in jdmaster.c) for more info.

+ */

+

+#define IDCT_range_limit(cinfo)  ((cinfo)->sample_range_limit + CENTERJSAMPLE)

+

+#define RANGE_MASK  (MAXJSAMPLE * 4 + 3) /* 2 bits wider than legal samples */

+

+

+/* Short forms of external names for systems with brain-damaged linkers. */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_fdct_islow		jFDislow

+#define jpeg_fdct_ifast		jFDifast

+#define jpeg_fdct_float		jFDfloat

+#define jpeg_idct_islow		jRDislow

+#define jpeg_idct_ifast		jRDifast

+#define jpeg_idct_float		jRDfloat

+#define jpeg_idct_4x4		jRD4x4

+#define jpeg_idct_2x2		jRD2x2

+#define jpeg_idct_1x1		jRD1x1

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+/* Extern declarations for the forward and inverse DCT routines. */

+

+EXTERN void jpeg_fdct_islow JPP((DCTELEM * data));

+EXTERN void jpeg_fdct_ifast JPP((DCTELEM * data));

+EXTERN void jpeg_fdct_float JPP((FAST_FLOAT * data));

+

+EXTERN void jpeg_idct_islow

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+EXTERN void jpeg_idct_ifast

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+EXTERN void jpeg_idct_float

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+EXTERN void jpeg_idct_4x4

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+EXTERN void jpeg_idct_2x2

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+EXTERN void jpeg_idct_1x1

+    JPP((j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	 JCOEFPTR coef_block, JSAMPARRAY output_buf, JDIMENSION output_col));

+

+

+/*

+ * Macros for handling fixed-point arithmetic; these are used by many

+ * but not all of the DCT/IDCT modules.

+ *

+ * All values are expected to be of type INT32.

+ * Fractional constants are scaled left by CONST_BITS bits.

+ * CONST_BITS is defined within each module using these macros,

+ * and may differ from one module to the next.

+ */

+

+#define ONE	((INT32) 1)

+#define CONST_SCALE (ONE << CONST_BITS)

+

+/* Convert a positive real constant to an integer scaled by CONST_SCALE.

+ * Caution: some C compilers fail to reduce "FIX(constant)" at compile time,

+ * thus causing a lot of useless floating-point operations at run time.

+ */

+

+#define FIX(x)	((INT32) ((x) * CONST_SCALE + 0.5))

+

+/* Descale and correctly round an INT32 value that's scaled by N bits.

+ * We assume RIGHT_SHIFT rounds towards minus infinity, so adding

+ * the fudge factor is correct for either sign of X.

+ */

+

+#define DESCALE(x,n)  RIGHT_SHIFT((x) + (ONE << ((n)-1)), n)

+

+/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.

+ * This macro is used only when the two inputs will actually be no more than

+ * 16 bits wide, so that a 16x16->32 bit multiply can be used instead of a

+ * full 32x32 multiply.  This provides a useful speedup on many machines.

+ * Unfortunately there is no way to specify a 16x16->32 multiply portably

+ * in C, but some C compilers will do the right thing if you provide the

+ * correct combination of casts.

+ */

+

+#ifdef SHORTxSHORT_32		/* may work if 'int' is 32 bits */

+#define MULTIPLY16C16(var,const)  (((INT16) (var)) * ((INT16) (const)))

+#endif

+#ifdef SHORTxLCONST_32		/* known to work with Microsoft C 6.0 */

+#define MULTIPLY16C16(var,const)  (((INT16) (var)) * ((INT32) (const)))

+#endif

+

+#ifndef MULTIPLY16C16		/* default definition */

+#define MULTIPLY16C16(var,const)  ((var) * (const))

+#endif

+

+/* Same except both inputs are variables. */

+

+#ifdef SHORTxSHORT_32		/* may work if 'int' is 32 bits */

+#define MULTIPLY16V16(var1,var2)  (((INT16) (var1)) * ((INT16) (var2)))

+#endif

+

+#ifndef MULTIPLY16V16		/* default definition */

+#define MULTIPLY16V16(var1,var2)  ((var1) * (var2))

+#endif

diff --git a/code/jpeg-6/jddctmgr.c b/code/jpeg-6/jddctmgr.c
new file mode 100755
index 0000000..ba01fc6
--- /dev/null
+++ b/code/jpeg-6/jddctmgr.c
@@ -0,0 +1,270 @@
+/*

+ * jddctmgr.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the inverse-DCT management logic.

+ * This code selects a particular IDCT implementation to be used,

+ * and it performs related housekeeping chores.  No code in this file

+ * is executed per IDCT step, only during output pass setup.

+ *

+ * Note that the IDCT routines are responsible for performing coefficient

+ * dequantization as well as the IDCT proper.  This module sets up the

+ * dequantization multiplier table needed by the IDCT routine.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+

+/*

+ * The decompressor input side (jdinput.c) saves away the appropriate

+ * quantization table for each component at the start of the first scan

+ * involving that component.  (This is necessary in order to correctly

+ * decode files that reuse Q-table slots.)

+ * When we are ready to make an output pass, the saved Q-table is converted

+ * to a multiplier table that will actually be used by the IDCT routine.

+ * The multiplier table contents are IDCT-method-dependent.  To support

+ * application changes in IDCT method between scans, we can remake the

+ * multiplier tables if necessary.

+ * In buffered-image mode, the first output pass may occur before any data

+ * has been seen for some components, and thus before their Q-tables have

+ * been saved away.  To handle this case, multiplier tables are preset

+ * to zeroes; the result of the IDCT will be a neutral gray level.

+ */

+

+

+/* Private subobject for this module */

+

+typedef struct {

+  struct jpeg_inverse_dct pub;	/* public fields */

+

+  /* This array contains the IDCT method code that each multiplier table

+   * is currently set up for, or -1 if it's not yet set up.

+   * The actual multiplier tables are pointed to by dct_table in the

+   * per-component comp_info structures.

+   */

+  int cur_method[MAX_COMPONENTS];

+} my_idct_controller;

+

+typedef my_idct_controller * my_idct_ptr;

+

+

+/* Allocated multiplier tables: big enough for any supported variant */

+

+typedef union {

+  ISLOW_MULT_TYPE islow_array[DCTSIZE2];

+#ifdef DCT_IFAST_SUPPORTED

+  IFAST_MULT_TYPE ifast_array[DCTSIZE2];

+#endif

+#ifdef DCT_FLOAT_SUPPORTED

+  FLOAT_MULT_TYPE float_array[DCTSIZE2];

+#endif

+} multiplier_table;

+

+

+/* The current scaled-IDCT routines require ISLOW-style multiplier tables,

+ * so be sure to compile that code if either ISLOW or SCALING is requested.

+ */

+#ifdef DCT_ISLOW_SUPPORTED

+#define PROVIDE_ISLOW_TABLES

+#else

+#ifdef IDCT_SCALING_SUPPORTED

+#define PROVIDE_ISLOW_TABLES

+#endif

+#endif

+

+

+/*

+ * Prepare for an output pass.

+ * Here we select the proper IDCT routine for each component and build

+ * a matching multiplier table.

+ */

+

+METHODDEF void

+start_pass (j_decompress_ptr cinfo)

+{

+  my_idct_ptr idct = (my_idct_ptr) cinfo->idct;

+  int ci, i;

+  jpeg_component_info *compptr;

+  int method = 0;

+  inverse_DCT_method_ptr method_ptr = NULL;

+  JQUANT_TBL * qtbl;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Select the proper IDCT routine for this component's scaling */

+    switch (compptr->DCT_scaled_size) {

+#ifdef IDCT_SCALING_SUPPORTED

+    case 1:

+      method_ptr = jpeg_idct_1x1;

+      method = JDCT_ISLOW;	/* jidctred uses islow-style table */

+      break;

+    case 2:

+      method_ptr = jpeg_idct_2x2;

+      method = JDCT_ISLOW;	/* jidctred uses islow-style table */

+      break;

+    case 4:

+      method_ptr = jpeg_idct_4x4;

+      method = JDCT_ISLOW;	/* jidctred uses islow-style table */

+      break;

+#endif

+    case DCTSIZE:

+      switch (cinfo->dct_method) {

+#ifdef DCT_ISLOW_SUPPORTED

+      case JDCT_ISLOW:

+	method_ptr = jpeg_idct_islow;

+	method = JDCT_ISLOW;

+	break;

+#endif

+#ifdef DCT_IFAST_SUPPORTED

+      case JDCT_IFAST:

+	method_ptr = jpeg_idct_ifast;

+	method = JDCT_IFAST;

+	break;

+#endif

+#ifdef DCT_FLOAT_SUPPORTED

+      case JDCT_FLOAT:

+	method_ptr = jpeg_idct_float;

+	method = JDCT_FLOAT;

+	break;

+#endif

+      default:

+	ERREXIT(cinfo, JERR_NOT_COMPILED);

+	break;

+      }

+      break;

+    default:

+      ERREXIT1(cinfo, JERR_BAD_DCTSIZE, compptr->DCT_scaled_size);

+      break;

+    }

+    idct->pub.inverse_DCT[ci] = method_ptr;

+    /* Create multiplier table from quant table.

+     * However, we can skip this if the component is uninteresting

+     * or if we already built the table.  Also, if no quant table

+     * has yet been saved for the component, we leave the

+     * multiplier table all-zero; we'll be reading zeroes from the

+     * coefficient controller's buffer anyway.

+     */

+    if (! compptr->component_needed || idct->cur_method[ci] == method)

+      continue;

+    qtbl = compptr->quant_table;

+    if (qtbl == NULL)		/* happens if no data yet for component */

+      continue;

+    idct->cur_method[ci] = method;

+    switch (method) {

+#ifdef PROVIDE_ISLOW_TABLES

+    case JDCT_ISLOW:

+      {

+	/* For LL&M IDCT method, multipliers are equal to raw quantization

+	 * coefficients, but are stored in natural order as ints.

+	 */

+	ISLOW_MULT_TYPE * ismtbl = (ISLOW_MULT_TYPE *) compptr->dct_table;

+	for (i = 0; i < DCTSIZE2; i++) {

+	  ismtbl[i] = (ISLOW_MULT_TYPE) qtbl->quantval[jpeg_zigzag_order[i]];

+	}

+      }

+      break;

+#endif

+#ifdef DCT_IFAST_SUPPORTED

+    case JDCT_IFAST:

+      {

+	/* For AA&N IDCT method, multipliers are equal to quantization

+	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

+	 *   scalefactor[0] = 1

+	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

+	 * For integer operation, the multiplier table is to be scaled by

+	 * IFAST_SCALE_BITS.  The multipliers are stored in natural order.

+	 */

+	IFAST_MULT_TYPE * ifmtbl = (IFAST_MULT_TYPE *) compptr->dct_table;

+#define CONST_BITS 14

+	static const INT16 aanscales[DCTSIZE2] = {

+	  /* precomputed values scaled up by 14 bits */

+	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

+	  22725, 31521, 29692, 26722, 22725, 17855, 12299,  6270,

+	  21407, 29692, 27969, 25172, 21407, 16819, 11585,  5906,

+	  19266, 26722, 25172, 22654, 19266, 15137, 10426,  5315,

+	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

+	  12873, 17855, 16819, 15137, 12873, 10114,  6967,  3552,

+	   8867, 12299, 11585, 10426,  8867,  6967,  4799,  2446,

+	   4520,  6270,  5906,  5315,  4520,  3552,  2446,  1247

+	};

+	SHIFT_TEMPS

+

+	for (i = 0; i < DCTSIZE2; i++) {

+	  ifmtbl[i] = (IFAST_MULT_TYPE)

+	    DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[jpeg_zigzag_order[i]],

+				  (INT32) aanscales[i]),

+		    CONST_BITS-IFAST_SCALE_BITS);

+	}

+      }

+      break;

+#endif

+#ifdef DCT_FLOAT_SUPPORTED

+    case JDCT_FLOAT:

+      {

+	/* For float AA&N IDCT method, multipliers are equal to quantization

+	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

+	 *   scalefactor[0] = 1

+	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

+	 * The multipliers are stored in natural order.

+	 */

+	FLOAT_MULT_TYPE * fmtbl = (FLOAT_MULT_TYPE *) compptr->dct_table;

+	int row, col;

+	static const double aanscalefactor[DCTSIZE] = {

+	  1.0, 1.387039845, 1.306562965, 1.175875602,

+	  1.0, 0.785694958, 0.541196100, 0.275899379

+	};

+

+	i = 0;

+	for (row = 0; row < DCTSIZE; row++) {

+	  for (col = 0; col < DCTSIZE; col++) {

+	    fmtbl[i] = (FLOAT_MULT_TYPE)

+	      ((double) qtbl->quantval[jpeg_zigzag_order[i]] *

+	       aanscalefactor[row] * aanscalefactor[col]);

+	    i++;

+	  }

+	}

+      }

+      break;

+#endif

+    default:

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+      break;

+    }

+  }

+}

+

+

+/*

+ * Initialize IDCT manager.

+ */

+

+GLOBAL void

+jinit_inverse_dct (j_decompress_ptr cinfo)

+{

+  my_idct_ptr idct;

+  int ci;

+  jpeg_component_info *compptr;

+

+  idct = (my_idct_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_idct_controller));

+  cinfo->idct = (struct jpeg_inverse_dct *) idct;

+  idct->pub.start_pass = start_pass;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Allocate and pre-zero a multiplier table for each component */

+    compptr->dct_table =

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(multiplier_table));

+    MEMZERO(compptr->dct_table, SIZEOF(multiplier_table));

+    /* Mark multiplier table not yet set up for any method */

+    idct->cur_method[ci] = -1;

+  }

+}

diff --git a/code/jpeg-6/jdhuff.c b/code/jpeg-6/jdhuff.c
new file mode 100755
index 0000000..db42772
--- /dev/null
+++ b/code/jpeg-6/jdhuff.c
@@ -0,0 +1,574 @@
+/*

+ * jdhuff.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains Huffman entropy decoding routines.

+ *

+ * Much of the complexity here has to do with supporting input suspension.

+ * If the data source module demands suspension, we want to be able to back

+ * up to the start of the current MCU.  To do this, we copy state variables

+ * into local working storage, and update them back to the permanent

+ * storage only upon successful completion of an MCU.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdhuff.h"		/* Declarations shared with jdphuff.c */

+

+

+/*

+ * Expanded entropy decoder object for Huffman decoding.

+ *

+ * The savable_state subrecord contains fields that change within an MCU,

+ * but must not be updated permanently until we complete the MCU.

+ */

+

+typedef struct {

+  int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */

+} savable_state;

+

+/* This macro is to work around compilers with missing or broken

+ * structure assignment.  You'll need to fix this code if you have

+ * such a compiler and you change MAX_COMPS_IN_SCAN.

+ */

+

+#ifndef NO_STRUCT_ASSIGN

+#define ASSIGN_STATE(dest,src)  ((dest) = (src))

+#else

+#if MAX_COMPS_IN_SCAN == 4

+#define ASSIGN_STATE(dest,src)  \

+	((dest).last_dc_val[0] = (src).last_dc_val[0], \

+	 (dest).last_dc_val[1] = (src).last_dc_val[1], \

+	 (dest).last_dc_val[2] = (src).last_dc_val[2], \

+	 (dest).last_dc_val[3] = (src).last_dc_val[3])

+#endif

+#endif

+

+

+typedef struct {

+  struct jpeg_entropy_decoder pub; /* public fields */

+

+  /* These fields are loaded into local variables at start of each MCU.

+   * In case of suspension, we exit WITHOUT updating them.

+   */

+  bitread_perm_state bitstate;	/* Bit buffer at start of MCU */

+  savable_state saved;		/* Other state at start of MCU */

+

+  /* These fields are NOT loaded into local working state. */

+  unsigned int restarts_to_go;	/* MCUs left in this restart interval */

+

+  /* Pointers to derived tables (these workspaces have image lifespan) */

+  d_derived_tbl * dc_derived_tbls[NUM_HUFF_TBLS];

+  d_derived_tbl * ac_derived_tbls[NUM_HUFF_TBLS];

+} huff_entropy_decoder;

+

+typedef huff_entropy_decoder * huff_entropy_ptr;

+

+

+/*

+ * Initialize for a Huffman-compressed scan.

+ */

+

+METHODDEF void

+start_pass_huff_decoder (j_decompress_ptr cinfo)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  int ci, dctbl, actbl;

+  jpeg_component_info * compptr;

+

+  /* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG.

+   * This ought to be an error condition, but we make it a warning because

+   * there are some baseline files out there with all zeroes in these bytes.

+   */

+  if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 ||

+      cinfo->Ah != 0 || cinfo->Al != 0)

+    WARNMS(cinfo, JWRN_NOT_SEQUENTIAL);

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    dctbl = compptr->dc_tbl_no;

+    actbl = compptr->ac_tbl_no;

+    /* Make sure requested tables are present */

+    if (dctbl < 0 || dctbl >= NUM_HUFF_TBLS ||

+	cinfo->dc_huff_tbl_ptrs[dctbl] == NULL)

+      ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, dctbl);

+    if (actbl < 0 || actbl >= NUM_HUFF_TBLS ||

+	cinfo->ac_huff_tbl_ptrs[actbl] == NULL)

+      ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, actbl);

+    /* Compute derived values for Huffman tables */

+    /* We may do this more than once for a table, but it's not expensive */

+    jpeg_make_d_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[dctbl],

+			    & entropy->dc_derived_tbls[dctbl]);

+    jpeg_make_d_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[actbl],

+			    & entropy->ac_derived_tbls[actbl]);

+    /* Initialize DC predictions to 0 */

+    entropy->saved.last_dc_val[ci] = 0;

+  }

+

+  /* Initialize bitread state variables */

+  entropy->bitstate.bits_left = 0;

+  entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */

+  entropy->bitstate.printed_eod = FALSE;

+

+  /* Initialize restart counter */

+  entropy->restarts_to_go = cinfo->restart_interval;

+}

+

+

+/*

+ * Compute the derived values for a Huffman table.

+ * Note this is also used by jdphuff.c.

+ */

+

+GLOBAL void

+jpeg_make_d_derived_tbl (j_decompress_ptr cinfo, JHUFF_TBL * htbl,

+			 d_derived_tbl ** pdtbl)

+{

+  d_derived_tbl *dtbl;

+  int p, i, l, si;

+  int lookbits, ctr;

+  char huffsize[257];

+  unsigned int huffcode[257];

+  unsigned int code;

+

+  /* Allocate a workspace if we haven't already done so. */

+  if (*pdtbl == NULL)

+    *pdtbl = (d_derived_tbl *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(d_derived_tbl));

+  dtbl = *pdtbl;

+  dtbl->pub = htbl;		/* fill in back link */

+  

+  /* Figure C.1: make table of Huffman code length for each symbol */

+  /* Note that this is in code-length order. */

+

+  p = 0;

+  for (l = 1; l <= 16; l++) {

+    for (i = 1; i <= (int) htbl->bits[l]; i++)

+      huffsize[p++] = (char) l;

+  }

+  huffsize[p] = 0;

+  

+  /* Figure C.2: generate the codes themselves */

+  /* Note that this is in code-length order. */

+  

+  code = 0;

+  si = huffsize[0];

+  p = 0;

+  while (huffsize[p]) {

+    while (((int) huffsize[p]) == si) {

+      huffcode[p++] = code;

+      code++;

+    }

+    code <<= 1;

+    si++;

+  }

+

+  /* Figure F.15: generate decoding tables for bit-sequential decoding */

+

+  p = 0;

+  for (l = 1; l <= 16; l++) {

+    if (htbl->bits[l]) {

+      dtbl->valptr[l] = p; /* huffval[] index of 1st symbol of code length l */

+      dtbl->mincode[l] = huffcode[p]; /* minimum code of length l */

+      p += htbl->bits[l];

+      dtbl->maxcode[l] = huffcode[p-1]; /* maximum code of length l */

+    } else {

+      dtbl->maxcode[l] = -1;	/* -1 if no codes of this length */

+    }

+  }

+  dtbl->maxcode[17] = 0xFFFFFL; /* ensures jpeg_huff_decode terminates */

+

+  /* Compute lookahead tables to speed up decoding.

+   * First we set all the table entries to 0, indicating "too long";

+   * then we iterate through the Huffman codes that are short enough and

+   * fill in all the entries that correspond to bit sequences starting

+   * with that code.

+   */

+

+  MEMZERO(dtbl->look_nbits, SIZEOF(dtbl->look_nbits));

+

+  p = 0;

+  for (l = 1; l <= HUFF_LOOKAHEAD; l++) {

+    for (i = 1; i <= (int) htbl->bits[l]; i++, p++) {

+      /* l = current code's length, p = its index in huffcode[] & huffval[]. */

+      /* Generate left-justified code followed by all possible bit sequences */

+      lookbits = huffcode[p] << (HUFF_LOOKAHEAD-l);

+      for (ctr = 1 << (HUFF_LOOKAHEAD-l); ctr > 0; ctr--) {

+	dtbl->look_nbits[lookbits] = l;

+	dtbl->look_sym[lookbits] = htbl->huffval[p];

+	lookbits++;

+      }

+    }

+  }

+}

+

+

+/*

+ * Out-of-line code for bit fetching (shared with jdphuff.c).

+ * See jdhuff.h for info about usage.

+ * Note: current values of get_buffer and bits_left are passed as parameters,

+ * but are returned in the corresponding fields of the state struct.

+ *

+ * On most machines MIN_GET_BITS should be 25 to allow the full 32-bit width

+ * of get_buffer to be used.  (On machines with wider words, an even larger

+ * buffer could be used.)  However, on some machines 32-bit shifts are

+ * quite slow and take time proportional to the number of places shifted.

+ * (This is true with most PC compilers, for instance.)  In this case it may

+ * be a win to set MIN_GET_BITS to the minimum value of 15.  This reduces the

+ * average shift distance at the cost of more calls to jpeg_fill_bit_buffer.

+ */

+

+#ifdef SLOW_SHIFT_32

+#define MIN_GET_BITS  15	/* minimum allowable value */

+#else

+#define MIN_GET_BITS  (BIT_BUF_SIZE-7)

+#endif

+

+

+GLOBAL boolean

+jpeg_fill_bit_buffer (bitread_working_state * state,

+		      register bit_buf_type get_buffer, register int bits_left,

+		      int nbits)

+/* Load up the bit buffer to a depth of at least nbits */

+{

+  /* Copy heavily used state fields into locals (hopefully registers) */

+  register const JOCTET * next_input_byte = state->next_input_byte;

+  register size_t bytes_in_buffer = state->bytes_in_buffer;

+  register int c;

+

+  /* Attempt to load at least MIN_GET_BITS bits into get_buffer. */

+  /* (It is assumed that no request will be for more than that many bits.) */

+

+  while (bits_left < MIN_GET_BITS) {

+    /* Attempt to read a byte */

+    if (state->unread_marker != 0)

+      goto no_more_data;	/* can't advance past a marker */

+

+    if (bytes_in_buffer == 0) {

+      if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))

+	return FALSE;

+      next_input_byte = state->cinfo->src->next_input_byte;

+      bytes_in_buffer = state->cinfo->src->bytes_in_buffer;

+    }

+    bytes_in_buffer--;

+    c = GETJOCTET(*next_input_byte++);

+

+    /* If it's 0xFF, check and discard stuffed zero byte */

+    if (c == 0xFF) {

+      do {

+	if (bytes_in_buffer == 0) {

+	  if (! (*state->cinfo->src->fill_input_buffer) (state->cinfo))

+	    return FALSE;

+	  next_input_byte = state->cinfo->src->next_input_byte;

+	  bytes_in_buffer = state->cinfo->src->bytes_in_buffer;

+	}

+	bytes_in_buffer--;

+	c = GETJOCTET(*next_input_byte++);

+      } while (c == 0xFF);

+

+      if (c == 0) {

+	/* Found FF/00, which represents an FF data byte */

+	c = 0xFF;

+      } else {

+	/* Oops, it's actually a marker indicating end of compressed data. */

+	/* Better put it back for use later */

+	state->unread_marker = c;

+

+      no_more_data:

+	/* There should be enough bits still left in the data segment; */

+	/* if so, just break out of the outer while loop. */

+	if (bits_left >= nbits)

+	  break;

+	/* Uh-oh.  Report corrupted data to user and stuff zeroes into

+	 * the data stream, so that we can produce some kind of image.

+	 * Note that this code will be repeated for each byte demanded

+	 * for the rest of the segment.  We use a nonvolatile flag to ensure

+	 * that only one warning message appears.

+	 */

+	if (! *(state->printed_eod_ptr)) {

+	  WARNMS(state->cinfo, JWRN_HIT_MARKER);

+	  *(state->printed_eod_ptr) = TRUE;

+	}

+	c = 0;			/* insert a zero byte into bit buffer */

+      }

+    }

+

+    /* OK, load c into get_buffer */

+    get_buffer = (get_buffer << 8) | c;

+    bits_left += 8;

+  }

+

+  /* Unload the local registers */

+  state->next_input_byte = next_input_byte;

+  state->bytes_in_buffer = bytes_in_buffer;

+  state->get_buffer = get_buffer;

+  state->bits_left = bits_left;

+

+  return TRUE;

+}

+

+

+/*

+ * Out-of-line code for Huffman code decoding.

+ * See jdhuff.h for info about usage.

+ */

+

+GLOBAL int

+jpeg_huff_decode (bitread_working_state * state,

+		  register bit_buf_type get_buffer, register int bits_left,

+		  d_derived_tbl * htbl, int min_bits)

+{

+  register int l = min_bits;

+  register INT32 code;

+

+  /* HUFF_DECODE has determined that the code is at least min_bits */

+  /* bits long, so fetch that many bits in one swoop. */

+

+  CHECK_BIT_BUFFER(*state, l, return -1);

+  code = GET_BITS(l);

+

+  /* Collect the rest of the Huffman code one bit at a time. */

+  /* This is per Figure F.16 in the JPEG spec. */

+

+  while (code > htbl->maxcode[l]) {

+    code <<= 1;

+    CHECK_BIT_BUFFER(*state, 1, return -1);

+    code |= GET_BITS(1);

+    l++;

+  }

+

+  /* Unload the local registers */

+  state->get_buffer = get_buffer;

+  state->bits_left = bits_left;

+

+  /* With garbage input we may reach the sentinel value l = 17. */

+

+  if (l > 16) {

+    WARNMS(state->cinfo, JWRN_HUFF_BAD_CODE);

+    return 0;			/* fake a zero as the safest result */

+  }

+

+  return htbl->pub->huffval[ htbl->valptr[l] +

+			    ((int) (code - htbl->mincode[l])) ];

+}

+

+

+/*

+ * Figure F.12: extend sign bit.

+ * On some machines, a shift and add will be faster than a table lookup.

+ */

+

+#ifdef AVOID_TABLES

+

+#define HUFF_EXTEND(x,s)  ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))

+

+#else

+

+#define HUFF_EXTEND(x,s)  ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))

+

+static const int extend_test[16] =   /* entry n is 2**(n-1) */

+  { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,

+    0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };

+

+static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */

+  { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,

+    ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,

+    ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,

+    ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };

+

+#endif /* AVOID_TABLES */

+

+

+/*

+ * Check for a restart marker & resynchronize decoder.

+ * Returns FALSE if must suspend.

+ */

+

+LOCAL boolean

+process_restart (j_decompress_ptr cinfo)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  int ci;

+

+  /* Throw away any unused bits remaining in bit buffer; */

+  /* include any full bytes in next_marker's count of discarded bytes */

+  cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;

+  entropy->bitstate.bits_left = 0;

+

+  /* Advance past the RSTn marker */

+  if (! (*cinfo->marker->read_restart_marker) (cinfo))

+    return FALSE;

+

+  /* Re-initialize DC predictions to 0 */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++)

+    entropy->saved.last_dc_val[ci] = 0;

+

+  /* Reset restart counter */

+  entropy->restarts_to_go = cinfo->restart_interval;

+

+  /* Next segment can get another out-of-data warning */

+  entropy->bitstate.printed_eod = FALSE;

+

+  return TRUE;

+}

+

+

+/*

+ * Decode and return one MCU's worth of Huffman-compressed coefficients.

+ * The coefficients are reordered from zigzag order into natural array order,

+ * but are not dequantized.

+ *

+ * The i'th block of the MCU is stored into the block pointed to by

+ * MCU_data[i].  WE ASSUME THIS AREA HAS BEEN ZEROED BY THE CALLER.

+ * (Wholesale zeroing is usually a little faster than retail...)

+ *

+ * Returns FALSE if data source requested suspension.  In that case no

+ * changes have been made to permanent state.  (Exception: some output

+ * coefficients may already have been assigned.  This is harmless for

+ * this module, since we'll just re-assign them on the next call.)

+ */

+

+METHODDEF boolean

+decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)

+{

+  huff_entropy_ptr entropy = (huff_entropy_ptr) cinfo->entropy;

+  register int s, k, r;

+  int blkn, ci;

+  JBLOCKROW block;

+  BITREAD_STATE_VARS;

+  savable_state state;

+  d_derived_tbl * dctbl;

+  d_derived_tbl * actbl;

+  jpeg_component_info * compptr;

+

+  /* Process restart marker if needed; may have to suspend */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! process_restart(cinfo))

+	return FALSE;

+  }

+

+  /* Load up working state */

+  BITREAD_LOAD_STATE(cinfo,entropy->bitstate);

+  ASSIGN_STATE(state, entropy->saved);

+

+  /* Outer loop handles each block in the MCU */

+

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    block = MCU_data[blkn];

+    ci = cinfo->MCU_membership[blkn];

+    compptr = cinfo->cur_comp_info[ci];

+    dctbl = entropy->dc_derived_tbls[compptr->dc_tbl_no];

+    actbl = entropy->ac_derived_tbls[compptr->ac_tbl_no];

+

+    /* Decode a single block's worth of coefficients */

+

+    /* Section F.2.2.1: decode the DC coefficient difference */

+    HUFF_DECODE(s, br_state, dctbl, return FALSE, label1);

+    if (s) {

+      CHECK_BIT_BUFFER(br_state, s, return FALSE);

+      r = GET_BITS(s);

+      s = HUFF_EXTEND(r, s);

+    }

+

+    /* Shortcut if component's values are not interesting */

+    if (! compptr->component_needed)

+      goto skip_ACs;

+

+    /* Convert DC difference to actual value, update last_dc_val */

+    s += state.last_dc_val[ci];

+    state.last_dc_val[ci] = s;

+    /* Output the DC coefficient (assumes jpeg_natural_order[0] = 0) */

+    (*block)[0] = (JCOEF) s;

+

+    /* Do we need to decode the AC coefficients for this component? */

+    if (compptr->DCT_scaled_size > 1) {

+

+      /* Section F.2.2.2: decode the AC coefficients */

+      /* Since zeroes are skipped, output area must be cleared beforehand */

+      for (k = 1; k < DCTSIZE2; k++) {

+	HUFF_DECODE(s, br_state, actbl, return FALSE, label2);

+      

+	r = s >> 4;

+	s &= 15;

+      

+	if (s) {

+	  k += r;

+	  CHECK_BIT_BUFFER(br_state, s, return FALSE);

+	  r = GET_BITS(s);

+	  s = HUFF_EXTEND(r, s);

+	  /* Output coefficient in natural (dezigzagged) order.

+	   * Note: the extra entries in jpeg_natural_order[] will save us

+	   * if k >= DCTSIZE2, which could happen if the data is corrupted.

+	   */

+	  (*block)[jpeg_natural_order[k]] = (JCOEF) s;

+	} else {

+	  if (r != 15)

+	    break;

+	  k += 15;

+	}

+      }

+

+    } else {

+skip_ACs:

+

+      /* Section F.2.2.2: decode the AC coefficients */

+      /* In this path we just discard the values */

+      for (k = 1; k < DCTSIZE2; k++) {

+	HUFF_DECODE(s, br_state, actbl, return FALSE, label3);

+      

+	r = s >> 4;

+	s &= 15;

+      

+	if (s) {

+	  k += r;

+	  CHECK_BIT_BUFFER(br_state, s, return FALSE);

+	  DROP_BITS(s);

+	} else {

+	  if (r != 15)

+	    break;

+	  k += 15;

+	}

+      }

+

+    }

+  }

+

+  /* Completed MCU, so update state */

+  BITREAD_SAVE_STATE(cinfo,entropy->bitstate);

+  ASSIGN_STATE(entropy->saved, state);

+

+  /* Account for restart interval (no-op if not using restarts) */

+  entropy->restarts_to_go--;

+

+  return TRUE;

+}

+

+

+/*

+ * Module initialization routine for Huffman entropy decoding.

+ */

+

+GLOBAL void

+jinit_huff_decoder (j_decompress_ptr cinfo)

+{

+  huff_entropy_ptr entropy;

+  int i;

+

+  entropy = (huff_entropy_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(huff_entropy_decoder));

+  cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;

+  entropy->pub.start_pass = start_pass_huff_decoder;

+  entropy->pub.decode_mcu = decode_mcu;

+

+  /* Mark tables unallocated */

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    entropy->dc_derived_tbls[i] = entropy->ac_derived_tbls[i] = NULL;

+  }

+}

diff --git a/code/jpeg-6/jdhuff.h b/code/jpeg-6/jdhuff.h
new file mode 100755
index 0000000..65f3054
--- /dev/null
+++ b/code/jpeg-6/jdhuff.h
@@ -0,0 +1,202 @@
+/*

+ * jdhuff.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains declarations for Huffman entropy decoding routines

+ * that are shared between the sequential decoder (jdhuff.c) and the

+ * progressive decoder (jdphuff.c).  No other modules need to see these.

+ */

+

+/* Short forms of external names for systems with brain-damaged linkers. */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_make_d_derived_tbl	jMkDDerived

+#define jpeg_fill_bit_buffer	jFilBitBuf

+#define jpeg_huff_decode	jHufDecode

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+

+/* Derived data constructed for each Huffman table */

+

+#define HUFF_LOOKAHEAD	8	/* # of bits of lookahead */

+

+typedef struct {

+  /* Basic tables: (element [0] of each array is unused) */

+  INT32 mincode[17];		/* smallest code of length k */

+  INT32 maxcode[18];		/* largest code of length k (-1 if none) */

+  /* (maxcode[17] is a sentinel to ensure jpeg_huff_decode terminates) */

+  int valptr[17];		/* huffval[] index of 1st symbol of length k */

+

+  /* Link to public Huffman table (needed only in jpeg_huff_decode) */

+  JHUFF_TBL *pub;

+

+  /* Lookahead tables: indexed by the next HUFF_LOOKAHEAD bits of

+   * the input data stream.  If the next Huffman code is no more

+   * than HUFF_LOOKAHEAD bits long, we can obtain its length and

+   * the corresponding symbol directly from these tables.

+   */

+  int look_nbits[1<<HUFF_LOOKAHEAD]; /* # bits, or 0 if too long */

+  UINT8 look_sym[1<<HUFF_LOOKAHEAD]; /* symbol, or unused */

+} d_derived_tbl;

+

+/* Expand a Huffman table definition into the derived format */

+EXTERN void jpeg_make_d_derived_tbl JPP((j_decompress_ptr cinfo,

+				JHUFF_TBL * htbl, d_derived_tbl ** pdtbl));

+

+

+/*

+ * Fetching the next N bits from the input stream is a time-critical operation

+ * for the Huffman decoders.  We implement it with a combination of inline

+ * macros and out-of-line subroutines.  Note that N (the number of bits

+ * demanded at one time) never exceeds 15 for JPEG use.

+ *

+ * We read source bytes into get_buffer and dole out bits as needed.

+ * If get_buffer already contains enough bits, they are fetched in-line

+ * by the macros CHECK_BIT_BUFFER and GET_BITS.  When there aren't enough

+ * bits, jpeg_fill_bit_buffer is called; it will attempt to fill get_buffer

+ * as full as possible (not just to the number of bits needed; this

+ * prefetching reduces the overhead cost of calling jpeg_fill_bit_buffer).

+ * Note that jpeg_fill_bit_buffer may return FALSE to indicate suspension.

+ * On TRUE return, jpeg_fill_bit_buffer guarantees that get_buffer contains

+ * at least the requested number of bits --- dummy zeroes are inserted if

+ * necessary.

+ */

+

+typedef INT32 bit_buf_type;	/* type of bit-extraction buffer */

+#define BIT_BUF_SIZE  32	/* size of buffer in bits */

+

+/* If long is > 32 bits on your machine, and shifting/masking longs is

+ * reasonably fast, making bit_buf_type be long and setting BIT_BUF_SIZE

+ * appropriately should be a win.  Unfortunately we can't do this with

+ * something like  #define BIT_BUF_SIZE (sizeof(bit_buf_type)*8)

+ * because not all machines measure sizeof in 8-bit bytes.

+ */

+

+typedef struct {		/* Bitreading state saved across MCUs */

+  bit_buf_type get_buffer;	/* current bit-extraction buffer */

+  int bits_left;		/* # of unused bits in it */

+  boolean printed_eod;		/* flag to suppress multiple warning msgs */

+} bitread_perm_state;

+

+typedef struct {		/* Bitreading working state within an MCU */

+  /* current data source state */

+  const JOCTET * next_input_byte; /* => next byte to read from source */

+  size_t bytes_in_buffer;	/* # of bytes remaining in source buffer */

+  int unread_marker;		/* nonzero if we have hit a marker */

+  /* bit input buffer --- note these values are kept in register variables,

+   * not in this struct, inside the inner loops.

+   */

+  bit_buf_type get_buffer;	/* current bit-extraction buffer */

+  int bits_left;		/* # of unused bits in it */

+  /* pointers needed by jpeg_fill_bit_buffer */

+  j_decompress_ptr cinfo;	/* back link to decompress master record */

+  boolean * printed_eod_ptr;	/* => flag in permanent state */

+} bitread_working_state;

+

+/* Macros to declare and load/save bitread local variables. */

+#define BITREAD_STATE_VARS  \

+	register bit_buf_type get_buffer;  \

+	register int bits_left;  \

+	bitread_working_state br_state

+

+#define BITREAD_LOAD_STATE(cinfop,permstate)  \

+	br_state.cinfo = cinfop; \

+	br_state.next_input_byte = cinfop->src->next_input_byte; \

+	br_state.bytes_in_buffer = cinfop->src->bytes_in_buffer; \

+	br_state.unread_marker = cinfop->unread_marker; \

+	get_buffer = permstate.get_buffer; \

+	bits_left = permstate.bits_left; \

+	br_state.printed_eod_ptr = & permstate.printed_eod

+

+#define BITREAD_SAVE_STATE(cinfop,permstate)  \

+	cinfop->src->next_input_byte = br_state.next_input_byte; \

+	cinfop->src->bytes_in_buffer = br_state.bytes_in_buffer; \

+	cinfop->unread_marker = br_state.unread_marker; \

+	permstate.get_buffer = get_buffer; \

+	permstate.bits_left = bits_left

+

+/*

+ * These macros provide the in-line portion of bit fetching.

+ * Use CHECK_BIT_BUFFER to ensure there are N bits in get_buffer

+ * before using GET_BITS, PEEK_BITS, or DROP_BITS.

+ * The variables get_buffer and bits_left are assumed to be locals,

+ * but the state struct might not be (jpeg_huff_decode needs this).

+ *	CHECK_BIT_BUFFER(state,n,action);

+ *		Ensure there are N bits in get_buffer; if suspend, take action.

+ *      val = GET_BITS(n);

+ *		Fetch next N bits.

+ *      val = PEEK_BITS(n);

+ *		Fetch next N bits without removing them from the buffer.

+ *	DROP_BITS(n);

+ *		Discard next N bits.

+ * The value N should be a simple variable, not an expression, because it

+ * is evaluated multiple times.

+ */

+

+#define CHECK_BIT_BUFFER(state,nbits,action) \

+	{ if (bits_left < (nbits)) {  \

+	    if (! jpeg_fill_bit_buffer(&(state),get_buffer,bits_left,nbits))  \

+	      { action; }  \

+	    get_buffer = (state).get_buffer; bits_left = (state).bits_left; } }

+

+#define GET_BITS(nbits) \

+	(((int) (get_buffer >> (bits_left -= (nbits)))) & ((1<<(nbits))-1))

+

+#define PEEK_BITS(nbits) \

+	(((int) (get_buffer >> (bits_left -  (nbits)))) & ((1<<(nbits))-1))

+

+#define DROP_BITS(nbits) \

+	(bits_left -= (nbits))

+

+/* Load up the bit buffer to a depth of at least nbits */

+EXTERN boolean jpeg_fill_bit_buffer JPP((bitread_working_state * state,

+		register bit_buf_type get_buffer, register int bits_left,

+		int nbits));

+

+

+/*

+ * Code for extracting next Huffman-coded symbol from input bit stream.

+ * Again, this is time-critical and we make the main paths be macros.

+ *

+ * We use a lookahead table to process codes of up to HUFF_LOOKAHEAD bits

+ * without looping.  Usually, more than 95% of the Huffman codes will be 8

+ * or fewer bits long.  The few overlength codes are handled with a loop,

+ * which need not be inline code.

+ *

+ * Notes about the HUFF_DECODE macro:

+ * 1. Near the end of the data segment, we may fail to get enough bits

+ *    for a lookahead.  In that case, we do it the hard way.

+ * 2. If the lookahead table contains no entry, the next code must be

+ *    more than HUFF_LOOKAHEAD bits long.

+ * 3. jpeg_huff_decode returns -1 if forced to suspend.

+ */

+

+#define HUFF_DECODE(result,state,htbl,failaction,slowlabel) \

+{ register int nb, look; \

+  if (bits_left < HUFF_LOOKAHEAD) { \

+    if (! jpeg_fill_bit_buffer(&state,get_buffer,bits_left, 0)) {failaction;} \

+    get_buffer = state.get_buffer; bits_left = state.bits_left; \

+    if (bits_left < HUFF_LOOKAHEAD) { \

+      nb = 1; goto slowlabel; \

+    } \

+  } \

+  look = PEEK_BITS(HUFF_LOOKAHEAD); \

+  if ((nb = htbl->look_nbits[look]) != 0) { \

+    DROP_BITS(nb); \

+    result = htbl->look_sym[look]; \

+  } else { \

+    nb = HUFF_LOOKAHEAD+1; \

+slowlabel: \

+    if ((result=jpeg_huff_decode(&state,get_buffer,bits_left,htbl,nb)) < 0) \

+	{ failaction; } \

+    get_buffer = state.get_buffer; bits_left = state.bits_left; \

+  } \

+}

+

+/* Out-of-line case for Huffman code fetching */

+EXTERN int jpeg_huff_decode JPP((bitread_working_state * state,

+		register bit_buf_type get_buffer, register int bits_left,

+		d_derived_tbl * htbl, int min_bits));

diff --git a/code/jpeg-6/jdinput.c b/code/jpeg-6/jdinput.c
new file mode 100755
index 0000000..5b4774f
--- /dev/null
+++ b/code/jpeg-6/jdinput.c
@@ -0,0 +1,381 @@
+/*

+ * jdinput.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains input control logic for the JPEG decompressor.

+ * These routines are concerned with controlling the decompressor's input

+ * processing (marker reading and coefficient decoding).  The actual input

+ * reading is done in jdmarker.c, jdhuff.c, and jdphuff.c.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private state */

+

+typedef struct {

+  struct jpeg_input_controller pub; /* public fields */

+

+  boolean inheaders;		/* TRUE until first SOS is reached */

+} my_input_controller;

+

+typedef my_input_controller * my_inputctl_ptr;

+

+

+/* Forward declarations */

+METHODDEF int consume_markers JPP((j_decompress_ptr cinfo));

+

+

+/*

+ * Routines to calculate various quantities related to the size of the image.

+ */

+

+LOCAL void

+initial_setup (j_decompress_ptr cinfo)

+/* Called once, when first SOS marker is reached */

+{

+  int ci;

+  jpeg_component_info *compptr;

+

+  /* Make sure image isn't bigger than I can handle */

+  if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||

+      (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)

+    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);

+

+  /* For now, precision must match compiled-in value... */

+  if (cinfo->data_precision != BITS_IN_JSAMPLE)

+    ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);

+

+  /* Check that number of components won't exceed internal array sizes */

+  if (cinfo->num_components > MAX_COMPONENTS)

+    ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,

+	     MAX_COMPONENTS);

+

+  /* Compute maximum sampling factors; check factor validity */

+  cinfo->max_h_samp_factor = 1;

+  cinfo->max_v_samp_factor = 1;

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||

+	compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)

+      ERREXIT(cinfo, JERR_BAD_SAMPLING);

+    cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,

+				   compptr->h_samp_factor);

+    cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,

+				   compptr->v_samp_factor);

+  }

+

+  /* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.

+   * In the full decompressor, this will be overridden by jdmaster.c;

+   * but in the transcoder, jdmaster.c is not used, so we must do it here.

+   */

+  cinfo->min_DCT_scaled_size = DCTSIZE;

+

+  /* Compute dimensions of components */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    compptr->DCT_scaled_size = DCTSIZE;

+    /* Size in DCT blocks */

+    compptr->width_in_blocks = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,

+		    (long) (cinfo->max_h_samp_factor * DCTSIZE));

+    compptr->height_in_blocks = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,

+		    (long) (cinfo->max_v_samp_factor * DCTSIZE));

+    /* downsampled_width and downsampled_height will also be overridden by

+     * jdmaster.c if we are doing full decompression.  The transcoder library

+     * doesn't use these values, but the calling application might.

+     */

+    /* Size in samples */

+    compptr->downsampled_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,

+		    (long) cinfo->max_h_samp_factor);

+    compptr->downsampled_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,

+		    (long) cinfo->max_v_samp_factor);

+    /* Mark component needed, until color conversion says otherwise */

+    compptr->component_needed = TRUE;

+    /* Mark no quantization table yet saved for component */

+    compptr->quant_table = NULL;

+  }

+

+  /* Compute number of fully interleaved MCU rows. */

+  cinfo->total_iMCU_rows = (JDIMENSION)

+    jdiv_round_up((long) cinfo->image_height,

+		  (long) (cinfo->max_v_samp_factor*DCTSIZE));

+

+  /* Decide whether file contains multiple scans */

+  if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)

+    cinfo->inputctl->has_multiple_scans = TRUE;

+  else

+    cinfo->inputctl->has_multiple_scans = FALSE;

+}

+

+

+LOCAL void

+per_scan_setup (j_decompress_ptr cinfo)

+/* Do computations that are needed before processing a JPEG scan */

+/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */

+{

+  int ci, mcublks, tmp;

+  jpeg_component_info *compptr;

+  

+  if (cinfo->comps_in_scan == 1) {

+    

+    /* Noninterleaved (single-component) scan */

+    compptr = cinfo->cur_comp_info[0];

+    

+    /* Overall image size in MCUs */

+    cinfo->MCUs_per_row = compptr->width_in_blocks;

+    cinfo->MCU_rows_in_scan = compptr->height_in_blocks;

+    

+    /* For noninterleaved scan, always one block per MCU */

+    compptr->MCU_width = 1;

+    compptr->MCU_height = 1;

+    compptr->MCU_blocks = 1;

+    compptr->MCU_sample_width = compptr->DCT_scaled_size;

+    compptr->last_col_width = 1;

+    /* For noninterleaved scans, it is convenient to define last_row_height

+     * as the number of block rows present in the last iMCU row.

+     */

+    tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);

+    if (tmp == 0) tmp = compptr->v_samp_factor;

+    compptr->last_row_height = tmp;

+    

+    /* Prepare array describing MCU composition */

+    cinfo->blocks_in_MCU = 1;

+    cinfo->MCU_membership[0] = 0;

+    

+  } else {

+    

+    /* Interleaved (multi-component) scan */

+    if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)

+      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,

+	       MAX_COMPS_IN_SCAN);

+    

+    /* Overall image size in MCUs */

+    cinfo->MCUs_per_row = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width,

+		    (long) (cinfo->max_h_samp_factor*DCTSIZE));

+    cinfo->MCU_rows_in_scan = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height,

+		    (long) (cinfo->max_v_samp_factor*DCTSIZE));

+    

+    cinfo->blocks_in_MCU = 0;

+    

+    for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+      compptr = cinfo->cur_comp_info[ci];

+      /* Sampling factors give # of blocks of component in each MCU */

+      compptr->MCU_width = compptr->h_samp_factor;

+      compptr->MCU_height = compptr->v_samp_factor;

+      compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;

+      compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_scaled_size;

+      /* Figure number of non-dummy blocks in last MCU column & row */

+      tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);

+      if (tmp == 0) tmp = compptr->MCU_width;

+      compptr->last_col_width = tmp;

+      tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);

+      if (tmp == 0) tmp = compptr->MCU_height;

+      compptr->last_row_height = tmp;

+      /* Prepare array describing MCU composition */

+      mcublks = compptr->MCU_blocks;

+      if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU)

+	ERREXIT(cinfo, JERR_BAD_MCU_SIZE);

+      while (mcublks-- > 0) {

+	cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;

+      }

+    }

+    

+  }

+}

+

+

+/*

+ * Save away a copy of the Q-table referenced by each component present

+ * in the current scan, unless already saved during a prior scan.

+ *

+ * In a multiple-scan JPEG file, the encoder could assign different components

+ * the same Q-table slot number, but change table definitions between scans

+ * so that each component uses a different Q-table.  (The IJG encoder is not

+ * currently capable of doing this, but other encoders might.)  Since we want

+ * to be able to dequantize all the components at the end of the file, this

+ * means that we have to save away the table actually used for each component.

+ * We do this by copying the table at the start of the first scan containing

+ * the component.

+ * The JPEG spec prohibits the encoder from changing the contents of a Q-table

+ * slot between scans of a component using that slot.  If the encoder does so

+ * anyway, this decoder will simply use the Q-table values that were current

+ * at the start of the first scan for the component.

+ *

+ * The decompressor output side looks only at the saved quant tables,

+ * not at the current Q-table slots.

+ */

+

+LOCAL void

+latch_quant_tables (j_decompress_ptr cinfo)

+{

+  int ci, qtblno;

+  jpeg_component_info *compptr;

+  JQUANT_TBL * qtbl;

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    /* No work if we already saved Q-table for this component */

+    if (compptr->quant_table != NULL)

+      continue;

+    /* Make sure specified quantization table is present */

+    qtblno = compptr->quant_tbl_no;

+    if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||

+	cinfo->quant_tbl_ptrs[qtblno] == NULL)

+      ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);

+    /* OK, save away the quantization table */

+    qtbl = (JQUANT_TBL *)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(JQUANT_TBL));

+    MEMCOPY(qtbl, cinfo->quant_tbl_ptrs[qtblno], SIZEOF(JQUANT_TBL));

+    compptr->quant_table = qtbl;

+  }

+}

+

+

+/*

+ * Initialize the input modules to read a scan of compressed data.

+ * The first call to this is done by jdmaster.c after initializing

+ * the entire decompressor (during jpeg_start_decompress).

+ * Subsequent calls come from consume_markers, below.

+ */

+

+METHODDEF void

+start_input_pass (j_decompress_ptr cinfo)

+{

+  per_scan_setup(cinfo);

+  latch_quant_tables(cinfo);

+  (*cinfo->entropy->start_pass) (cinfo);

+  (*cinfo->coef->start_input_pass) (cinfo);

+  cinfo->inputctl->consume_input = cinfo->coef->consume_data;

+}

+

+

+/*

+ * Finish up after inputting a compressed-data scan.

+ * This is called by the coefficient controller after it's read all

+ * the expected data of the scan.

+ */

+

+METHODDEF void

+finish_input_pass (j_decompress_ptr cinfo)

+{

+  cinfo->inputctl->consume_input = consume_markers;

+}

+

+

+/*

+ * Read JPEG markers before, between, or after compressed-data scans.

+ * Change state as necessary when a new scan is reached.

+ * Return value is JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.

+ *

+ * The consume_input method pointer points either here or to the

+ * coefficient controller's consume_data routine, depending on whether

+ * we are reading a compressed data segment or inter-segment markers.

+ */

+

+METHODDEF int

+consume_markers (j_decompress_ptr cinfo)

+{

+  my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;

+  int val;

+

+  if (inputctl->pub.eoi_reached) /* After hitting EOI, read no further */

+    return JPEG_REACHED_EOI;

+

+  val = (*cinfo->marker->read_markers) (cinfo);

+

+  switch (val) {

+  case JPEG_REACHED_SOS:	/* Found SOS */

+    if (inputctl->inheaders) {	/* 1st SOS */

+      initial_setup(cinfo);

+      inputctl->inheaders = FALSE;

+      /* Note: start_input_pass must be called by jdmaster.c

+       * before any more input can be consumed.  jdapi.c is

+       * responsible for enforcing this sequencing.

+       */

+    } else {			/* 2nd or later SOS marker */

+      if (! inputctl->pub.has_multiple_scans)

+	ERREXIT(cinfo, JERR_EOI_EXPECTED); /* Oops, I wasn't expecting this! */

+      start_input_pass(cinfo);

+    }

+    break;

+  case JPEG_REACHED_EOI:	/* Found EOI */

+    inputctl->pub.eoi_reached = TRUE;

+    if (inputctl->inheaders) {	/* Tables-only datastream, apparently */

+      if (cinfo->marker->saw_SOF)

+	ERREXIT(cinfo, JERR_SOF_NO_SOS);

+    } else {

+      /* Prevent infinite loop in coef ctlr's decompress_data routine

+       * if user set output_scan_number larger than number of scans.

+       */

+      if (cinfo->output_scan_number > cinfo->input_scan_number)

+	cinfo->output_scan_number = cinfo->input_scan_number;

+    }

+    break;

+  case JPEG_SUSPENDED:

+    break;

+  }

+

+  return val;

+}

+

+

+/*

+ * Reset state to begin a fresh datastream.

+ */

+

+METHODDEF void

+reset_input_controller (j_decompress_ptr cinfo)

+{

+  my_inputctl_ptr inputctl = (my_inputctl_ptr) cinfo->inputctl;

+

+  inputctl->pub.consume_input = consume_markers;

+  inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */

+  inputctl->pub.eoi_reached = FALSE;

+  inputctl->inheaders = TRUE;

+  /* Reset other modules */

+  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);

+  (*cinfo->marker->reset_marker_reader) (cinfo);

+  /* Reset progression state -- would be cleaner if entropy decoder did this */

+  cinfo->coef_bits = NULL;

+}

+

+

+/*

+ * Initialize the input controller module.

+ * This is called only once, when the decompression object is created.

+ */

+

+GLOBAL void

+jinit_input_controller (j_decompress_ptr cinfo)

+{

+  my_inputctl_ptr inputctl;

+

+  /* Create subobject in permanent pool */

+  inputctl = (my_inputctl_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				SIZEOF(my_input_controller));

+  cinfo->inputctl = (struct jpeg_input_controller *) inputctl;

+  /* Initialize method pointers */

+  inputctl->pub.consume_input = consume_markers;

+  inputctl->pub.reset_input_controller = reset_input_controller;

+  inputctl->pub.start_input_pass = start_input_pass;

+  inputctl->pub.finish_input_pass = finish_input_pass;

+  /* Initialize state: can't use reset_input_controller since we don't

+   * want to try to reset other modules yet.

+   */

+  inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */

+  inputctl->pub.eoi_reached = FALSE;

+  inputctl->inheaders = TRUE;

+}

diff --git a/code/jpeg-6/jdmainct.c b/code/jpeg-6/jdmainct.c
new file mode 100755
index 0000000..7059cdf
--- /dev/null
+++ b/code/jpeg-6/jdmainct.c
@@ -0,0 +1,520 @@
+/*

+ * jdmainct.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the main buffer controller for decompression.

+ * The main buffer lies between the JPEG decompressor proper and the

+ * post-processor; it holds downsampled data in the JPEG colorspace.

+ *

+ * Note that this code is bypassed in raw-data mode, since the application

+ * supplies the equivalent of the main buffer in that case.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * In the current system design, the main buffer need never be a full-image

+ * buffer; any full-height buffers will be found inside the coefficient or

+ * postprocessing controllers.  Nonetheless, the main controller is not

+ * trivial.  Its responsibility is to provide context rows for upsampling/

+ * rescaling, and doing this in an efficient fashion is a bit tricky.

+ *

+ * Postprocessor input data is counted in "row groups".  A row group

+ * is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size)

+ * sample rows of each component.  (We require DCT_scaled_size values to be

+ * chosen such that these numbers are integers.  In practice DCT_scaled_size

+ * values will likely be powers of two, so we actually have the stronger

+ * condition that DCT_scaled_size / min_DCT_scaled_size is an integer.)

+ * Upsampling will typically produce max_v_samp_factor pixel rows from each

+ * row group (times any additional scale factor that the upsampler is

+ * applying).

+ *

+ * The coefficient controller will deliver data to us one iMCU row at a time;

+ * each iMCU row contains v_samp_factor * DCT_scaled_size sample rows, or

+ * exactly min_DCT_scaled_size row groups.  (This amount of data corresponds

+ * to one row of MCUs when the image is fully interleaved.)  Note that the

+ * number of sample rows varies across components, but the number of row

+ * groups does not.  Some garbage sample rows may be included in the last iMCU

+ * row at the bottom of the image.

+ *

+ * Depending on the vertical scaling algorithm used, the upsampler may need

+ * access to the sample row(s) above and below its current input row group.

+ * The upsampler is required to set need_context_rows TRUE at global selection

+ * time if so.  When need_context_rows is FALSE, this controller can simply

+ * obtain one iMCU row at a time from the coefficient controller and dole it

+ * out as row groups to the postprocessor.

+ *

+ * When need_context_rows is TRUE, this controller guarantees that the buffer

+ * passed to postprocessing contains at least one row group's worth of samples

+ * above and below the row group(s) being processed.  Note that the context

+ * rows "above" the first passed row group appear at negative row offsets in

+ * the passed buffer.  At the top and bottom of the image, the required

+ * context rows are manufactured by duplicating the first or last real sample

+ * row; this avoids having special cases in the upsampling inner loops.

+ *

+ * The amount of context is fixed at one row group just because that's a

+ * convenient number for this controller to work with.  The existing

+ * upsamplers really only need one sample row of context.  An upsampler

+ * supporting arbitrary output rescaling might wish for more than one row

+ * group of context when shrinking the image; tough, we don't handle that.

+ * (This is justified by the assumption that downsizing will be handled mostly

+ * by adjusting the DCT_scaled_size values, so that the actual scale factor at

+ * the upsample step needn't be much less than one.)

+ *

+ * To provide the desired context, we have to retain the last two row groups

+ * of one iMCU row while reading in the next iMCU row.  (The last row group

+ * can't be processed until we have another row group for its below-context,

+ * and so we have to save the next-to-last group too for its above-context.)

+ * We could do this most simply by copying data around in our buffer, but

+ * that'd be very slow.  We can avoid copying any data by creating a rather

+ * strange pointer structure.  Here's how it works.  We allocate a workspace

+ * consisting of M+2 row groups (where M = min_DCT_scaled_size is the number

+ * of row groups per iMCU row).  We create two sets of redundant pointers to

+ * the workspace.  Labeling the physical row groups 0 to M+1, the synthesized

+ * pointer lists look like this:

+ *                   M+1                          M-1

+ * master pointer --> 0         master pointer --> 0

+ *                    1                            1

+ *                   ...                          ...

+ *                   M-3                          M-3

+ *                   M-2                           M

+ *                   M-1                          M+1

+ *                    M                           M-2

+ *                   M+1                          M-1

+ *                    0                            0

+ * We read alternate iMCU rows using each master pointer; thus the last two

+ * row groups of the previous iMCU row remain un-overwritten in the workspace.

+ * The pointer lists are set up so that the required context rows appear to

+ * be adjacent to the proper places when we pass the pointer lists to the

+ * upsampler.

+ *

+ * The above pictures describe the normal state of the pointer lists.

+ * At top and bottom of the image, we diddle the pointer lists to duplicate

+ * the first or last sample row as necessary (this is cheaper than copying

+ * sample rows around).

+ *

+ * This scheme breaks down if M < 2, ie, min_DCT_scaled_size is 1.  In that

+ * situation each iMCU row provides only one row group so the buffering logic

+ * must be different (eg, we must read two iMCU rows before we can emit the

+ * first row group).  For now, we simply do not support providing context

+ * rows when min_DCT_scaled_size is 1.  That combination seems unlikely to

+ * be worth providing --- if someone wants a 1/8th-size preview, they probably

+ * want it quick and dirty, so a context-free upsampler is sufficient.

+ */

+

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_d_main_controller pub; /* public fields */

+

+  /* Pointer to allocated workspace (M or M+2 row groups). */

+  JSAMPARRAY buffer[MAX_COMPONENTS];

+

+  boolean buffer_full;		/* Have we gotten an iMCU row from decoder? */

+  JDIMENSION rowgroup_ctr;	/* counts row groups output to postprocessor */

+

+  /* Remaining fields are only used in the context case. */

+

+  /* These are the master pointers to the funny-order pointer lists. */

+  JSAMPIMAGE xbuffer[2];	/* pointers to weird pointer lists */

+

+  int whichptr;			/* indicates which pointer set is now in use */

+  int context_state;		/* process_data state machine status */

+  JDIMENSION rowgroups_avail;	/* row groups available to postprocessor */

+  JDIMENSION iMCU_row_ctr;	/* counts iMCU rows to detect image top/bot */

+} my_main_controller;

+

+typedef my_main_controller * my_main_ptr;

+

+/* context_state values: */

+#define CTX_PREPARE_FOR_IMCU	0	/* need to prepare for MCU row */

+#define CTX_PROCESS_IMCU	1	/* feeding iMCU to postprocessor */

+#define CTX_POSTPONED_ROW	2	/* feeding postponed row group */

+

+

+/* Forward declarations */

+METHODDEF void process_data_simple_main

+	JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,

+	     JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));

+METHODDEF void process_data_context_main

+	JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,

+	     JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));

+#ifdef QUANT_2PASS_SUPPORTED

+METHODDEF void process_data_crank_post

+	JPP((j_decompress_ptr cinfo, JSAMPARRAY output_buf,

+	     JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));

+#endif

+

+

+LOCAL void

+alloc_funny_pointers (j_decompress_ptr cinfo)

+/* Allocate space for the funny pointer lists.

+ * This is done only once, not once per pass.

+ */

+{

+  // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+  int ci, rgroup;

+  int M = cinfo->min_DCT_scaled_size;

+  jpeg_component_info *compptr;

+  JSAMPARRAY xbuf;

+

+  /* Get top-level space for component array pointers.

+   * We alloc both arrays with one call to save a few cycles.

+   */

+  jmain->xbuffer[0] = (JSAMPIMAGE)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				cinfo->num_components * 2 * SIZEOF(JSAMPARRAY));

+  jmain->xbuffer[1] = jmain->xbuffer[0] + cinfo->num_components;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /

+      cinfo->min_DCT_scaled_size; /* height of a row group of component */

+    /* Get space for pointer lists --- M+4 row groups in each list.

+     * We alloc both pointer lists with one call to save a few cycles.

+     */

+    xbuf = (JSAMPARRAY)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW));

+    xbuf += rgroup;		/* want one row group at negative offsets */

+    jmain->xbuffer[0][ci] = xbuf;

+    xbuf += rgroup * (M + 4);

+    jmain->xbuffer[1][ci] = xbuf;

+  }

+}

+

+

+LOCAL void

+make_funny_pointers (j_decompress_ptr cinfo)

+/* Create the funny pointer lists discussed in the comments above.

+ * The actual workspace is already allocated (in main->buffer),

+ * and the space for the pointer lists is allocated too.

+ * This routine just fills in the curiously ordered lists.

+ * This will be repeated at the beginning of each pass.

+ */

+{

+ // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+  int ci, i, rgroup;

+  int M = cinfo->min_DCT_scaled_size;

+  jpeg_component_info *compptr;

+  JSAMPARRAY buf, xbuf0, xbuf1;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /

+      cinfo->min_DCT_scaled_size; /* height of a row group of component */

+    xbuf0 = jmain->xbuffer[0][ci];

+    xbuf1 = jmain->xbuffer[1][ci];

+    /* First copy the workspace pointers as-is */

+    buf = jmain->buffer[ci];

+    for (i = 0; i < rgroup * (M + 2); i++) {

+      xbuf0[i] = xbuf1[i] = buf[i];

+    }

+    /* In the second list, put the last four row groups in swapped order */

+    for (i = 0; i < rgroup * 2; i++) {

+      xbuf1[rgroup*(M-2) + i] = buf[rgroup*M + i];

+      xbuf1[rgroup*M + i] = buf[rgroup*(M-2) + i];

+    }

+    /* The wraparound pointers at top and bottom will be filled later

+     * (see set_wraparound_pointers, below).  Initially we want the "above"

+     * pointers to duplicate the first actual data line.  This only needs

+     * to happen in xbuffer[0].

+     */

+    for (i = 0; i < rgroup; i++) {

+      xbuf0[i - rgroup] = xbuf0[0];

+    }

+  }

+}

+

+

+LOCAL void

+set_wraparound_pointers (j_decompress_ptr cinfo)

+/* Set up the "wraparound" pointers at top and bottom of the pointer lists.

+ * This changes the pointer list state from top-of-image to the normal state.

+ */

+{

+ // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+  int ci, i, rgroup;

+  int M = cinfo->min_DCT_scaled_size;

+  jpeg_component_info *compptr;

+  JSAMPARRAY xbuf0, xbuf1;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /

+      cinfo->min_DCT_scaled_size; /* height of a row group of component */

+    xbuf0 = jmain->xbuffer[0][ci];

+    xbuf1 = jmain->xbuffer[1][ci];

+    for (i = 0; i < rgroup; i++) {

+      xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i];

+      xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i];

+      xbuf0[rgroup*(M+2) + i] = xbuf0[i];

+      xbuf1[rgroup*(M+2) + i] = xbuf1[i];

+    }

+  }

+}

+

+

+LOCAL void

+set_bottom_pointers (j_decompress_ptr cinfo)

+/* Change the pointer lists to duplicate the last sample row at the bottom

+ * of the image.  whichptr indicates which xbuffer holds the final iMCU row.

+ * Also sets rowgroups_avail to indicate number of nondummy row groups in row.

+ */

+{

+ // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+  int ci, i, rgroup, iMCUheight, rows_left;

+  jpeg_component_info *compptr;

+  JSAMPARRAY xbuf;

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Count sample rows in one iMCU row and in one row group */

+    iMCUheight = compptr->v_samp_factor * compptr->DCT_scaled_size;

+    rgroup = iMCUheight / cinfo->min_DCT_scaled_size;

+    /* Count nondummy sample rows remaining for this component */

+    rows_left = (int) (compptr->downsampled_height % (JDIMENSION) iMCUheight);

+    if (rows_left == 0) rows_left = iMCUheight;

+    /* Count nondummy row groups.  Should get same answer for each component,

+     * so we need only do it once.

+     */

+    if (ci == 0) {

+      jmain->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);

+    }

+    /* Duplicate the last real sample row rgroup*2 times; this pads out the

+     * last partial rowgroup and ensures at least one full rowgroup of context.

+     */

+    xbuf = jmain->xbuffer[jmain->whichptr][ci];

+    for (i = 0; i < rgroup * 2; i++) {

+      xbuf[rows_left + i] = xbuf[rows_left-1];

+    }

+  }

+}

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+

+  switch (pass_mode) {

+  case JBUF_PASS_THRU:

+    if (cinfo->upsample->need_context_rows) {

+      jmain->pub.process_data = process_data_context_main;

+      make_funny_pointers(cinfo); /* Create the xbuffer[] lists */

+      jmain->whichptr = 0;	/* Read first iMCU row into xbuffer[0] */

+      jmain->context_state = CTX_PREPARE_FOR_IMCU;

+      jmain->iMCU_row_ctr = 0;

+    } else {

+      /* Simple case with no context needed */

+      jmain->pub.process_data = process_data_simple_main;

+    }

+    jmain->buffer_full = FALSE;	/* Mark buffer empty */

+    jmain->rowgroup_ctr = 0;

+    break;

+#ifdef QUANT_2PASS_SUPPORTED

+  case JBUF_CRANK_DEST:

+    /* For last pass of 2-pass quantization, just crank the postprocessor */

+    jmain->pub.process_data = process_data_crank_post;

+    break;

+#endif

+  default:

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    break;

+  }

+}

+

+

+/*

+ * Process some data.

+ * This handles the simple case where no context is required.

+ */

+

+METHODDEF void

+process_data_simple_main (j_decompress_ptr cinfo,

+			  JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+			  JDIMENSION out_rows_avail)

+{

+  // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+  JDIMENSION rowgroups_avail;

+

+  /* Read input data if we haven't filled the main buffer yet */

+  if (! jmain->buffer_full) {

+    if (! (*cinfo->coef->decompress_data) (cinfo, jmain->buffer))

+      return;			/* suspension forced, can do nothing more */

+    jmain->buffer_full = TRUE;	/* OK, we have an iMCU row to work with */

+  }

+

+  /* There are always min_DCT_scaled_size row groups in an iMCU row. */

+  rowgroups_avail = (JDIMENSION) cinfo->min_DCT_scaled_size;

+  /* Note: at the bottom of the image, we may pass extra garbage row groups

+   * to the postprocessor.  The postprocessor has to check for bottom

+   * of image anyway (at row resolution), so no point in us doing it too.

+   */

+

+  /* Feed the postprocessor */

+  (*cinfo->post->post_process_data) (cinfo, jmain->buffer,

+				     &jmain->rowgroup_ctr, rowgroups_avail,

+				     output_buf, out_row_ctr, out_rows_avail);

+

+  /* Has postprocessor consumed all the data yet? If so, mark buffer empty */

+  if (jmain->rowgroup_ctr >= rowgroups_avail) {

+    jmain->buffer_full = FALSE;

+    jmain->rowgroup_ctr = 0;

+  }

+}

+

+

+/*

+ * Process some data.

+ * This handles the case where context rows must be provided.

+ */

+

+METHODDEF void

+process_data_context_main (j_decompress_ptr cinfo,

+			   JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+			   JDIMENSION out_rows_avail)

+{

+  // bk001204 - no use main

+  my_main_ptr jmain = (my_main_ptr) cinfo->main;

+

+  /* Read input data if we haven't filled the main buffer yet */

+  if (! jmain->buffer_full) {

+    if (! (*cinfo->coef->decompress_data) (cinfo,

+					   jmain->xbuffer[jmain->whichptr]))

+      return;			/* suspension forced, can do nothing more */

+    jmain->buffer_full = TRUE;	/* OK, we have an iMCU row to work with */

+    jmain->iMCU_row_ctr++;	/* count rows received */

+  }

+

+  /* Postprocessor typically will not swallow all the input data it is handed

+   * in one call (due to filling the output buffer first).  Must be prepared

+   * to exit and restart.  This switch lets us keep track of how far we got.

+   * Note that each case falls through to the next on successful completion.

+   */

+  switch (jmain->context_state) {

+  case CTX_POSTPONED_ROW:

+    /* Call postprocessor using previously set pointers for postponed row */

+    (*cinfo->post->post_process_data) (cinfo, jmain->xbuffer[jmain->whichptr],

+			&jmain->rowgroup_ctr, jmain->rowgroups_avail,

+			output_buf, out_row_ctr, out_rows_avail);

+    if (jmain->rowgroup_ctr < jmain->rowgroups_avail)

+      return;			/* Need to suspend */

+    jmain->context_state = CTX_PREPARE_FOR_IMCU;

+    if (*out_row_ctr >= out_rows_avail)

+      return;			/* Postprocessor exactly filled output buf */

+    /*FALLTHROUGH*/

+  case CTX_PREPARE_FOR_IMCU:

+    /* Prepare to process first M-1 row groups of this iMCU row */

+    jmain->rowgroup_ctr = 0;

+    jmain->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_scaled_size - 1);

+    /* Check for bottom of image: if so, tweak pointers to "duplicate"

+     * the last sample row, and adjust rowgroups_avail to ignore padding rows.

+     */

+    if (jmain->iMCU_row_ctr == cinfo->total_iMCU_rows)

+      set_bottom_pointers(cinfo);

+    jmain->context_state = CTX_PROCESS_IMCU;

+    /*FALLTHROUGH*/

+  case CTX_PROCESS_IMCU:

+    /* Call postprocessor using previously set pointers */

+    (*cinfo->post->post_process_data) (cinfo, jmain->xbuffer[jmain->whichptr],

+			&jmain->rowgroup_ctr, jmain->rowgroups_avail,

+			output_buf, out_row_ctr, out_rows_avail);

+    if (jmain->rowgroup_ctr < jmain->rowgroups_avail)

+      return;			/* Need to suspend */

+    /* After the first iMCU, change wraparound pointers to normal state */

+    if (jmain->iMCU_row_ctr == 1)

+      set_wraparound_pointers(cinfo);

+    /* Prepare to load new iMCU row using other xbuffer list */

+    jmain->whichptr ^= 1;	/* 0=>1 or 1=>0 */

+    jmain->buffer_full = FALSE;

+    /* Still need to process last row group of this iMCU row, */

+    /* which is saved at index M+1 of the other xbuffer */

+    jmain->rowgroup_ctr = (JDIMENSION) (cinfo->min_DCT_scaled_size + 1);

+    jmain->rowgroups_avail = (JDIMENSION) (cinfo->min_DCT_scaled_size + 2);

+    jmain->context_state = CTX_POSTPONED_ROW;

+  }

+}

+

+

+/*

+ * Process some data.

+ * Final pass of two-pass quantization: just call the postprocessor.

+ * Source data will be the postprocessor controller's internal buffer.

+ */

+

+#ifdef QUANT_2PASS_SUPPORTED

+

+METHODDEF void

+process_data_crank_post (j_decompress_ptr cinfo,

+			 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+			 JDIMENSION out_rows_avail)

+{

+  (*cinfo->post->post_process_data) (cinfo, (JSAMPIMAGE) NULL,

+				     (JDIMENSION *) NULL, (JDIMENSION) 0,

+				     output_buf, out_row_ctr, out_rows_avail);

+}

+

+#endif /* QUANT_2PASS_SUPPORTED */

+

+

+/*

+ * Initialize main buffer controller.

+ */

+

+GLOBAL void

+jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer)

+{

+  // bk001204 - no use main

+  my_main_ptr jmain;

+  int ci, rgroup, ngroups;

+  jpeg_component_info *compptr;

+

+  jmain = (my_main_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_main_controller));

+  cinfo->main = (struct jpeg_d_main_controller *) jmain;

+  jmain->pub.start_pass = start_pass_main;

+

+  if (need_full_buffer)		/* shouldn't happen */

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+

+  /* Allocate the workspace.

+   * ngroups is the number of row groups we need.

+   */

+  if (cinfo->upsample->need_context_rows) {

+    if (cinfo->min_DCT_scaled_size < 2) /* unsupported, see comments above */

+      ERREXIT(cinfo, JERR_NOTIMPL);

+    alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */

+    ngroups = cinfo->min_DCT_scaled_size + 2;

+  } else {

+    ngroups = cinfo->min_DCT_scaled_size;

+  }

+

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    rgroup = (compptr->v_samp_factor * compptr->DCT_scaled_size) /

+      cinfo->min_DCT_scaled_size; /* height of a row group of component */

+    jmain->buffer[ci] = (*cinfo->mem->alloc_sarray)

+			((j_common_ptr) cinfo, JPOOL_IMAGE,

+			 compptr->width_in_blocks * compptr->DCT_scaled_size,

+			 (JDIMENSION) (rgroup * ngroups));

+  }

+}

diff --git a/code/jpeg-6/jdmarker.c b/code/jpeg-6/jdmarker.c
new file mode 100755
index 0000000..6c3c519
--- /dev/null
+++ b/code/jpeg-6/jdmarker.c
@@ -0,0 +1,1052 @@
+/*

+ * jdmarker.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains routines to decode JPEG datastream markers.

+ * Most of the complexity arises from our desire to support input

+ * suspension: if not all of the data for a marker is available,

+ * we must exit back to the application.  On resumption, we reprocess

+ * the marker.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+typedef enum {			/* JPEG marker codes */

+  M_SOF0  = 0xc0,

+  M_SOF1  = 0xc1,

+  M_SOF2  = 0xc2,

+  M_SOF3  = 0xc3,

+  

+  M_SOF5  = 0xc5,

+  M_SOF6  = 0xc6,

+  M_SOF7  = 0xc7,

+  

+  M_JPG   = 0xc8,

+  M_SOF9  = 0xc9,

+  M_SOF10 = 0xca,

+  M_SOF11 = 0xcb,

+  

+  M_SOF13 = 0xcd,

+  M_SOF14 = 0xce,

+  M_SOF15 = 0xcf,

+  

+  M_DHT   = 0xc4,

+  

+  M_DAC   = 0xcc,

+  

+  M_RST0  = 0xd0,

+  M_RST1  = 0xd1,

+  M_RST2  = 0xd2,

+  M_RST3  = 0xd3,

+  M_RST4  = 0xd4,

+  M_RST5  = 0xd5,

+  M_RST6  = 0xd6,

+  M_RST7  = 0xd7,

+  

+  M_SOI   = 0xd8,

+  M_EOI   = 0xd9,

+  M_SOS   = 0xda,

+  M_DQT   = 0xdb,

+  M_DNL   = 0xdc,

+  M_DRI   = 0xdd,

+  M_DHP   = 0xde,

+  M_EXP   = 0xdf,

+  

+  M_APP0  = 0xe0,

+  M_APP1  = 0xe1,

+  M_APP2  = 0xe2,

+  M_APP3  = 0xe3,

+  M_APP4  = 0xe4,

+  M_APP5  = 0xe5,

+  M_APP6  = 0xe6,

+  M_APP7  = 0xe7,

+  M_APP8  = 0xe8,

+  M_APP9  = 0xe9,

+  M_APP10 = 0xea,

+  M_APP11 = 0xeb,

+  M_APP12 = 0xec,

+  M_APP13 = 0xed,

+  M_APP14 = 0xee,

+  M_APP15 = 0xef,

+  

+  M_JPG0  = 0xf0,

+  M_JPG13 = 0xfd,

+  M_COM   = 0xfe,

+  

+  M_TEM   = 0x01,

+  

+  M_ERROR = 0x100

+} JPEG_MARKER;

+

+

+/*

+ * Macros for fetching data from the data source module.

+ *

+ * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect

+ * the current restart point; we update them only when we have reached a

+ * suitable place to restart if a suspension occurs.

+ */

+

+/* Declare and initialize local copies of input pointer/count */

+#define INPUT_VARS(cinfo)  \

+	struct jpeg_source_mgr * datasrc = (cinfo)->src;  \

+	const JOCTET * next_input_byte = datasrc->next_input_byte;  \

+	size_t bytes_in_buffer = datasrc->bytes_in_buffer

+

+/* Unload the local copies --- do this only at a restart boundary */

+#define INPUT_SYNC(cinfo)  \

+	( datasrc->next_input_byte = next_input_byte,  \

+	  datasrc->bytes_in_buffer = bytes_in_buffer )

+

+/* Reload the local copies --- seldom used except in MAKE_BYTE_AVAIL */

+#define INPUT_RELOAD(cinfo)  \

+	( next_input_byte = datasrc->next_input_byte,  \

+	  bytes_in_buffer = datasrc->bytes_in_buffer )

+

+/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available.

+ * Note we do *not* do INPUT_SYNC before calling fill_input_buffer,

+ * but we must reload the local copies after a successful fill.

+ */

+#define MAKE_BYTE_AVAIL(cinfo,action)  \

+	if (bytes_in_buffer == 0) {  \

+	  if (! (*datasrc->fill_input_buffer) (cinfo))  \

+	    { action; }  \

+	  INPUT_RELOAD(cinfo);  \

+	}  \

+	bytes_in_buffer--

+

+/* Read a byte into variable V.

+ * If must suspend, take the specified action (typically "return FALSE").

+ */

+#define INPUT_BYTE(cinfo,V,action)  \

+	MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \

+		  V = GETJOCTET(*next_input_byte++); )

+

+/* As above, but read two bytes interpreted as an unsigned 16-bit integer.

+ * V should be declared unsigned int or perhaps INT32.

+ */

+#define INPUT_2BYTES(cinfo,V,action)  \

+	MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \

+		  V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \

+		  MAKE_BYTE_AVAIL(cinfo,action); \

+		  V += GETJOCTET(*next_input_byte++); )

+

+

+/*

+ * Routines to process JPEG markers.

+ *

+ * Entry condition: JPEG marker itself has been read and its code saved

+ *   in cinfo->unread_marker; input restart point is just after the marker.

+ *

+ * Exit: if return TRUE, have read and processed any parameters, and have

+ *   updated the restart point to point after the parameters.

+ *   If return FALSE, was forced to suspend before reaching end of

+ *   marker parameters; restart point has not been moved.  Same routine

+ *   will be called again after application supplies more input data.

+ *

+ * This approach to suspension assumes that all of a marker's parameters can

+ * fit into a single input bufferload.  This should hold for "normal"

+ * markers.  Some COM/APPn markers might have large parameter segments,

+ * but we use skip_input_data to get past those, and thereby put the problem

+ * on the source manager's shoulders.

+ *

+ * Note that we don't bother to avoid duplicate trace messages if a

+ * suspension occurs within marker parameters.  Other side effects

+ * require more care.

+ */

+

+

+LOCAL boolean

+get_soi (j_decompress_ptr cinfo)

+/* Process an SOI marker */

+{

+  int i;

+  

+  TRACEMS(cinfo, 1, JTRC_SOI);

+

+  if (cinfo->marker->saw_SOI)

+    ERREXIT(cinfo, JERR_SOI_DUPLICATE);

+

+  /* Reset all parameters that are defined to be reset by SOI */

+

+  for (i = 0; i < NUM_ARITH_TBLS; i++) {

+    cinfo->arith_dc_L[i] = 0;

+    cinfo->arith_dc_U[i] = 1;

+    cinfo->arith_ac_K[i] = 5;

+  }

+  cinfo->restart_interval = 0;

+

+  /* Set initial assumptions for colorspace etc */

+

+  cinfo->jpeg_color_space = JCS_UNKNOWN;

+  cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */

+

+  cinfo->saw_JFIF_marker = FALSE;

+  cinfo->density_unit = 0;	/* set default JFIF APP0 values */

+  cinfo->X_density = 1;

+  cinfo->Y_density = 1;

+  cinfo->saw_Adobe_marker = FALSE;

+  cinfo->Adobe_transform = 0;

+

+  cinfo->marker->saw_SOI = TRUE;

+

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_sof (j_decompress_ptr cinfo, boolean is_prog, boolean is_arith)

+/* Process a SOFn marker */

+{

+  INT32 length;

+  int c, ci;

+  jpeg_component_info * compptr;

+  INPUT_VARS(cinfo);

+

+  cinfo->progressive_mode = is_prog;

+  cinfo->arith_code = is_arith;

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+

+  INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE);

+  INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE);

+  INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE);

+  INPUT_BYTE(cinfo, cinfo->num_components, return FALSE);

+

+  length -= 8;

+

+  TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker,

+	   (int) cinfo->image_width, (int) cinfo->image_height,

+	   cinfo->num_components);

+

+  if (cinfo->marker->saw_SOF)

+    ERREXIT(cinfo, JERR_SOF_DUPLICATE);

+

+  /* We don't support files in which the image height is initially specified */

+  /* as 0 and is later redefined by DNL.  As long as we have to check that,  */

+  /* might as well have a general sanity check. */

+  if (cinfo->image_height <= 0 || cinfo->image_width <= 0

+      || cinfo->num_components <= 0)

+    ERREXIT(cinfo, JERR_EMPTY_IMAGE);

+

+  if (length != (cinfo->num_components * 3))

+    ERREXIT(cinfo, JERR_BAD_LENGTH);

+

+  if (cinfo->comp_info == NULL)	/* do only once, even if suspend */

+    cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small)

+			((j_common_ptr) cinfo, JPOOL_IMAGE,

+			 cinfo->num_components * SIZEOF(jpeg_component_info));

+  

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    compptr->component_index = ci;

+    INPUT_BYTE(cinfo, compptr->component_id, return FALSE);

+    INPUT_BYTE(cinfo, c, return FALSE);

+    compptr->h_samp_factor = (c >> 4) & 15;

+    compptr->v_samp_factor = (c     ) & 15;

+    INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE);

+

+    TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT,

+	     compptr->component_id, compptr->h_samp_factor,

+	     compptr->v_samp_factor, compptr->quant_tbl_no);

+  }

+

+  cinfo->marker->saw_SOF = TRUE;

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_sos (j_decompress_ptr cinfo)

+/* Process a SOS marker */

+{

+  INT32 length;

+  int i, ci, n, c, cc;

+  jpeg_component_info * compptr;

+  INPUT_VARS(cinfo);

+

+  if (! cinfo->marker->saw_SOF)

+    ERREXIT(cinfo, JERR_SOS_NO_SOF);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+

+  INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */

+

+  if (length != (n * 2 + 6) || n < 1 || n > MAX_COMPS_IN_SCAN)

+    ERREXIT(cinfo, JERR_BAD_LENGTH);

+

+  TRACEMS1(cinfo, 1, JTRC_SOS, n);

+

+  cinfo->comps_in_scan = n;

+

+  /* Collect the component-spec parameters */

+

+  for (i = 0; i < n; i++) {

+    INPUT_BYTE(cinfo, cc, return FALSE);

+    INPUT_BYTE(cinfo, c, return FALSE);

+    

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      if (cc == compptr->component_id)

+	goto id_found;

+    }

+

+    ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc);

+

+  id_found:

+

+    cinfo->cur_comp_info[i] = compptr;

+    compptr->dc_tbl_no = (c >> 4) & 15;

+    compptr->ac_tbl_no = (c     ) & 15;

+    

+    TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc,

+	     compptr->dc_tbl_no, compptr->ac_tbl_no);

+  }

+

+  /* Collect the additional scan parameters Ss, Se, Ah/Al. */

+  INPUT_BYTE(cinfo, c, return FALSE);

+  cinfo->Ss = c;

+  INPUT_BYTE(cinfo, c, return FALSE);

+  cinfo->Se = c;

+  INPUT_BYTE(cinfo, c, return FALSE);

+  cinfo->Ah = (c >> 4) & 15;

+  cinfo->Al = (c     ) & 15;

+

+  TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se,

+	   cinfo->Ah, cinfo->Al);

+

+  /* Prepare to scan data & restart markers */

+  cinfo->marker->next_restart_num = 0;

+

+  /* Count another SOS marker */

+  cinfo->input_scan_number++;

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+METHODDEF boolean

+get_app0 (j_decompress_ptr cinfo)

+/* Process an APP0 marker */

+{

+#define JFIF_LEN 14

+  INT32 length;

+  UINT8 b[JFIF_LEN];

+  int buffp;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  length -= 2;

+

+  /* See if a JFIF APP0 marker is present */

+

+  if (length >= JFIF_LEN) {

+    for (buffp = 0; buffp < JFIF_LEN; buffp++)

+      INPUT_BYTE(cinfo, b[buffp], return FALSE);

+    length -= JFIF_LEN;

+

+    if (b[0]==0x4A && b[1]==0x46 && b[2]==0x49 && b[3]==0x46 && b[4]==0) {

+      /* Found JFIF APP0 marker: check version */

+      /* Major version must be 1, anything else signals an incompatible change.

+       * We used to treat this as an error, but now it's a nonfatal warning,

+       * because some bozo at Hijaak couldn't read the spec.

+       * Minor version should be 0..2, but process anyway if newer.

+       */

+      if (b[5] != 1)

+	WARNMS2(cinfo, JWRN_JFIF_MAJOR, b[5], b[6]);

+      else if (b[6] > 2)

+	TRACEMS2(cinfo, 1, JTRC_JFIF_MINOR, b[5], b[6]);

+      /* Save info */

+      cinfo->saw_JFIF_marker = TRUE;

+      cinfo->density_unit = b[7];

+      cinfo->X_density = (b[8] << 8) + b[9];

+      cinfo->Y_density = (b[10] << 8) + b[11];

+      TRACEMS3(cinfo, 1, JTRC_JFIF,

+	       cinfo->X_density, cinfo->Y_density, cinfo->density_unit);

+      if (b[12] | b[13])

+	TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL, b[12], b[13]);

+      if (length != ((INT32) b[12] * (INT32) b[13] * (INT32) 3))

+	TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) length);

+    } else {

+      /* Start of APP0 does not match "JFIF" */

+      TRACEMS1(cinfo, 1, JTRC_APP0, (int) length + JFIF_LEN);

+    }

+  } else {

+    /* Too short to be JFIF marker */

+    TRACEMS1(cinfo, 1, JTRC_APP0, (int) length);

+  }

+

+  INPUT_SYNC(cinfo);

+  if (length > 0)		/* skip any remaining data -- could be lots */

+    (*cinfo->src->skip_input_data) (cinfo, (long) length);

+

+  return TRUE;

+}

+

+

+METHODDEF boolean

+get_app14 (j_decompress_ptr cinfo)

+/* Process an APP14 marker */

+{

+#define ADOBE_LEN 12

+  INT32 length;

+  UINT8 b[ADOBE_LEN];

+  int buffp;

+  unsigned int version, flags0, flags1, transform;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  length -= 2;

+

+  /* See if an Adobe APP14 marker is present */

+

+  if (length >= ADOBE_LEN) {

+    for (buffp = 0; buffp < ADOBE_LEN; buffp++)

+      INPUT_BYTE(cinfo, b[buffp], return FALSE);

+    length -= ADOBE_LEN;

+

+    if (b[0]==0x41 && b[1]==0x64 && b[2]==0x6F && b[3]==0x62 && b[4]==0x65) {

+      /* Found Adobe APP14 marker */

+      version = (b[5] << 8) + b[6];

+      flags0 = (b[7] << 8) + b[8];

+      flags1 = (b[9] << 8) + b[10];

+      transform = b[11];

+      TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform);

+      cinfo->saw_Adobe_marker = TRUE;

+      cinfo->Adobe_transform = (UINT8) transform;

+    } else {

+      /* Start of APP14 does not match "Adobe" */

+      TRACEMS1(cinfo, 1, JTRC_APP14, (int) length + ADOBE_LEN);

+    }

+  } else {

+    /* Too short to be Adobe marker */

+    TRACEMS1(cinfo, 1, JTRC_APP14, (int) length);

+  }

+

+  INPUT_SYNC(cinfo);

+  if (length > 0)		/* skip any remaining data -- could be lots */

+    (*cinfo->src->skip_input_data) (cinfo, (long) length);

+

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_dac (j_decompress_ptr cinfo)

+/* Process a DAC marker */

+{

+  INT32 length;

+  int index, val;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  length -= 2;

+  

+  while (length > 0) {

+    INPUT_BYTE(cinfo, index, return FALSE);

+    INPUT_BYTE(cinfo, val, return FALSE);

+

+    length -= 2;

+

+    TRACEMS2(cinfo, 1, JTRC_DAC, index, val);

+

+    if (index < 0 || index >= (2*NUM_ARITH_TBLS))

+      ERREXIT1(cinfo, JERR_DAC_INDEX, index);

+

+    if (index >= NUM_ARITH_TBLS) { /* define AC table */

+      cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val;

+    } else {			/* define DC table */

+      cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F);

+      cinfo->arith_dc_U[index] = (UINT8) (val >> 4);

+      if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index])

+	ERREXIT1(cinfo, JERR_DAC_VALUE, val);

+    }

+  }

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_dht (j_decompress_ptr cinfo)

+/* Process a DHT marker */

+{

+  INT32 length;

+  UINT8 bits[17];

+  UINT8 huffval[256];

+  int i, index, count;

+  JHUFF_TBL **htblptr;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  length -= 2;

+  

+  while (length > 0) {

+    INPUT_BYTE(cinfo, index, return FALSE);

+

+    TRACEMS1(cinfo, 1, JTRC_DHT, index);

+      

+    bits[0] = 0;

+    count = 0;

+    for (i = 1; i <= 16; i++) {

+      INPUT_BYTE(cinfo, bits[i], return FALSE);

+      count += bits[i];

+    }

+

+    length -= 1 + 16;

+

+    TRACEMS8(cinfo, 2, JTRC_HUFFBITS,

+	     bits[1], bits[2], bits[3], bits[4],

+	     bits[5], bits[6], bits[7], bits[8]);

+    TRACEMS8(cinfo, 2, JTRC_HUFFBITS,

+	     bits[9], bits[10], bits[11], bits[12],

+	     bits[13], bits[14], bits[15], bits[16]);

+

+    if (count > 256 || ((INT32) count) > length)

+      ERREXIT(cinfo, JERR_DHT_COUNTS);

+

+    for (i = 0; i < count; i++)

+      INPUT_BYTE(cinfo, huffval[i], return FALSE);

+

+    length -= count;

+

+    if (index & 0x10) {		/* AC table definition */

+      index -= 0x10;

+      htblptr = &cinfo->ac_huff_tbl_ptrs[index];

+    } else {			/* DC table definition */

+      htblptr = &cinfo->dc_huff_tbl_ptrs[index];

+    }

+

+    if (index < 0 || index >= NUM_HUFF_TBLS)

+      ERREXIT1(cinfo, JERR_DHT_INDEX, index);

+

+    if (*htblptr == NULL)

+      *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);

+  

+    MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));

+    MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval));

+  }

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_dqt (j_decompress_ptr cinfo)

+/* Process a DQT marker */

+{

+  INT32 length;

+  int n, i, prec;

+  unsigned int tmp;

+  JQUANT_TBL *quant_ptr;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  length -= 2;

+

+  while (length > 0) {

+    INPUT_BYTE(cinfo, n, return FALSE);

+    prec = n >> 4;

+    n &= 0x0F;

+

+    TRACEMS2(cinfo, 1, JTRC_DQT, n, prec);

+

+    if (n >= NUM_QUANT_TBLS)

+      ERREXIT1(cinfo, JERR_DQT_INDEX, n);

+      

+    if (cinfo->quant_tbl_ptrs[n] == NULL)

+      cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo);

+    quant_ptr = cinfo->quant_tbl_ptrs[n];

+

+    for (i = 0; i < DCTSIZE2; i++) {

+      if (prec)

+	INPUT_2BYTES(cinfo, tmp, return FALSE);

+      else

+	INPUT_BYTE(cinfo, tmp, return FALSE);

+      quant_ptr->quantval[i] = (UINT16) tmp;

+    }

+

+    for (i = 0; i < DCTSIZE2; i += 8) {

+      TRACEMS8(cinfo, 2, JTRC_QUANTVALS,

+	       quant_ptr->quantval[i  ], quant_ptr->quantval[i+1],

+	       quant_ptr->quantval[i+2], quant_ptr->quantval[i+3],

+	       quant_ptr->quantval[i+4], quant_ptr->quantval[i+5],

+	       quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]);

+    }

+

+    length -= DCTSIZE2+1;

+    if (prec) length -= DCTSIZE2;

+  }

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+LOCAL boolean

+get_dri (j_decompress_ptr cinfo)

+/* Process a DRI marker */

+{

+  INT32 length;

+  unsigned int tmp;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  

+  if (length != 4)

+    ERREXIT(cinfo, JERR_BAD_LENGTH);

+

+  INPUT_2BYTES(cinfo, tmp, return FALSE);

+

+  TRACEMS1(cinfo, 1, JTRC_DRI, tmp);

+

+  cinfo->restart_interval = tmp;

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+METHODDEF boolean

+skip_variable (j_decompress_ptr cinfo)

+/* Skip over an unknown or uninteresting variable-length marker */

+{

+  INT32 length;

+  INPUT_VARS(cinfo);

+

+  INPUT_2BYTES(cinfo, length, return FALSE);

+  

+  TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length);

+

+  INPUT_SYNC(cinfo);		/* do before skip_input_data */

+  (*cinfo->src->skip_input_data) (cinfo, (long) length - 2L);

+

+  return TRUE;

+}

+

+

+/*

+ * Find the next JPEG marker, save it in cinfo->unread_marker.

+ * Returns FALSE if had to suspend before reaching a marker;

+ * in that case cinfo->unread_marker is unchanged.

+ *

+ * Note that the result might not be a valid marker code,

+ * but it will never be 0 or FF.

+ */

+

+LOCAL boolean

+next_marker (j_decompress_ptr cinfo)

+{

+  int c;

+  INPUT_VARS(cinfo);

+

+  for (;;) {

+    INPUT_BYTE(cinfo, c, return FALSE);

+    /* Skip any non-FF bytes.

+     * This may look a bit inefficient, but it will not occur in a valid file.

+     * We sync after each discarded byte so that a suspending data source

+     * can discard the byte from its buffer.

+     */

+    while (c != 0xFF) {

+      cinfo->marker->discarded_bytes++;

+      INPUT_SYNC(cinfo);

+      INPUT_BYTE(cinfo, c, return FALSE);

+    }

+    /* This loop swallows any duplicate FF bytes.  Extra FFs are legal as

+     * pad bytes, so don't count them in discarded_bytes.  We assume there

+     * will not be so many consecutive FF bytes as to overflow a suspending

+     * data source's input buffer.

+     */

+    do {

+      INPUT_BYTE(cinfo, c, return FALSE);

+    } while (c == 0xFF);

+    if (c != 0)

+      break;			/* found a valid marker, exit loop */

+    /* Reach here if we found a stuffed-zero data sequence (FF/00).

+     * Discard it and loop back to try again.

+     */

+    cinfo->marker->discarded_bytes += 2;

+    INPUT_SYNC(cinfo);

+  }

+

+  if (cinfo->marker->discarded_bytes != 0) {

+    WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c);

+    cinfo->marker->discarded_bytes = 0;

+  }

+

+  cinfo->unread_marker = c;

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+LOCAL boolean

+first_marker (j_decompress_ptr cinfo)

+/* Like next_marker, but used to obtain the initial SOI marker. */

+/* For this marker, we do not allow preceding garbage or fill; otherwise,

+ * we might well scan an entire input file before realizing it ain't JPEG.

+ * If an application wants to process non-JFIF files, it must seek to the

+ * SOI before calling the JPEG library.

+ */

+{

+  int c, c2;

+  INPUT_VARS(cinfo);

+

+  INPUT_BYTE(cinfo, c, return FALSE);

+  INPUT_BYTE(cinfo, c2, return FALSE);

+  if (c != 0xFF || c2 != (int) M_SOI)

+    ERREXIT2(cinfo, JERR_NO_SOI, c, c2);

+

+  cinfo->unread_marker = c2;

+

+  INPUT_SYNC(cinfo);

+  return TRUE;

+}

+

+

+/*

+ * Read markers until SOS or EOI.

+ *

+ * Returns same codes as are defined for jpeg_consume_input:

+ * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.

+ */

+

+METHODDEF int

+read_markers (j_decompress_ptr cinfo)

+{

+  /* Outer loop repeats once for each marker. */

+  for (;;) {

+    /* Collect the marker proper, unless we already did. */

+    /* NB: first_marker() enforces the requirement that SOI appear first. */

+    if (cinfo->unread_marker == 0) {

+      if (! cinfo->marker->saw_SOI) {

+	if (! first_marker(cinfo))

+	  return JPEG_SUSPENDED;

+      } else {

+	if (! next_marker(cinfo))

+	  return JPEG_SUSPENDED;

+      }

+    }

+    /* At this point cinfo->unread_marker contains the marker code and the

+     * input point is just past the marker proper, but before any parameters.

+     * A suspension will cause us to return with this state still true.

+     */

+    switch (cinfo->unread_marker) {

+    case M_SOI:

+      if (! get_soi(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+

+    case M_SOF0:		/* Baseline */

+    case M_SOF1:		/* Extended sequential, Huffman */

+      if (! get_sof(cinfo, FALSE, FALSE))

+	return JPEG_SUSPENDED;

+      break;

+

+    case M_SOF2:		/* Progressive, Huffman */

+      if (! get_sof(cinfo, TRUE, FALSE))

+	return JPEG_SUSPENDED;

+      break;

+

+    case M_SOF9:		/* Extended sequential, arithmetic */

+      if (! get_sof(cinfo, FALSE, TRUE))

+	return JPEG_SUSPENDED;

+      break;

+

+    case M_SOF10:		/* Progressive, arithmetic */

+      if (! get_sof(cinfo, TRUE, TRUE))

+	return JPEG_SUSPENDED;

+      break;

+

+    /* Currently unsupported SOFn types */

+    case M_SOF3:		/* Lossless, Huffman */

+    case M_SOF5:		/* Differential sequential, Huffman */

+    case M_SOF6:		/* Differential progressive, Huffman */

+    case M_SOF7:		/* Differential lossless, Huffman */

+    case M_JPG:			/* Reserved for JPEG extensions */

+    case M_SOF11:		/* Lossless, arithmetic */

+    case M_SOF13:		/* Differential sequential, arithmetic */

+    case M_SOF14:		/* Differential progressive, arithmetic */

+    case M_SOF15:		/* Differential lossless, arithmetic */

+      ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker);

+      break;

+

+    case M_SOS:

+      if (! get_sos(cinfo))

+	return JPEG_SUSPENDED;

+      cinfo->unread_marker = 0;	/* processed the marker */

+      return JPEG_REACHED_SOS;

+    

+    case M_EOI:

+      TRACEMS(cinfo, 1, JTRC_EOI);

+      cinfo->unread_marker = 0;	/* processed the marker */

+      return JPEG_REACHED_EOI;

+      

+    case M_DAC:

+      if (! get_dac(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+      

+    case M_DHT:

+      if (! get_dht(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+      

+    case M_DQT:

+      if (! get_dqt(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+      

+    case M_DRI:

+      if (! get_dri(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+      

+    case M_APP0:

+    case M_APP1:

+    case M_APP2:

+    case M_APP3:

+    case M_APP4:

+    case M_APP5:

+    case M_APP6:

+    case M_APP7:

+    case M_APP8:

+    case M_APP9:

+    case M_APP10:

+    case M_APP11:

+    case M_APP12:

+    case M_APP13:

+    case M_APP14:

+    case M_APP15:

+      if (! (*cinfo->marker->process_APPn[cinfo->unread_marker - (int) M_APP0]) (cinfo))

+	return JPEG_SUSPENDED;

+      break;

+      

+    case M_COM:

+      if (! (*cinfo->marker->process_COM) (cinfo))

+	return JPEG_SUSPENDED;

+      break;

+

+    case M_RST0:		/* these are all parameterless */

+    case M_RST1:

+    case M_RST2:

+    case M_RST3:

+    case M_RST4:

+    case M_RST5:

+    case M_RST6:

+    case M_RST7:

+    case M_TEM:

+      TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker);

+      break;

+

+    case M_DNL:			/* Ignore DNL ... perhaps the wrong thing */

+      if (! skip_variable(cinfo))

+	return JPEG_SUSPENDED;

+      break;

+

+    default:			/* must be DHP, EXP, JPGn, or RESn */

+      /* For now, we treat the reserved markers as fatal errors since they are

+       * likely to be used to signal incompatible JPEG Part 3 extensions.

+       * Once the JPEG 3 version-number marker is well defined, this code

+       * ought to change!

+       */

+      ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);

+      break;

+    }

+    /* Successfully processed marker, so reset state variable */

+    cinfo->unread_marker = 0;

+  } /* end loop */

+}

+

+

+/*

+ * Read a restart marker, which is expected to appear next in the datastream;

+ * if the marker is not there, take appropriate recovery action.

+ * Returns FALSE if suspension is required.

+ *

+ * This is called by the entropy decoder after it has read an appropriate

+ * number of MCUs.  cinfo->unread_marker may be nonzero if the entropy decoder

+ * has already read a marker from the data source.  Under normal conditions

+ * cinfo->unread_marker will be reset to 0 before returning; if not reset,

+ * it holds a marker which the decoder will be unable to read past.

+ */

+

+METHODDEF boolean

+read_restart_marker (j_decompress_ptr cinfo)

+{

+  /* Obtain a marker unless we already did. */

+  /* Note that next_marker will complain if it skips any data. */

+  if (cinfo->unread_marker == 0) {

+    if (! next_marker(cinfo))

+      return FALSE;

+  }

+

+  if (cinfo->unread_marker ==

+      ((int) M_RST0 + cinfo->marker->next_restart_num)) {

+    /* Normal case --- swallow the marker and let entropy decoder continue */

+    TRACEMS1(cinfo, 2, JTRC_RST, cinfo->marker->next_restart_num);

+    cinfo->unread_marker = 0;

+  } else {

+    /* Uh-oh, the restart markers have been messed up. */

+    /* Let the data source manager determine how to resync. */

+    if (! (*cinfo->src->resync_to_restart) (cinfo,

+					    cinfo->marker->next_restart_num))

+      return FALSE;

+  }

+

+  /* Update next-restart state */

+  cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7;

+

+  return TRUE;

+}

+

+

+/*

+ * This is the default resync_to_restart method for data source managers

+ * to use if they don't have any better approach.  Some data source managers

+ * may be able to back up, or may have additional knowledge about the data

+ * which permits a more intelligent recovery strategy; such managers would

+ * presumably supply their own resync method.

+ *

+ * read_restart_marker calls resync_to_restart if it finds a marker other than

+ * the restart marker it was expecting.  (This code is *not* used unless

+ * a nonzero restart interval has been declared.)  cinfo->unread_marker is

+ * the marker code actually found (might be anything, except 0 or FF).

+ * The desired restart marker number (0..7) is passed as a parameter.

+ * This routine is supposed to apply whatever error recovery strategy seems

+ * appropriate in order to position the input stream to the next data segment.

+ * Note that cinfo->unread_marker is treated as a marker appearing before

+ * the current data-source input point; usually it should be reset to zero

+ * before returning.

+ * Returns FALSE if suspension is required.

+ *

+ * This implementation is substantially constrained by wanting to treat the

+ * input as a data stream; this means we can't back up.  Therefore, we have

+ * only the following actions to work with:

+ *   1. Simply discard the marker and let the entropy decoder resume at next

+ *      byte of file.

+ *   2. Read forward until we find another marker, discarding intervening

+ *      data.  (In theory we could look ahead within the current bufferload,

+ *      without having to discard data if we don't find the desired marker.

+ *      This idea is not implemented here, in part because it makes behavior

+ *      dependent on buffer size and chance buffer-boundary positions.)

+ *   3. Leave the marker unread (by failing to zero cinfo->unread_marker).

+ *      This will cause the entropy decoder to process an empty data segment,

+ *      inserting dummy zeroes, and then we will reprocess the marker.

+ *

+ * #2 is appropriate if we think the desired marker lies ahead, while #3 is

+ * appropriate if the found marker is a future restart marker (indicating

+ * that we have missed the desired restart marker, probably because it got

+ * corrupted).

+ * We apply #2 or #3 if the found marker is a restart marker no more than

+ * two counts behind or ahead of the expected one.  We also apply #2 if the

+ * found marker is not a legal JPEG marker code (it's certainly bogus data).

+ * If the found marker is a restart marker more than 2 counts away, we do #1

+ * (too much risk that the marker is erroneous; with luck we will be able to

+ * resync at some future point).

+ * For any valid non-restart JPEG marker, we apply #3.  This keeps us from

+ * overrunning the end of a scan.  An implementation limited to single-scan

+ * files might find it better to apply #2 for markers other than EOI, since

+ * any other marker would have to be bogus data in that case.

+ */

+

+GLOBAL boolean

+jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired)

+{

+  int marker = cinfo->unread_marker;

+  int action = 1;

+  

+  /* Always put up a warning. */

+  WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired);

+  

+  /* Outer loop handles repeated decision after scanning forward. */

+  for (;;) {

+    if (marker < (int) M_SOF0)

+      action = 2;		/* invalid marker */

+    else if (marker < (int) M_RST0 || marker > (int) M_RST7)

+      action = 3;		/* valid non-restart marker */

+    else {

+      if (marker == ((int) M_RST0 + ((desired+1) & 7)) ||

+	  marker == ((int) M_RST0 + ((desired+2) & 7)))

+	action = 3;		/* one of the next two expected restarts */

+      else if (marker == ((int) M_RST0 + ((desired-1) & 7)) ||

+	       marker == ((int) M_RST0 + ((desired-2) & 7)))

+	action = 2;		/* a prior restart, so advance */

+      else

+	action = 1;		/* desired restart or too far away */

+    }

+    TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action);

+    switch (action) {

+    case 1:

+      /* Discard marker and let entropy decoder resume processing. */

+      cinfo->unread_marker = 0;

+      return TRUE;

+    case 2:

+      /* Scan to the next marker, and repeat the decision loop. */

+      if (! next_marker(cinfo))

+	return FALSE;

+      marker = cinfo->unread_marker;

+      break;

+    case 3:

+      /* Return without advancing past this marker. */

+      /* Entropy decoder will be forced to process an empty segment. */

+      return TRUE;

+    }

+  } /* end loop */

+}

+

+

+/*

+ * Reset marker processing state to begin a fresh datastream.

+ */

+

+METHODDEF void

+reset_marker_reader (j_decompress_ptr cinfo)

+{

+  cinfo->comp_info = NULL;		/* until allocated by get_sof */

+  cinfo->input_scan_number = 0;		/* no SOS seen yet */

+  cinfo->unread_marker = 0;		/* no pending marker */

+  cinfo->marker->saw_SOI = FALSE;	/* set internal state too */

+  cinfo->marker->saw_SOF = FALSE;

+  cinfo->marker->discarded_bytes = 0;

+}

+

+

+/*

+ * Initialize the marker reader module.

+ * This is called only once, when the decompression object is created.

+ */

+

+GLOBAL void

+jinit_marker_reader (j_decompress_ptr cinfo)

+{

+  int i;

+

+  /* Create subobject in permanent pool */

+  cinfo->marker = (struct jpeg_marker_reader *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

+				SIZEOF(struct jpeg_marker_reader));

+  /* Initialize method pointers */

+  cinfo->marker->reset_marker_reader = reset_marker_reader;

+  cinfo->marker->read_markers = read_markers;

+  cinfo->marker->read_restart_marker = read_restart_marker;

+  cinfo->marker->process_COM = skip_variable;

+  for (i = 0; i < 16; i++)

+    cinfo->marker->process_APPn[i] = skip_variable;

+  cinfo->marker->process_APPn[0] = get_app0;

+  cinfo->marker->process_APPn[14] = get_app14;

+  /* Reset marker processing state */

+  reset_marker_reader(cinfo);

+}

diff --git a/code/jpeg-6/jdmaster.c b/code/jpeg-6/jdmaster.c
new file mode 100755
index 0000000..64f730f
--- /dev/null
+++ b/code/jpeg-6/jdmaster.c
@@ -0,0 +1,557 @@
+/*

+ * jdmaster.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains master control logic for the JPEG decompressor.

+ * These routines are concerned with selecting the modules to be executed

+ * and with determining the number of passes and the work to be done in each

+ * pass.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private state */

+

+typedef struct {

+  struct jpeg_decomp_master pub; /* public fields */

+

+  int pass_number;		/* # of passes completed */

+

+  boolean using_merged_upsample; /* TRUE if using merged upsample/cconvert */

+

+  /* Saved references to initialized quantizer modules,

+   * in case we need to switch modes.

+   */

+  struct jpeg_color_quantizer * quantizer_1pass;

+  struct jpeg_color_quantizer * quantizer_2pass;

+} my_decomp_master;

+

+typedef my_decomp_master * my_master_ptr;

+

+

+/*

+ * Determine whether merged upsample/color conversion should be used.

+ * CRUCIAL: this must match the actual capabilities of jdmerge.c!

+ */

+

+LOCAL boolean

+use_merged_upsample (j_decompress_ptr cinfo)

+{

+#ifdef UPSAMPLE_MERGING_SUPPORTED

+  /* Merging is the equivalent of plain box-filter upsampling */

+  if (cinfo->do_fancy_upsampling || cinfo->CCIR601_sampling)

+    return FALSE;

+  /* jdmerge.c only supports YCC=>RGB color conversion */

+  if (cinfo->jpeg_color_space != JCS_YCbCr || cinfo->num_components != 3 ||

+      cinfo->out_color_space != JCS_RGB ||

+      cinfo->out_color_components != RGB_PIXELSIZE)

+    return FALSE;

+  /* and it only handles 2h1v or 2h2v sampling ratios */

+  if (cinfo->comp_info[0].h_samp_factor != 2 ||

+      cinfo->comp_info[1].h_samp_factor != 1 ||

+      cinfo->comp_info[2].h_samp_factor != 1 ||

+      cinfo->comp_info[0].v_samp_factor >  2 ||

+      cinfo->comp_info[1].v_samp_factor != 1 ||

+      cinfo->comp_info[2].v_samp_factor != 1)

+    return FALSE;

+  /* furthermore, it doesn't work if we've scaled the IDCTs differently */

+  if (cinfo->comp_info[0].DCT_scaled_size != cinfo->min_DCT_scaled_size ||

+      cinfo->comp_info[1].DCT_scaled_size != cinfo->min_DCT_scaled_size ||

+      cinfo->comp_info[2].DCT_scaled_size != cinfo->min_DCT_scaled_size)

+    return FALSE;

+  /* ??? also need to test for upsample-time rescaling, when & if supported */

+  return TRUE;			/* by golly, it'll work... */

+#else

+  return FALSE;

+#endif

+}

+

+

+/*

+ * Compute output image dimensions and related values.

+ * NOTE: this is exported for possible use by application.

+ * Hence it mustn't do anything that can't be done twice.

+ * Also note that it may be called before the master module is initialized!

+ */

+

+GLOBAL void

+jpeg_calc_output_dimensions (j_decompress_ptr cinfo)

+/* Do computations that are needed before master selection phase */

+{

+#if 0	// JDC: commented out to remove warning

+  int ci;

+  jpeg_component_info *compptr;

+#endif

+

+  /* Prevent application from calling me at wrong times */

+  if (cinfo->global_state != DSTATE_READY)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+#ifdef IDCT_SCALING_SUPPORTED

+

+  /* Compute actual output image dimensions and DCT scaling choices. */

+  if (cinfo->scale_num * 8 <= cinfo->scale_denom) {

+    /* Provide 1/8 scaling */

+    cinfo->output_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width, 8L);

+    cinfo->output_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height, 8L);

+    cinfo->min_DCT_scaled_size = 1;

+  } else if (cinfo->scale_num * 4 <= cinfo->scale_denom) {

+    /* Provide 1/4 scaling */

+    cinfo->output_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width, 4L);

+    cinfo->output_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height, 4L);

+    cinfo->min_DCT_scaled_size = 2;

+  } else if (cinfo->scale_num * 2 <= cinfo->scale_denom) {

+    /* Provide 1/2 scaling */

+    cinfo->output_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width, 2L);

+    cinfo->output_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height, 2L);

+    cinfo->min_DCT_scaled_size = 4;

+  } else {

+    /* Provide 1/1 scaling */

+    cinfo->output_width = cinfo->image_width;

+    cinfo->output_height = cinfo->image_height;

+    cinfo->min_DCT_scaled_size = DCTSIZE;

+  }

+  /* In selecting the actual DCT scaling for each component, we try to

+   * scale up the chroma components via IDCT scaling rather than upsampling.

+   * This saves time if the upsampler gets to use 1:1 scaling.

+   * Note this code assumes that the supported DCT scalings are powers of 2.

+   */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    int ssize = cinfo->min_DCT_scaled_size;

+    while (ssize < DCTSIZE &&

+	   (compptr->h_samp_factor * ssize * 2 <=

+	    cinfo->max_h_samp_factor * cinfo->min_DCT_scaled_size) &&

+	   (compptr->v_samp_factor * ssize * 2 <=

+	    cinfo->max_v_samp_factor * cinfo->min_DCT_scaled_size)) {

+      ssize = ssize * 2;

+    }

+    compptr->DCT_scaled_size = ssize;

+  }

+

+  /* Recompute downsampled dimensions of components;

+   * application needs to know these if using raw downsampled data.

+   */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Size in samples, after IDCT scaling */

+    compptr->downsampled_width = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_width *

+		    (long) (compptr->h_samp_factor * compptr->DCT_scaled_size),

+		    (long) (cinfo->max_h_samp_factor * DCTSIZE));

+    compptr->downsampled_height = (JDIMENSION)

+      jdiv_round_up((long) cinfo->image_height *

+		    (long) (compptr->v_samp_factor * compptr->DCT_scaled_size),

+		    (long) (cinfo->max_v_samp_factor * DCTSIZE));

+  }

+

+#else /* !IDCT_SCALING_SUPPORTED */

+

+  /* Hardwire it to "no scaling" */

+  cinfo->output_width = cinfo->image_width;

+  cinfo->output_height = cinfo->image_height;

+  /* jdinput.c has already initialized DCT_scaled_size to DCTSIZE,

+   * and has computed unscaled downsampled_width and downsampled_height.

+   */

+

+#endif /* IDCT_SCALING_SUPPORTED */

+

+  /* Report number of components in selected colorspace. */

+  /* Probably this should be in the color conversion module... */

+  switch (cinfo->out_color_space) {

+  case JCS_GRAYSCALE:

+    cinfo->out_color_components = 1;

+    break;

+  case JCS_RGB:

+#if RGB_PIXELSIZE != 3

+    cinfo->out_color_components = RGB_PIXELSIZE;

+    break;

+#endif /* else share code with YCbCr */

+  case JCS_YCbCr:

+    cinfo->out_color_components = 3;

+    break;

+  case JCS_CMYK:

+  case JCS_YCCK:

+    cinfo->out_color_components = 4;

+    break;

+  default:			/* else must be same colorspace as in file */

+    cinfo->out_color_components = cinfo->num_components;

+    break;

+  }

+  cinfo->output_components = (cinfo->quantize_colors ? 1 :

+			      cinfo->out_color_components);

+

+  /* See if upsampler will want to emit more than one row at a time */

+  if (use_merged_upsample(cinfo))

+    cinfo->rec_outbuf_height = cinfo->max_v_samp_factor;

+  else

+    cinfo->rec_outbuf_height = 1;

+}

+

+

+/*

+ * Several decompression processes need to range-limit values to the range

+ * 0..MAXJSAMPLE; the input value may fall somewhat outside this range

+ * due to noise introduced by quantization, roundoff error, etc.  These

+ * processes are inner loops and need to be as fast as possible.  On most

+ * machines, particularly CPUs with pipelines or instruction prefetch,

+ * a (subscript-check-less) C table lookup

+ *		x = sample_range_limit[x];

+ * is faster than explicit tests

+ *		if (x < 0)  x = 0;

+ *		else if (x > MAXJSAMPLE)  x = MAXJSAMPLE;

+ * These processes all use a common table prepared by the routine below.

+ *

+ * For most steps we can mathematically guarantee that the initial value

+ * of x is within MAXJSAMPLE+1 of the legal range, so a table running from

+ * -(MAXJSAMPLE+1) to 2*MAXJSAMPLE+1 is sufficient.  But for the initial

+ * limiting step (just after the IDCT), a wildly out-of-range value is 

+ * possible if the input data is corrupt.  To avoid any chance of indexing

+ * off the end of memory and getting a bad-pointer trap, we perform the

+ * post-IDCT limiting thus:

+ *		x = range_limit[x & MASK];

+ * where MASK is 2 bits wider than legal sample data, ie 10 bits for 8-bit

+ * samples.  Under normal circumstances this is more than enough range and

+ * a correct output will be generated; with bogus input data the mask will

+ * cause wraparound, and we will safely generate a bogus-but-in-range output.

+ * For the post-IDCT step, we want to convert the data from signed to unsigned

+ * representation by adding CENTERJSAMPLE at the same time that we limit it.

+ * So the post-IDCT limiting table ends up looking like this:

+ *   CENTERJSAMPLE,CENTERJSAMPLE+1,...,MAXJSAMPLE,

+ *   MAXJSAMPLE (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),

+ *   0          (repeat 2*(MAXJSAMPLE+1)-CENTERJSAMPLE times),

+ *   0,1,...,CENTERJSAMPLE-1

+ * Negative inputs select values from the upper half of the table after

+ * masking.

+ *

+ * We can save some space by overlapping the start of the post-IDCT table

+ * with the simpler range limiting table.  The post-IDCT table begins at

+ * sample_range_limit + CENTERJSAMPLE.

+ *

+ * Note that the table is allocated in near data space on PCs; it's small

+ * enough and used often enough to justify this.

+ */

+

+LOCAL void

+prepare_range_limit_table (j_decompress_ptr cinfo)

+/* Allocate and fill in the sample_range_limit table */

+{

+  JSAMPLE * table;

+  int i;

+

+  table = (JSAMPLE *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+		(5 * (MAXJSAMPLE+1) + CENTERJSAMPLE) * SIZEOF(JSAMPLE));

+  table += (MAXJSAMPLE+1);	/* allow negative subscripts of simple table */

+  cinfo->sample_range_limit = table;

+  /* First segment of "simple" table: limit[x] = 0 for x < 0 */

+  MEMZERO(table - (MAXJSAMPLE+1), (MAXJSAMPLE+1) * SIZEOF(JSAMPLE));

+  /* Main part of "simple" table: limit[x] = x */

+  for (i = 0; i <= MAXJSAMPLE; i++)

+    table[i] = (JSAMPLE) i;

+  table += CENTERJSAMPLE;	/* Point to where post-IDCT table starts */

+  /* End of simple table, rest of first half of post-IDCT table */

+  for (i = CENTERJSAMPLE; i < 2*(MAXJSAMPLE+1); i++)

+    table[i] = MAXJSAMPLE;

+  /* Second half of post-IDCT table */

+  MEMZERO(table + (2 * (MAXJSAMPLE+1)),

+	  (2 * (MAXJSAMPLE+1) - CENTERJSAMPLE) * SIZEOF(JSAMPLE));

+  MEMCOPY(table + (4 * (MAXJSAMPLE+1) - CENTERJSAMPLE),

+	  cinfo->sample_range_limit, CENTERJSAMPLE * SIZEOF(JSAMPLE));

+}

+

+

+/*

+ * Master selection of decompression modules.

+ * This is done once at jpeg_start_decompress time.  We determine

+ * which modules will be used and give them appropriate initialization calls.

+ * We also initialize the decompressor input side to begin consuming data.

+ *

+ * Since jpeg_read_header has finished, we know what is in the SOF

+ * and (first) SOS markers.  We also have all the application parameter

+ * settings.

+ */

+

+LOCAL void

+master_selection (j_decompress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+  boolean use_c_buffer;

+  long samplesperrow;

+  JDIMENSION jd_samplesperrow;

+

+  /* Initialize dimensions and other stuff */

+  jpeg_calc_output_dimensions(cinfo);

+  prepare_range_limit_table(cinfo);

+

+  /* Width of an output scanline must be representable as JDIMENSION. */

+  samplesperrow = (long) cinfo->output_width * (long) cinfo->out_color_components;

+  jd_samplesperrow = (JDIMENSION) samplesperrow;

+  if ((long) jd_samplesperrow != samplesperrow)

+    ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);

+

+  /* Initialize my private state */

+  master->pass_number = 0;

+  master->using_merged_upsample = use_merged_upsample(cinfo);

+

+  /* Color quantizer selection */

+  master->quantizer_1pass = NULL;

+  master->quantizer_2pass = NULL;

+  /* No mode changes if not using buffered-image mode. */

+  if (! cinfo->quantize_colors || ! cinfo->buffered_image) {

+    cinfo->enable_1pass_quant = FALSE;

+    cinfo->enable_external_quant = FALSE;

+    cinfo->enable_2pass_quant = FALSE;

+  }

+  if (cinfo->quantize_colors) {

+    if (cinfo->raw_data_out)

+      ERREXIT(cinfo, JERR_NOTIMPL);

+    /* 2-pass quantizer only works in 3-component color space. */

+    if (cinfo->out_color_components != 3) {

+      cinfo->enable_1pass_quant = TRUE;

+      cinfo->enable_external_quant = FALSE;

+      cinfo->enable_2pass_quant = FALSE;

+      cinfo->colormap = NULL;

+    } else if (cinfo->colormap != NULL) {

+      cinfo->enable_external_quant = TRUE;

+    } else if (cinfo->two_pass_quantize) {

+      cinfo->enable_2pass_quant = TRUE;

+    } else {

+      cinfo->enable_1pass_quant = TRUE;

+    }

+

+    if (cinfo->enable_1pass_quant) {

+#ifdef QUANT_1PASS_SUPPORTED

+      jinit_1pass_quantizer(cinfo);

+      master->quantizer_1pass = cinfo->cquantize;

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    }

+

+    /* We use the 2-pass code to map to external colormaps. */

+    if (cinfo->enable_2pass_quant || cinfo->enable_external_quant) {

+#ifdef QUANT_2PASS_SUPPORTED

+      jinit_2pass_quantizer(cinfo);

+      master->quantizer_2pass = cinfo->cquantize;

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    }

+    /* If both quantizers are initialized, the 2-pass one is left active;

+     * this is necessary for starting with quantization to an external map.

+     */

+  }

+

+  /* Post-processing: in particular, color conversion first */

+  if (! cinfo->raw_data_out) {

+    if (master->using_merged_upsample) {

+#ifdef UPSAMPLE_MERGING_SUPPORTED

+      jinit_merged_upsampler(cinfo); /* does color conversion too */

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    } else {

+      jinit_color_deconverter(cinfo);

+      jinit_upsampler(cinfo);

+    }

+    jinit_d_post_controller(cinfo, cinfo->enable_2pass_quant);

+  }

+  /* Inverse DCT */

+  jinit_inverse_dct(cinfo);

+  /* Entropy decoding: either Huffman or arithmetic coding. */

+  if (cinfo->arith_code) {

+    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);

+  } else {

+    if (cinfo->progressive_mode) {

+#ifdef D_PROGRESSIVE_SUPPORTED

+      jinit_phuff_decoder(cinfo);

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    } else

+      jinit_huff_decoder(cinfo);

+  }

+

+  /* Initialize principal buffer controllers. */

+  use_c_buffer = cinfo->inputctl->has_multiple_scans || cinfo->buffered_image;

+  jinit_d_coef_controller(cinfo, use_c_buffer);

+

+  if (! cinfo->raw_data_out)

+    jinit_d_main_controller(cinfo, FALSE /* never need full buffer here */);

+

+  /* We can now tell the memory manager to allocate virtual arrays. */

+  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);

+

+  /* Initialize input side of decompressor to consume first scan. */

+  (*cinfo->inputctl->start_input_pass) (cinfo);

+

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+  /* If jpeg_start_decompress will read the whole file, initialize

+   * progress monitoring appropriately.  The input step is counted

+   * as one pass.

+   */

+  if (cinfo->progress != NULL && ! cinfo->buffered_image &&

+      cinfo->inputctl->has_multiple_scans) {

+    int nscans;

+    /* Estimate number of scans to set pass_limit. */

+    if (cinfo->progressive_mode) {

+      /* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */

+      nscans = 2 + 3 * cinfo->num_components;

+    } else {

+      /* For a nonprogressive multiscan file, estimate 1 scan per component. */

+      nscans = cinfo->num_components;

+    }

+    cinfo->progress->pass_counter = 0L;

+    cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans;

+    cinfo->progress->completed_passes = 0;

+    cinfo->progress->total_passes = (cinfo->enable_2pass_quant ? 3 : 2);

+    /* Count the input pass as done */

+    master->pass_number++;

+  }

+#endif /* D_MULTISCAN_FILES_SUPPORTED */

+}

+

+

+/*

+ * Per-pass setup.

+ * This is called at the beginning of each output pass.  We determine which

+ * modules will be active during this pass and give them appropriate

+ * start_pass calls.  We also set is_dummy_pass to indicate whether this

+ * is a "real" output pass or a dummy pass for color quantization.

+ * (In the latter case, jdapi.c will crank the pass to completion.)

+ */

+

+METHODDEF void

+prepare_for_output_pass (j_decompress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+

+  if (master->pub.is_dummy_pass) {

+#ifdef QUANT_2PASS_SUPPORTED

+    /* Final pass of 2-pass quantization */

+    master->pub.is_dummy_pass = FALSE;

+    (*cinfo->cquantize->start_pass) (cinfo, FALSE);

+    (*cinfo->post->start_pass) (cinfo, JBUF_CRANK_DEST);

+    (*cinfo->main->start_pass) (cinfo, JBUF_CRANK_DEST);

+#else

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif /* QUANT_2PASS_SUPPORTED */

+  } else {

+    if (cinfo->quantize_colors && cinfo->colormap == NULL) {

+      /* Select new quantization method */

+      if (cinfo->two_pass_quantize && cinfo->enable_2pass_quant) {

+	cinfo->cquantize = master->quantizer_2pass;

+	master->pub.is_dummy_pass = TRUE;

+      } else if (cinfo->enable_1pass_quant) {

+	cinfo->cquantize = master->quantizer_1pass;

+      } else {

+	ERREXIT(cinfo, JERR_MODE_CHANGE);

+      }

+    }

+    (*cinfo->idct->start_pass) (cinfo);

+    (*cinfo->coef->start_output_pass) (cinfo);

+    if (! cinfo->raw_data_out) {

+      if (! master->using_merged_upsample)

+	(*cinfo->cconvert->start_pass) (cinfo);

+      (*cinfo->upsample->start_pass) (cinfo);

+      if (cinfo->quantize_colors)

+	(*cinfo->cquantize->start_pass) (cinfo, master->pub.is_dummy_pass);

+      (*cinfo->post->start_pass) (cinfo,

+	    (master->pub.is_dummy_pass ? JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));

+      (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);

+    }

+  }

+

+  /* Set up progress monitor's pass info if present */

+  if (cinfo->progress != NULL) {

+    cinfo->progress->completed_passes = master->pass_number;

+    cinfo->progress->total_passes = master->pass_number +

+				    (master->pub.is_dummy_pass ? 2 : 1);

+    /* In buffered-image mode, we assume one more output pass if EOI not

+     * yet reached, but no more passes if EOI has been reached.

+     */

+    if (cinfo->buffered_image && ! cinfo->inputctl->eoi_reached) {

+      cinfo->progress->total_passes += (cinfo->enable_2pass_quant ? 2 : 1);

+    }

+  }

+}

+

+

+/*

+ * Finish up at end of an output pass.

+ */

+

+METHODDEF void

+finish_output_pass (j_decompress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+

+  if (cinfo->quantize_colors)

+    (*cinfo->cquantize->finish_pass) (cinfo);

+  master->pass_number++;

+}

+

+

+#ifdef D_MULTISCAN_FILES_SUPPORTED

+

+/*

+ * Switch to a new external colormap between output passes.

+ */

+

+GLOBAL void

+jpeg_new_colormap (j_decompress_ptr cinfo)

+{

+  my_master_ptr master = (my_master_ptr) cinfo->master;

+

+  /* Prevent application from calling me at wrong times */

+  if (cinfo->global_state != DSTATE_BUFIMAGE)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  if (cinfo->quantize_colors && cinfo->enable_external_quant &&

+      cinfo->colormap != NULL) {

+    /* Select 2-pass quantizer for external colormap use */

+    cinfo->cquantize = master->quantizer_2pass;

+    /* Notify quantizer of colormap change */

+    (*cinfo->cquantize->new_color_map) (cinfo);

+    master->pub.is_dummy_pass = FALSE; /* just in case */

+  } else

+    ERREXIT(cinfo, JERR_MODE_CHANGE);

+}

+

+#endif /* D_MULTISCAN_FILES_SUPPORTED */

+

+

+/*

+ * Initialize master decompression control and select active modules.

+ * This is performed at the start of jpeg_start_decompress.

+ */

+

+GLOBAL void

+jinit_master_decompress (j_decompress_ptr cinfo)

+{

+  my_master_ptr master;

+

+  master = (my_master_ptr)

+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				  SIZEOF(my_decomp_master));

+  cinfo->master = (struct jpeg_decomp_master *) master;

+  master->pub.prepare_for_output_pass = prepare_for_output_pass;

+  master->pub.finish_output_pass = finish_output_pass;

+

+  master->pub.is_dummy_pass = FALSE;

+

+  master_selection(cinfo);

+}

diff --git a/code/jpeg-6/jdmerge.c b/code/jpeg-6/jdmerge.c
new file mode 100755
index 0000000..cc81640
--- /dev/null
+++ b/code/jpeg-6/jdmerge.c
@@ -0,0 +1,400 @@
+/*

+ * jdmerge.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains code for merged upsampling/color conversion.

+ *

+ * This file combines functions from jdsample.c and jdcolor.c;

+ * read those files first to understand what's going on.

+ *

+ * When the chroma components are to be upsampled by simple replication

+ * (ie, box filtering), we can save some work in color conversion by

+ * calculating all the output pixels corresponding to a pair of chroma

+ * samples at one time.  In the conversion equations

+ *	R = Y           + K1 * Cr

+ *	G = Y + K2 * Cb + K3 * Cr

+ *	B = Y + K4 * Cb

+ * only the Y term varies among the group of pixels corresponding to a pair

+ * of chroma samples, so the rest of the terms can be calculated just once.

+ * At typical sampling ratios, this eliminates half or three-quarters of the

+ * multiplications needed for color conversion.

+ *

+ * This file currently provides implementations for the following cases:

+ *	YCbCr => RGB color conversion only.

+ *	Sampling ratios of 2h1v or 2h2v.

+ *	No scaling needed at upsample time.

+ *	Corner-aligned (non-CCIR601) sampling alignment.

+ * Other special cases could be added, but in most applications these are

+ * the only common cases.  (For uncommon cases we fall back on the more

+ * general code in jdsample.c and jdcolor.c.)

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+#ifdef UPSAMPLE_MERGING_SUPPORTED

+

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_upsampler pub;	/* public fields */

+

+  /* Pointer to routine to do actual upsampling/conversion of one row group */

+  JMETHOD(void, upmethod, (j_decompress_ptr cinfo,

+			   JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,

+			   JSAMPARRAY output_buf));

+

+  /* Private state for YCC->RGB conversion */

+  int * Cr_r_tab;		/* => table for Cr to R conversion */

+  int * Cb_b_tab;		/* => table for Cb to B conversion */

+  INT32 * Cr_g_tab;		/* => table for Cr to G conversion */

+  INT32 * Cb_g_tab;		/* => table for Cb to G conversion */

+

+  /* For 2:1 vertical sampling, we produce two output rows at a time.

+   * We need a "spare" row buffer to hold the second output row if the

+   * application provides just a one-row buffer; we also use the spare

+   * to discard the dummy last row if the image height is odd.

+   */

+  JSAMPROW spare_row;

+  boolean spare_full;		/* T if spare buffer is occupied */

+

+  JDIMENSION out_row_width;	/* samples per output row */

+  JDIMENSION rows_to_go;	/* counts rows remaining in image */

+} my_upsampler;

+

+typedef my_upsampler * my_upsample_ptr;

+

+#define SCALEBITS	16	/* speediest right-shift on some machines */

+#define ONE_HALF	((INT32) 1 << (SCALEBITS-1))

+#define FIX(x)		((INT32) ((x) * (1L<<SCALEBITS) + 0.5))

+

+

+/*

+ * Initialize tables for YCC->RGB colorspace conversion.

+ * This is taken directly from jdcolor.c; see that file for more info.

+ */

+

+LOCAL void

+build_ycc_rgb_table (j_decompress_ptr cinfo)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  int i;

+  INT32 x;

+  SHIFT_TEMPS

+

+  upsample->Cr_r_tab = (int *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(int));

+  upsample->Cb_b_tab = (int *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(int));

+  upsample->Cr_g_tab = (INT32 *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(INT32));

+  upsample->Cb_g_tab = (INT32 *)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				(MAXJSAMPLE+1) * SIZEOF(INT32));

+

+  for (i = 0, x = -CENTERJSAMPLE; i <= MAXJSAMPLE; i++, x++) {

+    /* i is the actual input pixel value, in the range 0..MAXJSAMPLE */

+    /* The Cb or Cr value we are thinking of is x = i - CENTERJSAMPLE */

+    /* Cr=>R value is nearest int to 1.40200 * x */

+    upsample->Cr_r_tab[i] = (int)

+		    RIGHT_SHIFT(FIX(1.40200) * x + ONE_HALF, SCALEBITS);

+    /* Cb=>B value is nearest int to 1.77200 * x */

+    upsample->Cb_b_tab[i] = (int)

+		    RIGHT_SHIFT(FIX(1.77200) * x + ONE_HALF, SCALEBITS);

+    /* Cr=>G value is scaled-up -0.71414 * x */

+    upsample->Cr_g_tab[i] = (- FIX(0.71414)) * x;

+    /* Cb=>G value is scaled-up -0.34414 * x */

+    /* We also add in ONE_HALF so that need not do it in inner loop */

+    upsample->Cb_g_tab[i] = (- FIX(0.34414)) * x + ONE_HALF;

+  }

+}

+

+

+/*

+ * Initialize for an upsampling pass.

+ */

+

+METHODDEF void

+start_pass_merged_upsample (j_decompress_ptr cinfo)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+

+  /* Mark the spare buffer empty */

+  upsample->spare_full = FALSE;

+  /* Initialize total-height counter for detecting bottom of image */

+  upsample->rows_to_go = cinfo->output_height;

+}

+

+

+/*

+ * Control routine to do upsampling (and color conversion).

+ *

+ * The control routine just handles the row buffering considerations.

+ */

+

+METHODDEF void

+merged_2v_upsample (j_decompress_ptr cinfo,

+		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+		    JDIMENSION in_row_groups_avail,

+		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+		    JDIMENSION out_rows_avail)

+/* 2:1 vertical sampling case: may need a spare row. */

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  JSAMPROW work_ptrs[2];

+  JDIMENSION num_rows;		/* number of rows returned to caller */

+

+  if (upsample->spare_full) {

+    /* If we have a spare row saved from a previous cycle, just return it. */

+    jcopy_sample_rows(& upsample->spare_row, 0, output_buf + *out_row_ctr, 0,

+		      1, upsample->out_row_width);

+    num_rows = 1;

+    upsample->spare_full = FALSE;

+  } else {

+    /* Figure number of rows to return to caller. */

+    num_rows = 2;

+    /* Not more than the distance to the end of the image. */

+    if (num_rows > upsample->rows_to_go)

+      num_rows = upsample->rows_to_go;

+    /* And not more than what the client can accept: */

+    out_rows_avail -= *out_row_ctr;

+    if (num_rows > out_rows_avail)

+      num_rows = out_rows_avail;

+    /* Create output pointer array for upsampler. */

+    work_ptrs[0] = output_buf[*out_row_ctr];

+    if (num_rows > 1) {

+      work_ptrs[1] = output_buf[*out_row_ctr + 1];

+    } else {

+      work_ptrs[1] = upsample->spare_row;

+      upsample->spare_full = TRUE;

+    }

+    /* Now do the upsampling. */

+    (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr, work_ptrs);

+  }

+

+  /* Adjust counts */

+  *out_row_ctr += num_rows;

+  upsample->rows_to_go -= num_rows;

+  /* When the buffer is emptied, declare this input row group consumed */

+  if (! upsample->spare_full)

+    (*in_row_group_ctr)++;

+}

+

+

+METHODDEF void

+merged_1v_upsample (j_decompress_ptr cinfo,

+		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+		    JDIMENSION in_row_groups_avail,

+		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+		    JDIMENSION out_rows_avail)

+/* 1:1 vertical sampling case: much easier, never need a spare row. */

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+

+  /* Just do the upsampling. */

+  (*upsample->upmethod) (cinfo, input_buf, *in_row_group_ctr,

+			 output_buf + *out_row_ctr);

+  /* Adjust counts */

+  (*out_row_ctr)++;

+  (*in_row_group_ctr)++;

+}

+

+

+/*

+ * These are the routines invoked by the control routines to do

+ * the actual upsampling/conversion.  One row group is processed per call.

+ *

+ * Note: since we may be writing directly into application-supplied buffers,

+ * we have to be honest about the output width; we can't assume the buffer

+ * has been rounded up to an even width.

+ */

+

+

+/*

+ * Upsample and color convert for the case of 2:1 horizontal and 1:1 vertical.

+ */

+

+METHODDEF void

+h2v1_merged_upsample (j_decompress_ptr cinfo,

+		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,

+		      JSAMPARRAY output_buf)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  register int y, cred, cgreen, cblue;

+  int cb, cr;

+  register JSAMPROW outptr;

+  JSAMPROW inptr0, inptr1, inptr2;

+  JDIMENSION col;

+  /* copy these pointers into registers if possible */

+  register JSAMPLE * range_limit = cinfo->sample_range_limit;

+  int * Crrtab = upsample->Cr_r_tab;

+  int * Cbbtab = upsample->Cb_b_tab;

+  INT32 * Crgtab = upsample->Cr_g_tab;

+  INT32 * Cbgtab = upsample->Cb_g_tab;

+  SHIFT_TEMPS

+

+  inptr0 = input_buf[0][in_row_group_ctr];

+  inptr1 = input_buf[1][in_row_group_ctr];

+  inptr2 = input_buf[2][in_row_group_ctr];

+  outptr = output_buf[0];

+  /* Loop for each pair of output pixels */

+  for (col = cinfo->output_width >> 1; col > 0; col--) {

+    /* Do the chroma part of the calculation */

+    cb = GETJSAMPLE(*inptr1++);

+    cr = GETJSAMPLE(*inptr2++);

+    cred = Crrtab[cr];

+    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);

+    cblue = Cbbtab[cb];

+    /* Fetch 2 Y values and emit 2 pixels */

+    y  = GETJSAMPLE(*inptr0++);

+    outptr[RGB_RED] =   range_limit[y + cred];

+    outptr[RGB_GREEN] = range_limit[y + cgreen];

+    outptr[RGB_BLUE] =  range_limit[y + cblue];

+    outptr += RGB_PIXELSIZE;

+    y  = GETJSAMPLE(*inptr0++);

+    outptr[RGB_RED] =   range_limit[y + cred];

+    outptr[RGB_GREEN] = range_limit[y + cgreen];

+    outptr[RGB_BLUE] =  range_limit[y + cblue];

+    outptr += RGB_PIXELSIZE;

+  }

+  /* If image width is odd, do the last output column separately */

+  if (cinfo->output_width & 1) {

+    cb = GETJSAMPLE(*inptr1);

+    cr = GETJSAMPLE(*inptr2);

+    cred = Crrtab[cr];

+    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);

+    cblue = Cbbtab[cb];

+    y  = GETJSAMPLE(*inptr0);

+    outptr[RGB_RED] =   range_limit[y + cred];

+    outptr[RGB_GREEN] = range_limit[y + cgreen];

+    outptr[RGB_BLUE] =  range_limit[y + cblue];

+  }

+}

+

+

+/*

+ * Upsample and color convert for the case of 2:1 horizontal and 2:1 vertical.

+ */

+

+METHODDEF void

+h2v2_merged_upsample (j_decompress_ptr cinfo,

+		      JSAMPIMAGE input_buf, JDIMENSION in_row_group_ctr,

+		      JSAMPARRAY output_buf)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  register int y, cred, cgreen, cblue;

+  int cb, cr;

+  register JSAMPROW outptr0, outptr1;

+  JSAMPROW inptr00, inptr01, inptr1, inptr2;

+  JDIMENSION col;

+  /* copy these pointers into registers if possible */

+  register JSAMPLE * range_limit = cinfo->sample_range_limit;

+  int * Crrtab = upsample->Cr_r_tab;

+  int * Cbbtab = upsample->Cb_b_tab;

+  INT32 * Crgtab = upsample->Cr_g_tab;

+  INT32 * Cbgtab = upsample->Cb_g_tab;

+  SHIFT_TEMPS

+

+  inptr00 = input_buf[0][in_row_group_ctr*2];

+  inptr01 = input_buf[0][in_row_group_ctr*2 + 1];

+  inptr1 = input_buf[1][in_row_group_ctr];

+  inptr2 = input_buf[2][in_row_group_ctr];

+  outptr0 = output_buf[0];

+  outptr1 = output_buf[1];

+  /* Loop for each group of output pixels */

+  for (col = cinfo->output_width >> 1; col > 0; col--) {

+    /* Do the chroma part of the calculation */

+    cb = GETJSAMPLE(*inptr1++);

+    cr = GETJSAMPLE(*inptr2++);

+    cred = Crrtab[cr];

+    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);

+    cblue = Cbbtab[cb];

+    /* Fetch 4 Y values and emit 4 pixels */

+    y  = GETJSAMPLE(*inptr00++);

+    outptr0[RGB_RED] =   range_limit[y + cred];

+    outptr0[RGB_GREEN] = range_limit[y + cgreen];

+    outptr0[RGB_BLUE] =  range_limit[y + cblue];

+    outptr0 += RGB_PIXELSIZE;

+    y  = GETJSAMPLE(*inptr00++);

+    outptr0[RGB_RED] =   range_limit[y + cred];

+    outptr0[RGB_GREEN] = range_limit[y + cgreen];

+    outptr0[RGB_BLUE] =  range_limit[y + cblue];

+    outptr0 += RGB_PIXELSIZE;

+    y  = GETJSAMPLE(*inptr01++);

+    outptr1[RGB_RED] =   range_limit[y + cred];

+    outptr1[RGB_GREEN] = range_limit[y + cgreen];

+    outptr1[RGB_BLUE] =  range_limit[y + cblue];

+    outptr1 += RGB_PIXELSIZE;

+    y  = GETJSAMPLE(*inptr01++);

+    outptr1[RGB_RED] =   range_limit[y + cred];

+    outptr1[RGB_GREEN] = range_limit[y + cgreen];

+    outptr1[RGB_BLUE] =  range_limit[y + cblue];

+    outptr1 += RGB_PIXELSIZE;

+  }

+  /* If image width is odd, do the last output column separately */

+  if (cinfo->output_width & 1) {

+    cb = GETJSAMPLE(*inptr1);

+    cr = GETJSAMPLE(*inptr2);

+    cred = Crrtab[cr];

+    cgreen = (int) RIGHT_SHIFT(Cbgtab[cb] + Crgtab[cr], SCALEBITS);

+    cblue = Cbbtab[cb];

+    y  = GETJSAMPLE(*inptr00);

+    outptr0[RGB_RED] =   range_limit[y + cred];

+    outptr0[RGB_GREEN] = range_limit[y + cgreen];

+    outptr0[RGB_BLUE] =  range_limit[y + cblue];

+    y  = GETJSAMPLE(*inptr01);

+    outptr1[RGB_RED] =   range_limit[y + cred];

+    outptr1[RGB_GREEN] = range_limit[y + cgreen];

+    outptr1[RGB_BLUE] =  range_limit[y + cblue];

+  }

+}

+

+

+/*

+ * Module initialization routine for merged upsampling/color conversion.

+ *

+ * NB: this is called under the conditions determined by use_merged_upsample()

+ * in jdmaster.c.  That routine MUST correspond to the actual capabilities

+ * of this module; no safety checks are made here.

+ */

+

+GLOBAL void

+jinit_merged_upsampler (j_decompress_ptr cinfo)

+{

+  my_upsample_ptr upsample;

+

+  upsample = (my_upsample_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_upsampler));

+  cinfo->upsample = (struct jpeg_upsampler *) upsample;

+  upsample->pub.start_pass = start_pass_merged_upsample;

+  upsample->pub.need_context_rows = FALSE;

+

+  upsample->out_row_width = cinfo->output_width * cinfo->out_color_components;

+

+  if (cinfo->max_v_samp_factor == 2) {

+    upsample->pub.upsample = merged_2v_upsample;

+    upsample->upmethod = h2v2_merged_upsample;

+    /* Allocate a spare row buffer */

+    upsample->spare_row = (JSAMPROW)

+      (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+		(size_t) (upsample->out_row_width * SIZEOF(JSAMPLE)));

+  } else {

+    upsample->pub.upsample = merged_1v_upsample;

+    upsample->upmethod = h2v1_merged_upsample;

+    /* No spare row needed */

+    upsample->spare_row = NULL;

+  }

+

+  build_ycc_rgb_table(cinfo);

+}

+

+#endif /* UPSAMPLE_MERGING_SUPPORTED */

diff --git a/code/jpeg-6/jdphuff.c b/code/jpeg-6/jdphuff.c
new file mode 100755
index 0000000..9399bcc
--- /dev/null
+++ b/code/jpeg-6/jdphuff.c
@@ -0,0 +1,642 @@
+/*

+ * jdphuff.c

+ *

+ * Copyright (C) 1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains Huffman entropy decoding routines for progressive JPEG.

+ *

+ * Much of the complexity here has to do with supporting input suspension.

+ * If the data source module demands suspension, we want to be able to back

+ * up to the start of the current MCU.  To do this, we copy state variables

+ * into local working storage, and update them back to the permanent

+ * storage only upon successful completion of an MCU.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdhuff.h"		/* Declarations shared with jdhuff.c */

+

+

+#ifdef D_PROGRESSIVE_SUPPORTED

+

+/*

+ * Expanded entropy decoder object for progressive Huffman decoding.

+ *

+ * The savable_state subrecord contains fields that change within an MCU,

+ * but must not be updated permanently until we complete the MCU.

+ */

+

+typedef struct {

+  unsigned int EOBRUN;			/* remaining EOBs in EOBRUN */

+  int last_dc_val[MAX_COMPS_IN_SCAN];	/* last DC coef for each component */

+} savable_state;

+

+/* This macro is to work around compilers with missing or broken

+ * structure assignment.  You'll need to fix this code if you have

+ * such a compiler and you change MAX_COMPS_IN_SCAN.

+ */

+

+#ifndef NO_STRUCT_ASSIGN

+#define ASSIGN_STATE(dest,src)  ((dest) = (src))

+#else

+#if MAX_COMPS_IN_SCAN == 4

+#define ASSIGN_STATE(dest,src)  \

+	((dest).EOBRUN = (src).EOBRUN, \

+	 (dest).last_dc_val[0] = (src).last_dc_val[0], \

+	 (dest).last_dc_val[1] = (src).last_dc_val[1], \

+	 (dest).last_dc_val[2] = (src).last_dc_val[2], \

+	 (dest).last_dc_val[3] = (src).last_dc_val[3])

+#endif

+#endif

+

+

+typedef struct {

+  struct jpeg_entropy_decoder pub; /* public fields */

+

+  /* These fields are loaded into local variables at start of each MCU.

+   * In case of suspension, we exit WITHOUT updating them.

+   */

+  bitread_perm_state bitstate;	/* Bit buffer at start of MCU */

+  savable_state saved;		/* Other state at start of MCU */

+

+  /* These fields are NOT loaded into local working state. */

+  unsigned int restarts_to_go;	/* MCUs left in this restart interval */

+

+  /* Pointers to derived tables (these workspaces have image lifespan) */

+  d_derived_tbl * derived_tbls[NUM_HUFF_TBLS];

+

+  d_derived_tbl * ac_derived_tbl; /* active table during an AC scan */

+} phuff_entropy_decoder;

+

+typedef phuff_entropy_decoder * phuff_entropy_ptr;

+

+/* Forward declarations */

+METHODDEF boolean decode_mcu_DC_first JPP((j_decompress_ptr cinfo,

+					   JBLOCKROW *MCU_data));

+METHODDEF boolean decode_mcu_AC_first JPP((j_decompress_ptr cinfo,

+					   JBLOCKROW *MCU_data));

+METHODDEF boolean decode_mcu_DC_refine JPP((j_decompress_ptr cinfo,

+					    JBLOCKROW *MCU_data));

+METHODDEF boolean decode_mcu_AC_refine JPP((j_decompress_ptr cinfo,

+					    JBLOCKROW *MCU_data));

+

+

+/*

+ * Initialize for a Huffman-compressed scan.

+ */

+

+METHODDEF void

+start_pass_phuff_decoder (j_decompress_ptr cinfo)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  boolean is_DC_band, bad;

+  int ci, coefi, tbl;

+  int *coef_bit_ptr;

+  jpeg_component_info * compptr;

+

+  is_DC_band = (cinfo->Ss == 0);

+

+  /* Validate scan parameters */

+  bad = FALSE;

+  if (is_DC_band) {

+    if (cinfo->Se != 0)

+      bad = TRUE;

+  } else {

+    /* need not check Ss/Se < 0 since they came from unsigned bytes */

+    if (cinfo->Ss > cinfo->Se || cinfo->Se >= DCTSIZE2)

+      bad = TRUE;

+    /* AC scans may have only one component */

+    if (cinfo->comps_in_scan != 1)

+      bad = TRUE;

+  }

+  if (cinfo->Ah != 0) {

+    /* Successive approximation refinement scan: must have Al = Ah-1. */

+    if (cinfo->Al != cinfo->Ah-1)

+      bad = TRUE;

+  }

+  if (cinfo->Al > 13)		/* need not check for < 0 */

+    bad = TRUE;

+  if (bad)

+    ERREXIT4(cinfo, JERR_BAD_PROGRESSION,

+	     cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al);

+  /* Update progression status, and verify that scan order is legal.

+   * Note that inter-scan inconsistencies are treated as warnings

+   * not fatal errors ... not clear if this is right way to behave.

+   */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    int cindex = cinfo->cur_comp_info[ci]->component_index;

+    coef_bit_ptr = & cinfo->coef_bits[cindex][0];

+    if (!is_DC_band && coef_bit_ptr[0] < 0) /* AC without prior DC scan */

+      WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0);

+    for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) {

+      int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi];

+      if (cinfo->Ah != expected)

+	WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi);

+      coef_bit_ptr[coefi] = cinfo->Al;

+    }

+  }

+

+  /* Select MCU decoding routine */

+  if (cinfo->Ah == 0) {

+    if (is_DC_band)

+      entropy->pub.decode_mcu = decode_mcu_DC_first;

+    else

+      entropy->pub.decode_mcu = decode_mcu_AC_first;

+  } else {

+    if (is_DC_band)

+      entropy->pub.decode_mcu = decode_mcu_DC_refine;

+    else

+      entropy->pub.decode_mcu = decode_mcu_AC_refine;

+  }

+

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {

+    compptr = cinfo->cur_comp_info[ci];

+    /* Make sure requested tables are present, and compute derived tables.

+     * We may build same derived table more than once, but it's not expensive.

+     */

+    if (is_DC_band) {

+      if (cinfo->Ah == 0) {	/* DC refinement needs no table */

+	tbl = compptr->dc_tbl_no;

+	if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||

+	    cinfo->dc_huff_tbl_ptrs[tbl] == NULL)

+	  ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);

+	jpeg_make_d_derived_tbl(cinfo, cinfo->dc_huff_tbl_ptrs[tbl],

+				& entropy->derived_tbls[tbl]);

+      }

+    } else {

+      tbl = compptr->ac_tbl_no;

+      if (tbl < 0 || tbl >= NUM_HUFF_TBLS ||

+          cinfo->ac_huff_tbl_ptrs[tbl] == NULL)

+        ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tbl);

+      jpeg_make_d_derived_tbl(cinfo, cinfo->ac_huff_tbl_ptrs[tbl],

+			      & entropy->derived_tbls[tbl]);

+      /* remember the single active table */

+      entropy->ac_derived_tbl = entropy->derived_tbls[tbl];

+    }

+    /* Initialize DC predictions to 0 */

+    entropy->saved.last_dc_val[ci] = 0;

+  }

+

+  /* Initialize bitread state variables */

+  entropy->bitstate.bits_left = 0;

+  entropy->bitstate.get_buffer = 0; /* unnecessary, but keeps Purify quiet */

+  entropy->bitstate.printed_eod = FALSE;

+

+  /* Initialize private state variables */

+  entropy->saved.EOBRUN = 0;

+

+  /* Initialize restart counter */

+  entropy->restarts_to_go = cinfo->restart_interval;

+}

+

+

+/*

+ * Figure F.12: extend sign bit.

+ * On some machines, a shift and add will be faster than a table lookup.

+ */

+

+#ifdef AVOID_TABLES

+

+#define HUFF_EXTEND(x,s)  ((x) < (1<<((s)-1)) ? (x) + (((-1)<<(s)) + 1) : (x))

+

+#else

+

+#define HUFF_EXTEND(x,s)  ((x) < extend_test[s] ? (x) + extend_offset[s] : (x))

+

+static const int extend_test[16] =   /* entry n is 2**(n-1) */

+  { 0, 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,

+    0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000 };

+

+static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */

+  { 0, ((-1)<<1) + 1, ((-1)<<2) + 1, ((-1)<<3) + 1, ((-1)<<4) + 1,

+    ((-1)<<5) + 1, ((-1)<<6) + 1, ((-1)<<7) + 1, ((-1)<<8) + 1,

+    ((-1)<<9) + 1, ((-1)<<10) + 1, ((-1)<<11) + 1, ((-1)<<12) + 1,

+    ((-1)<<13) + 1, ((-1)<<14) + 1, ((-1)<<15) + 1 };

+

+#endif /* AVOID_TABLES */

+

+

+/*

+ * Check for a restart marker & resynchronize decoder.

+ * Returns FALSE if must suspend.

+ */

+

+LOCAL boolean

+process_restart (j_decompress_ptr cinfo)

+{

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  int ci;

+

+  /* Throw away any unused bits remaining in bit buffer; */

+  /* include any full bytes in next_marker's count of discarded bytes */

+  cinfo->marker->discarded_bytes += entropy->bitstate.bits_left / 8;

+  entropy->bitstate.bits_left = 0;

+

+  /* Advance past the RSTn marker */

+  if (! (*cinfo->marker->read_restart_marker) (cinfo))

+    return FALSE;

+

+  /* Re-initialize DC predictions to 0 */

+  for (ci = 0; ci < cinfo->comps_in_scan; ci++)

+    entropy->saved.last_dc_val[ci] = 0;

+  /* Re-init EOB run count, too */

+  entropy->saved.EOBRUN = 0;

+

+  /* Reset restart counter */

+  entropy->restarts_to_go = cinfo->restart_interval;

+

+  /* Next segment can get another out-of-data warning */

+  entropy->bitstate.printed_eod = FALSE;

+

+  return TRUE;

+}

+

+

+/*

+ * Huffman MCU decoding.

+ * Each of these routines decodes and returns one MCU's worth of

+ * Huffman-compressed coefficients. 

+ * The coefficients are reordered from zigzag order into natural array order,

+ * but are not dequantized.

+ *

+ * The i'th block of the MCU is stored into the block pointed to by

+ * MCU_data[i].  WE ASSUME THIS AREA IS INITIALLY ZEROED BY THE CALLER.

+ *

+ * We return FALSE if data source requested suspension.  In that case no

+ * changes have been made to permanent state.  (Exception: some output

+ * coefficients may already have been assigned.  This is harmless for

+ * spectral selection, since we'll just re-assign them on the next call.

+ * Successive approximation AC refinement has to be more careful, however.)

+ */

+

+/*

+ * MCU decoding for DC initial scan (either spectral selection,

+ * or first pass of successive approximation).

+ */

+

+METHODDEF boolean

+decode_mcu_DC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)

+{   

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  int Al = cinfo->Al;

+  register int s, r;

+  int blkn, ci;

+  JBLOCKROW block;

+  BITREAD_STATE_VARS;

+  savable_state state;

+  d_derived_tbl * tbl;

+  jpeg_component_info * compptr;

+

+  /* Process restart marker if needed; may have to suspend */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! process_restart(cinfo))

+	return FALSE;

+  }

+

+  /* Load up working state */

+  BITREAD_LOAD_STATE(cinfo,entropy->bitstate);

+  ASSIGN_STATE(state, entropy->saved);

+

+  /* Outer loop handles each block in the MCU */

+

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    block = MCU_data[blkn];

+    ci = cinfo->MCU_membership[blkn];

+    compptr = cinfo->cur_comp_info[ci];

+    tbl = entropy->derived_tbls[compptr->dc_tbl_no];

+

+    /* Decode a single block's worth of coefficients */

+

+    /* Section F.2.2.1: decode the DC coefficient difference */

+    HUFF_DECODE(s, br_state, tbl, return FALSE, label1);

+    if (s) {

+      CHECK_BIT_BUFFER(br_state, s, return FALSE);

+      r = GET_BITS(s);

+      s = HUFF_EXTEND(r, s);

+    }

+

+    /* Convert DC difference to actual value, update last_dc_val */

+    s += state.last_dc_val[ci];

+    state.last_dc_val[ci] = s;

+    /* Scale and output the DC coefficient (assumes jpeg_natural_order[0]=0) */

+    (*block)[0] = (JCOEF) (s << Al);

+  }

+

+  /* Completed MCU, so update state */

+  BITREAD_SAVE_STATE(cinfo,entropy->bitstate);

+  ASSIGN_STATE(entropy->saved, state);

+

+  /* Account for restart interval (no-op if not using restarts) */

+  entropy->restarts_to_go--;

+

+  return TRUE;

+}

+

+

+/*

+ * MCU decoding for AC initial scan (either spectral selection,

+ * or first pass of successive approximation).

+ */

+

+METHODDEF boolean

+decode_mcu_AC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)

+{   

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  int Se = cinfo->Se;

+  int Al = cinfo->Al;

+  register int s, k, r;

+  unsigned int EOBRUN;

+  JBLOCKROW block;

+  BITREAD_STATE_VARS;

+  d_derived_tbl * tbl;

+

+  /* Process restart marker if needed; may have to suspend */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! process_restart(cinfo))

+	return FALSE;

+  }

+

+  /* Load up working state.

+   * We can avoid loading/saving bitread state if in an EOB run.

+   */

+  EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we care about */

+

+  /* There is always only one block per MCU */

+

+  if (EOBRUN > 0)		/* if it's a band of zeroes... */

+    EOBRUN--;			/* ...process it now (we do nothing) */

+  else {

+    BITREAD_LOAD_STATE(cinfo,entropy->bitstate);

+    block = MCU_data[0];

+    tbl = entropy->ac_derived_tbl;

+

+    for (k = cinfo->Ss; k <= Se; k++) {

+      HUFF_DECODE(s, br_state, tbl, return FALSE, label2);

+      r = s >> 4;

+      s &= 15;

+      if (s) {

+        k += r;

+        CHECK_BIT_BUFFER(br_state, s, return FALSE);

+        r = GET_BITS(s);

+        s = HUFF_EXTEND(r, s);

+	/* Scale and output coefficient in natural (dezigzagged) order */

+        (*block)[jpeg_natural_order[k]] = (JCOEF) (s << Al);

+      } else {

+        if (r == 15) {		/* ZRL */

+          k += 15;		/* skip 15 zeroes in band */

+        } else {		/* EOBr, run length is 2^r + appended bits */

+          EOBRUN = 1 << r;

+          if (r) {		/* EOBr, r > 0 */

+	    CHECK_BIT_BUFFER(br_state, r, return FALSE);

+            r = GET_BITS(r);

+            EOBRUN += r;

+          }

+	  EOBRUN--;		/* this band is processed at this moment */

+	  break;		/* force end-of-band */

+	}

+      }

+    }

+

+    BITREAD_SAVE_STATE(cinfo,entropy->bitstate);

+  }

+

+  /* Completed MCU, so update state */

+  entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we care about */

+

+  /* Account for restart interval (no-op if not using restarts) */

+  entropy->restarts_to_go--;

+

+  return TRUE;

+}

+

+

+/*

+ * MCU decoding for DC successive approximation refinement scan.

+ * Note: we assume such scans can be multi-component, although the spec

+ * is not very clear on the point.

+ */

+

+METHODDEF boolean

+decode_mcu_DC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)

+{   

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  int p1 = 1 << cinfo->Al;	/* 1 in the bit position being coded */

+  int blkn;

+  JBLOCKROW block;

+  BITREAD_STATE_VARS;

+

+  /* Process restart marker if needed; may have to suspend */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! process_restart(cinfo))

+	return FALSE;

+  }

+

+  /* Load up working state */

+  BITREAD_LOAD_STATE(cinfo,entropy->bitstate);

+

+  /* Outer loop handles each block in the MCU */

+

+  for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) {

+    block = MCU_data[blkn];

+

+    /* Encoded data is simply the next bit of the two's-complement DC value */

+    CHECK_BIT_BUFFER(br_state, 1, return FALSE);

+    if (GET_BITS(1))

+      (*block)[0] |= p1;

+    /* Note: since we use |=, repeating the assignment later is safe */

+  }

+

+  /* Completed MCU, so update state */

+  BITREAD_SAVE_STATE(cinfo,entropy->bitstate);

+

+  /* Account for restart interval (no-op if not using restarts) */

+  entropy->restarts_to_go--;

+

+  return TRUE;

+}

+

+

+/*

+ * MCU decoding for AC successive approximation refinement scan.

+ */

+

+METHODDEF boolean

+decode_mcu_AC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)

+{   

+  phuff_entropy_ptr entropy = (phuff_entropy_ptr) cinfo->entropy;

+  int Se = cinfo->Se;

+  int p1 = 1 << cinfo->Al;	/* 1 in the bit position being coded */

+  int m1 = (-1) << cinfo->Al;	/* -1 in the bit position being coded */

+  register int s, k, r;

+  unsigned int EOBRUN;

+  JBLOCKROW block;

+  JCOEFPTR thiscoef;

+  BITREAD_STATE_VARS;

+  d_derived_tbl * tbl;

+  int num_newnz;

+  int newnz_pos[DCTSIZE2];

+

+  /* Process restart marker if needed; may have to suspend */

+  if (cinfo->restart_interval) {

+    if (entropy->restarts_to_go == 0)

+      if (! process_restart(cinfo))

+	return FALSE;

+  }

+

+  /* Load up working state */

+  BITREAD_LOAD_STATE(cinfo,entropy->bitstate);

+  EOBRUN = entropy->saved.EOBRUN; /* only part of saved state we care about */

+

+  /* There is always only one block per MCU */

+  block = MCU_data[0];

+  tbl = entropy->ac_derived_tbl;

+

+  /* If we are forced to suspend, we must undo the assignments to any newly

+   * nonzero coefficients in the block, because otherwise we'd get confused

+   * next time about which coefficients were already nonzero.

+   * But we need not undo addition of bits to already-nonzero coefficients;

+   * instead, we can test the current bit position to see if we already did it.

+   */

+  num_newnz = 0;

+

+  /* initialize coefficient loop counter to start of band */

+  k = cinfo->Ss;

+

+  if (EOBRUN == 0) {

+    for (; k <= Se; k++) {

+      HUFF_DECODE(s, br_state, tbl, goto undoit, label3);

+      r = s >> 4;

+      s &= 15;

+      if (s) {

+	if (s != 1)		/* size of new coef should always be 1 */

+	  WARNMS(cinfo, JWRN_HUFF_BAD_CODE);

+        CHECK_BIT_BUFFER(br_state, 1, goto undoit);

+        if (GET_BITS(1))

+	  s = p1;		/* newly nonzero coef is positive */

+	else

+	  s = m1;		/* newly nonzero coef is negative */

+      } else {

+	if (r != 15) {

+	  EOBRUN = 1 << r;	/* EOBr, run length is 2^r + appended bits */

+	  if (r) {

+	    CHECK_BIT_BUFFER(br_state, r, goto undoit);

+	    r = GET_BITS(r);

+	    EOBRUN += r;

+	  }

+	  break;		/* rest of block is handled by EOB logic */

+	}

+	/* note s = 0 for processing ZRL */

+      }

+      /* Advance over already-nonzero coefs and r still-zero coefs,

+       * appending correction bits to the nonzeroes.  A correction bit is 1

+       * if the absolute value of the coefficient must be increased.

+       */

+      do {

+	thiscoef = *block + jpeg_natural_order[k];

+	if (*thiscoef != 0) {

+	  CHECK_BIT_BUFFER(br_state, 1, goto undoit);

+	  if (GET_BITS(1)) {

+	    if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */

+	      if (*thiscoef >= 0)

+		*thiscoef += p1;

+	      else

+		*thiscoef += m1;

+	    }

+	  }

+	} else {

+	  if (--r < 0)

+	    break;		/* reached target zero coefficient */

+	}

+	k++;

+      } while (k <= Se);

+      if (s) {

+	int pos = jpeg_natural_order[k];

+	/* Output newly nonzero coefficient */

+	(*block)[pos] = (JCOEF) s;

+	/* Remember its position in case we have to suspend */

+	newnz_pos[num_newnz++] = pos;

+      }

+    }

+  }

+

+  if (EOBRUN > 0) {

+    /* Scan any remaining coefficient positions after the end-of-band

+     * (the last newly nonzero coefficient, if any).  Append a correction

+     * bit to each already-nonzero coefficient.  A correction bit is 1

+     * if the absolute value of the coefficient must be increased.

+     */

+    for (; k <= Se; k++) {

+      thiscoef = *block + jpeg_natural_order[k];

+      if (*thiscoef != 0) {

+	CHECK_BIT_BUFFER(br_state, 1, goto undoit);

+	if (GET_BITS(1)) {

+	  if ((*thiscoef & p1) == 0) { /* do nothing if already changed it */

+	    if (*thiscoef >= 0)

+	      *thiscoef += p1;

+	    else

+	      *thiscoef += m1;

+	  }

+	}

+      }

+    }

+    /* Count one block completed in EOB run */

+    EOBRUN--;

+  }

+

+  /* Completed MCU, so update state */

+  BITREAD_SAVE_STATE(cinfo,entropy->bitstate);

+  entropy->saved.EOBRUN = EOBRUN; /* only part of saved state we care about */

+

+  /* Account for restart interval (no-op if not using restarts) */

+  entropy->restarts_to_go--;

+

+  return TRUE;

+

+undoit:

+  /* Re-zero any output coefficients that we made newly nonzero */

+  while (num_newnz > 0)

+    (*block)[newnz_pos[--num_newnz]] = 0;

+

+  return FALSE;

+}

+

+

+/*

+ * Module initialization routine for progressive Huffman entropy decoding.

+ */

+

+GLOBAL void

+jinit_phuff_decoder (j_decompress_ptr cinfo)

+{

+  phuff_entropy_ptr entropy;

+  int *coef_bit_ptr;

+  int ci, i;

+

+  entropy = (phuff_entropy_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(phuff_entropy_decoder));

+  cinfo->entropy = (struct jpeg_entropy_decoder *) entropy;

+  entropy->pub.start_pass = start_pass_phuff_decoder;

+

+  /* Mark derived tables unallocated */

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    entropy->derived_tbls[i] = NULL;

+  }

+

+  /* Create progression status table */

+  cinfo->coef_bits = (int (*)[DCTSIZE2])

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				cinfo->num_components*DCTSIZE2*SIZEOF(int));

+  coef_bit_ptr = & cinfo->coef_bits[0][0];

+  for (ci = 0; ci < cinfo->num_components; ci++) 

+    for (i = 0; i < DCTSIZE2; i++)

+      *coef_bit_ptr++ = -1;

+}

+

+#endif /* D_PROGRESSIVE_SUPPORTED */

diff --git a/code/jpeg-6/jdpostct.c b/code/jpeg-6/jdpostct.c
new file mode 100755
index 0000000..e3283b0
--- /dev/null
+++ b/code/jpeg-6/jdpostct.c
@@ -0,0 +1,290 @@
+/*

+ * jdpostct.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the decompression postprocessing controller.

+ * This controller manages the upsampling, color conversion, and color

+ * quantization/reduction steps; specifically, it controls the buffering

+ * between upsample/color conversion and color quantization/reduction.

+ *

+ * If no color quantization/reduction is required, then this module has no

+ * work to do, and it just hands off to the upsample/color conversion code.

+ * An integrated upsample/convert/quantize process would replace this module

+ * entirely.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Private buffer controller object */

+

+typedef struct {

+  struct jpeg_d_post_controller pub; /* public fields */

+

+  /* Color quantization source buffer: this holds output data from

+   * the upsample/color conversion step to be passed to the quantizer.

+   * For two-pass color quantization, we need a full-image buffer;

+   * for one-pass operation, a strip buffer is sufficient.

+   */

+  jvirt_sarray_ptr whole_image;	/* virtual array, or NULL if one-pass */

+  JSAMPARRAY buffer;		/* strip buffer, or current strip of virtual */

+  JDIMENSION strip_height;	/* buffer size in rows */

+  /* for two-pass mode only: */

+  JDIMENSION starting_row;	/* row # of first row in current strip */

+  JDIMENSION next_row;		/* index of next row to fill/empty in strip */

+} my_post_controller;

+

+typedef my_post_controller * my_post_ptr;

+

+

+/* Forward declarations */

+METHODDEF void post_process_1pass

+	JPP((j_decompress_ptr cinfo,

+	     JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+	     JDIMENSION in_row_groups_avail,

+	     JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+	     JDIMENSION out_rows_avail));

+#ifdef QUANT_2PASS_SUPPORTED

+METHODDEF void post_process_prepass

+	JPP((j_decompress_ptr cinfo,

+	     JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+	     JDIMENSION in_row_groups_avail,

+	     JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+	     JDIMENSION out_rows_avail));

+METHODDEF void post_process_2pass

+	JPP((j_decompress_ptr cinfo,

+	     JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+	     JDIMENSION in_row_groups_avail,

+	     JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+	     JDIMENSION out_rows_avail));

+#endif

+

+

+/*

+ * Initialize for a processing pass.

+ */

+

+METHODDEF void

+start_pass_dpost (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)

+{

+  my_post_ptr post = (my_post_ptr) cinfo->post;

+

+  switch (pass_mode) {

+  case JBUF_PASS_THRU:

+    if (cinfo->quantize_colors) {

+      /* Single-pass processing with color quantization. */

+      post->pub.post_process_data = post_process_1pass;

+      /* We could be doing buffered-image output before starting a 2-pass

+       * color quantization; in that case, jinit_d_post_controller did not

+       * allocate a strip buffer.  Use the virtual-array buffer as workspace.

+       */

+      if (post->buffer == NULL) {

+	post->buffer = (*cinfo->mem->access_virt_sarray)

+	  ((j_common_ptr) cinfo, post->whole_image,

+	   (JDIMENSION) 0, post->strip_height, TRUE);

+      }

+    } else {

+      /* For single-pass processing without color quantization,

+       * I have no work to do; just call the upsampler directly.

+       */

+      post->pub.post_process_data = cinfo->upsample->upsample;

+    }

+    break;

+#ifdef QUANT_2PASS_SUPPORTED

+  case JBUF_SAVE_AND_PASS:

+    /* First pass of 2-pass quantization */

+    if (post->whole_image == NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    post->pub.post_process_data = post_process_prepass;

+    break;

+  case JBUF_CRANK_DEST:

+    /* Second pass of 2-pass quantization */

+    if (post->whole_image == NULL)

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    post->pub.post_process_data = post_process_2pass;

+    break;

+#endif /* QUANT_2PASS_SUPPORTED */

+  default:

+    ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+    break;

+  }

+  post->starting_row = post->next_row = 0;

+}

+

+

+/*

+ * Process some data in the one-pass (strip buffer) case.

+ * This is used for color precision reduction as well as one-pass quantization.

+ */

+

+METHODDEF void

+post_process_1pass (j_decompress_ptr cinfo,

+		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+		    JDIMENSION in_row_groups_avail,

+		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+		    JDIMENSION out_rows_avail)

+{

+  my_post_ptr post = (my_post_ptr) cinfo->post;

+  JDIMENSION num_rows, max_rows;

+

+  /* Fill the buffer, but not more than what we can dump out in one go. */

+  /* Note we rely on the upsampler to detect bottom of image. */

+  max_rows = out_rows_avail - *out_row_ctr;

+  if (max_rows > post->strip_height)

+    max_rows = post->strip_height;

+  num_rows = 0;

+  (*cinfo->upsample->upsample) (cinfo,

+		input_buf, in_row_group_ctr, in_row_groups_avail,

+		post->buffer, &num_rows, max_rows);

+  /* Quantize and emit data. */

+  (*cinfo->cquantize->color_quantize) (cinfo,

+		post->buffer, output_buf + *out_row_ctr, (int) num_rows);

+  *out_row_ctr += num_rows;

+}

+

+

+#ifdef QUANT_2PASS_SUPPORTED

+

+/*

+ * Process some data in the first pass of 2-pass quantization.

+ */

+

+METHODDEF void

+post_process_prepass (j_decompress_ptr cinfo,

+		      JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+		      JDIMENSION in_row_groups_avail,

+		      JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+		      JDIMENSION out_rows_avail)

+{

+  my_post_ptr post = (my_post_ptr) cinfo->post;

+  JDIMENSION old_next_row, num_rows;

+

+  /* Reposition virtual buffer if at start of strip. */

+  if (post->next_row == 0) {

+    post->buffer = (*cinfo->mem->access_virt_sarray)

+	((j_common_ptr) cinfo, post->whole_image,

+	 post->starting_row, post->strip_height, TRUE);

+  }

+

+  /* Upsample some data (up to a strip height's worth). */

+  old_next_row = post->next_row;

+  (*cinfo->upsample->upsample) (cinfo,

+		input_buf, in_row_group_ctr, in_row_groups_avail,

+		post->buffer, &post->next_row, post->strip_height);

+

+  /* Allow quantizer to scan new data.  No data is emitted, */

+  /* but we advance out_row_ctr so outer loop can tell when we're done. */

+  if (post->next_row > old_next_row) {

+    num_rows = post->next_row - old_next_row;

+    (*cinfo->cquantize->color_quantize) (cinfo, post->buffer + old_next_row,

+					 (JSAMPARRAY) NULL, (int) num_rows);

+    *out_row_ctr += num_rows;

+  }

+

+  /* Advance if we filled the strip. */

+  if (post->next_row >= post->strip_height) {

+    post->starting_row += post->strip_height;

+    post->next_row = 0;

+  }

+}

+

+

+/*

+ * Process some data in the second pass of 2-pass quantization.

+ */

+

+METHODDEF void

+post_process_2pass (j_decompress_ptr cinfo,

+		    JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+		    JDIMENSION in_row_groups_avail,

+		    JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+		    JDIMENSION out_rows_avail)

+{

+  my_post_ptr post = (my_post_ptr) cinfo->post;

+  JDIMENSION num_rows, max_rows;

+

+  /* Reposition virtual buffer if at start of strip. */

+  if (post->next_row == 0) {

+    post->buffer = (*cinfo->mem->access_virt_sarray)

+	((j_common_ptr) cinfo, post->whole_image,

+	 post->starting_row, post->strip_height, FALSE);

+  }

+

+  /* Determine number of rows to emit. */

+  num_rows = post->strip_height - post->next_row; /* available in strip */

+  max_rows = out_rows_avail - *out_row_ctr; /* available in output area */

+  if (num_rows > max_rows)

+    num_rows = max_rows;

+  /* We have to check bottom of image here, can't depend on upsampler. */

+  max_rows = cinfo->output_height - post->starting_row;

+  if (num_rows > max_rows)

+    num_rows = max_rows;

+

+  /* Quantize and emit data. */

+  (*cinfo->cquantize->color_quantize) (cinfo,

+		post->buffer + post->next_row, output_buf + *out_row_ctr,

+		(int) num_rows);

+  *out_row_ctr += num_rows;

+

+  /* Advance if we filled the strip. */

+  post->next_row += num_rows;

+  if (post->next_row >= post->strip_height) {

+    post->starting_row += post->strip_height;

+    post->next_row = 0;

+  }

+}

+

+#endif /* QUANT_2PASS_SUPPORTED */

+

+

+/*

+ * Initialize postprocessing controller.

+ */

+

+GLOBAL void

+jinit_d_post_controller (j_decompress_ptr cinfo, boolean need_full_buffer)

+{

+  my_post_ptr post;

+

+  post = (my_post_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_post_controller));

+  cinfo->post = (struct jpeg_d_post_controller *) post;

+  post->pub.start_pass = start_pass_dpost;

+  post->whole_image = NULL;	/* flag for no virtual arrays */

+  post->buffer = NULL;		/* flag for no strip buffer */

+

+  /* Create the quantization buffer, if needed */

+  if (cinfo->quantize_colors) {

+    /* The buffer strip height is max_v_samp_factor, which is typically

+     * an efficient number of rows for upsampling to return.

+     * (In the presence of output rescaling, we might want to be smarter?)

+     */

+    post->strip_height = (JDIMENSION) cinfo->max_v_samp_factor;

+    if (need_full_buffer) {

+      /* Two-pass color quantization: need full-image storage. */

+      /* We round up the number of rows to a multiple of the strip height. */

+#ifdef QUANT_2PASS_SUPPORTED

+      post->whole_image = (*cinfo->mem->request_virt_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,

+	 cinfo->output_width * cinfo->out_color_components,

+	 (JDIMENSION) jround_up((long) cinfo->output_height,

+				(long) post->strip_height),

+	 post->strip_height);

+#else

+      ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);

+#endif /* QUANT_2PASS_SUPPORTED */

+    } else {

+      /* One-pass color quantization: just make a strip buffer. */

+      post->buffer = (*cinfo->mem->alloc_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE,

+	 cinfo->output_width * cinfo->out_color_components,

+	 post->strip_height);

+    }

+  }

+}

diff --git a/code/jpeg-6/jdsample.c b/code/jpeg-6/jdsample.c
new file mode 100755
index 0000000..bc171f4
--- /dev/null
+++ b/code/jpeg-6/jdsample.c
@@ -0,0 +1,478 @@
+/*

+ * jdsample.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains upsampling routines.

+ *

+ * Upsampling input data is counted in "row groups".  A row group

+ * is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size)

+ * sample rows of each component.  Upsampling will normally produce

+ * max_v_samp_factor pixel rows from each row group (but this could vary

+ * if the upsampler is applying a scale factor of its own).

+ *

+ * An excellent reference for image resampling is

+ *   Digital Image Warping, George Wolberg, 1990.

+ *   Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Pointer to routine to upsample a single component */

+typedef JMETHOD(void, upsample1_ptr,

+		(j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		 JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr));

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_upsampler pub;	/* public fields */

+

+  /* Color conversion buffer.  When using separate upsampling and color

+   * conversion steps, this buffer holds one upsampled row group until it

+   * has been color converted and output.

+   * Note: we do not allocate any storage for component(s) which are full-size,

+   * ie do not need rescaling.  The corresponding entry of color_buf[] is

+   * simply set to point to the input data array, thereby avoiding copying.

+   */

+  JSAMPARRAY color_buf[MAX_COMPONENTS];

+

+  /* Per-component upsampling method pointers */

+  upsample1_ptr methods[MAX_COMPONENTS];

+

+  int next_row_out;		/* counts rows emitted from color_buf */

+  JDIMENSION rows_to_go;	/* counts rows remaining in image */

+

+  /* Height of an input row group for each component. */

+  int rowgroup_height[MAX_COMPONENTS];

+

+  /* These arrays save pixel expansion factors so that int_expand need not

+   * recompute them each time.  They are unused for other upsampling methods.

+   */

+  UINT8 h_expand[MAX_COMPONENTS];

+  UINT8 v_expand[MAX_COMPONENTS];

+} my_upsampler;

+

+typedef my_upsampler * my_upsample_ptr;

+

+

+/*

+ * Initialize for an upsampling pass.

+ */

+

+METHODDEF void

+start_pass_upsample (j_decompress_ptr cinfo)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+

+  /* Mark the conversion buffer empty */

+  upsample->next_row_out = cinfo->max_v_samp_factor;

+  /* Initialize total-height counter for detecting bottom of image */

+  upsample->rows_to_go = cinfo->output_height;

+}

+

+

+/*

+ * Control routine to do upsampling (and color conversion).

+ *

+ * In this version we upsample each component independently.

+ * We upsample one row group into the conversion buffer, then apply

+ * color conversion a row at a time.

+ */

+

+METHODDEF void

+sep_upsample (j_decompress_ptr cinfo,

+	      JSAMPIMAGE input_buf, JDIMENSION *in_row_group_ctr,

+	      JDIMENSION in_row_groups_avail,

+	      JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+	      JDIMENSION out_rows_avail)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  int ci;

+  jpeg_component_info * compptr;

+  JDIMENSION num_rows;

+

+  /* Fill the conversion buffer, if it's empty */

+  if (upsample->next_row_out >= cinfo->max_v_samp_factor) {

+    for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+	 ci++, compptr++) {

+      /* Invoke per-component upsample method.  Notice we pass a POINTER

+       * to color_buf[ci], so that fullsize_upsample can change it.

+       */

+      (*upsample->methods[ci]) (cinfo, compptr,

+	input_buf[ci] + (*in_row_group_ctr * upsample->rowgroup_height[ci]),

+	upsample->color_buf + ci);

+    }

+    upsample->next_row_out = 0;

+  }

+

+  /* Color-convert and emit rows */

+

+  /* How many we have in the buffer: */

+  num_rows = (JDIMENSION) (cinfo->max_v_samp_factor - upsample->next_row_out);

+  /* Not more than the distance to the end of the image.  Need this test

+   * in case the image height is not a multiple of max_v_samp_factor:

+   */

+  if (num_rows > upsample->rows_to_go) 

+    num_rows = upsample->rows_to_go;

+  /* And not more than what the client can accept: */

+  out_rows_avail -= *out_row_ctr;

+  if (num_rows > out_rows_avail)

+    num_rows = out_rows_avail;

+

+  (*cinfo->cconvert->color_convert) (cinfo, upsample->color_buf,

+				     (JDIMENSION) upsample->next_row_out,

+				     output_buf + *out_row_ctr,

+				     (int) num_rows);

+

+  /* Adjust counts */

+  *out_row_ctr += num_rows;

+  upsample->rows_to_go -= num_rows;

+  upsample->next_row_out += num_rows;

+  /* When the buffer is emptied, declare this input row group consumed */

+  if (upsample->next_row_out >= cinfo->max_v_samp_factor)

+    (*in_row_group_ctr)++;

+}

+

+

+/*

+ * These are the routines invoked by sep_upsample to upsample pixel values

+ * of a single component.  One row group is processed per call.

+ */

+

+

+/*

+ * For full-size components, we just make color_buf[ci] point at the

+ * input buffer, and thus avoid copying any data.  Note that this is

+ * safe only because sep_upsample doesn't declare the input row group

+ * "consumed" until we are done color converting and emitting it.

+ */

+

+METHODDEF void

+fullsize_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		   JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  *output_data_ptr = input_data;

+}

+

+

+/*

+ * This is a no-op version used for "uninteresting" components.

+ * These components will not be referenced by color conversion.

+ */

+

+METHODDEF void

+noop_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  *output_data_ptr = NULL;	/* safety check */

+}

+

+

+/*

+ * This version handles any integral sampling ratios.

+ * This is not used for typical JPEG files, so it need not be fast.

+ * Nor, for that matter, is it particularly accurate: the algorithm is

+ * simple replication of the input pixel onto the corresponding output

+ * pixels.  The hi-falutin sampling literature refers to this as a

+ * "box filter".  A box filter tends to introduce visible artifacts,

+ * so if you are actually going to use 3:1 or 4:1 sampling ratios

+ * you would be well advised to improve this code.

+ */

+

+METHODDEF void

+int_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	      JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  my_upsample_ptr upsample = (my_upsample_ptr) cinfo->upsample;

+  JSAMPARRAY output_data = *output_data_ptr;

+  register JSAMPROW inptr, outptr;

+  register JSAMPLE invalue;

+  register int h;

+  JSAMPROW outend;

+  int h_expand, v_expand;

+  int inrow, outrow;

+

+  h_expand = upsample->h_expand[compptr->component_index];

+  v_expand = upsample->v_expand[compptr->component_index];

+

+  inrow = outrow = 0;

+  while (outrow < cinfo->max_v_samp_factor) {

+    /* Generate one output row with proper horizontal expansion */

+    inptr = input_data[inrow];

+    outptr = output_data[outrow];

+    outend = outptr + cinfo->output_width;

+    while (outptr < outend) {

+      invalue = *inptr++;	/* don't need GETJSAMPLE() here */

+      for (h = h_expand; h > 0; h--) {

+	*outptr++ = invalue;

+      }

+    }

+    /* Generate any additional output rows by duplicating the first one */

+    if (v_expand > 1) {

+      jcopy_sample_rows(output_data, outrow, output_data, outrow+1,

+			v_expand-1, cinfo->output_width);

+    }

+    inrow++;

+    outrow += v_expand;

+  }

+}

+

+

+/*

+ * Fast processing for the common case of 2:1 horizontal and 1:1 vertical.

+ * It's still a box filter.

+ */

+

+METHODDEF void

+h2v1_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  JSAMPARRAY output_data = *output_data_ptr;

+  register JSAMPROW inptr, outptr;

+  register JSAMPLE invalue;

+  JSAMPROW outend;

+  int inrow;

+

+  for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {

+    inptr = input_data[inrow];

+    outptr = output_data[inrow];

+    outend = outptr + cinfo->output_width;

+    while (outptr < outend) {

+      invalue = *inptr++;	/* don't need GETJSAMPLE() here */

+      *outptr++ = invalue;

+      *outptr++ = invalue;

+    }

+  }

+}

+

+

+/*

+ * Fast processing for the common case of 2:1 horizontal and 2:1 vertical.

+ * It's still a box filter.

+ */

+

+METHODDEF void

+h2v2_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  JSAMPARRAY output_data = *output_data_ptr;

+  register JSAMPROW inptr, outptr;

+  register JSAMPLE invalue;

+  JSAMPROW outend;

+  int inrow, outrow;

+

+  inrow = outrow = 0;

+  while (outrow < cinfo->max_v_samp_factor) {

+    inptr = input_data[inrow];

+    outptr = output_data[outrow];

+    outend = outptr + cinfo->output_width;

+    while (outptr < outend) {

+      invalue = *inptr++;	/* don't need GETJSAMPLE() here */

+      *outptr++ = invalue;

+      *outptr++ = invalue;

+    }

+    jcopy_sample_rows(output_data, outrow, output_data, outrow+1,

+		      1, cinfo->output_width);

+    inrow++;

+    outrow += 2;

+  }

+}

+

+

+/*

+ * Fancy processing for the common case of 2:1 horizontal and 1:1 vertical.

+ *

+ * The upsampling algorithm is linear interpolation between pixel centers,

+ * also known as a "triangle filter".  This is a good compromise between

+ * speed and visual quality.  The centers of the output pixels are 1/4 and 3/4

+ * of the way between input pixel centers.

+ *

+ * A note about the "bias" calculations: when rounding fractional values to

+ * integer, we do not want to always round 0.5 up to the next integer.

+ * If we did that, we'd introduce a noticeable bias towards larger values.

+ * Instead, this code is arranged so that 0.5 will be rounded up or down at

+ * alternate pixel locations (a simple ordered dither pattern).

+ */

+

+METHODDEF void

+h2v1_fancy_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		     JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  JSAMPARRAY output_data = *output_data_ptr;

+  register JSAMPROW inptr, outptr;

+  register int invalue;

+  register JDIMENSION colctr;

+  int inrow;

+

+  for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {

+    inptr = input_data[inrow];

+    outptr = output_data[inrow];

+    /* Special case for first column */

+    invalue = GETJSAMPLE(*inptr++);

+    *outptr++ = (JSAMPLE) invalue;

+    *outptr++ = (JSAMPLE) ((invalue * 3 + GETJSAMPLE(*inptr) + 2) >> 2);

+

+    for (colctr = compptr->downsampled_width - 2; colctr > 0; colctr--) {

+      /* General case: 3/4 * nearer pixel + 1/4 * further pixel */

+      invalue = GETJSAMPLE(*inptr++) * 3;

+      *outptr++ = (JSAMPLE) ((invalue + GETJSAMPLE(inptr[-2]) + 1) >> 2);

+      *outptr++ = (JSAMPLE) ((invalue + GETJSAMPLE(*inptr) + 2) >> 2);

+    }

+

+    /* Special case for last column */

+    invalue = GETJSAMPLE(*inptr);

+    *outptr++ = (JSAMPLE) ((invalue * 3 + GETJSAMPLE(inptr[-1]) + 1) >> 2);

+    *outptr++ = (JSAMPLE) invalue;

+  }

+}

+

+

+/*

+ * Fancy processing for the common case of 2:1 horizontal and 2:1 vertical.

+ * Again a triangle filter; see comments for h2v1 case, above.

+ *

+ * It is OK for us to reference the adjacent input rows because we demanded

+ * context from the main buffer controller (see initialization code).

+ */

+

+METHODDEF void

+h2v2_fancy_upsample (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		     JSAMPARRAY input_data, JSAMPARRAY * output_data_ptr)

+{

+  JSAMPARRAY output_data = *output_data_ptr;

+  register JSAMPROW inptr0, inptr1, outptr;

+#if BITS_IN_JSAMPLE == 8

+  register int thiscolsum, lastcolsum, nextcolsum;

+#else

+  register INT32 thiscolsum, lastcolsum, nextcolsum;

+#endif

+  register JDIMENSION colctr;

+  int inrow, outrow, v;

+

+  inrow = outrow = 0;

+  while (outrow < cinfo->max_v_samp_factor) {

+    for (v = 0; v < 2; v++) {

+      /* inptr0 points to nearest input row, inptr1 points to next nearest */

+      inptr0 = input_data[inrow];

+      if (v == 0)		/* next nearest is row above */

+	inptr1 = input_data[inrow-1];

+      else			/* next nearest is row below */

+	inptr1 = input_data[inrow+1];

+      outptr = output_data[outrow++];

+

+      /* Special case for first column */

+      thiscolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++);

+      nextcolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++);

+      *outptr++ = (JSAMPLE) ((thiscolsum * 4 + 8) >> 4);

+      *outptr++ = (JSAMPLE) ((thiscolsum * 3 + nextcolsum + 7) >> 4);

+      lastcolsum = thiscolsum; thiscolsum = nextcolsum;

+

+      for (colctr = compptr->downsampled_width - 2; colctr > 0; colctr--) {

+	/* General case: 3/4 * nearer pixel + 1/4 * further pixel in each */

+	/* dimension, thus 9/16, 3/16, 3/16, 1/16 overall */

+	nextcolsum = GETJSAMPLE(*inptr0++) * 3 + GETJSAMPLE(*inptr1++);

+	*outptr++ = (JSAMPLE) ((thiscolsum * 3 + lastcolsum + 8) >> 4);

+	*outptr++ = (JSAMPLE) ((thiscolsum * 3 + nextcolsum + 7) >> 4);

+	lastcolsum = thiscolsum; thiscolsum = nextcolsum;

+      }

+

+      /* Special case for last column */

+      *outptr++ = (JSAMPLE) ((thiscolsum * 3 + lastcolsum + 8) >> 4);

+      *outptr++ = (JSAMPLE) ((thiscolsum * 4 + 7) >> 4);

+    }

+    inrow++;

+  }

+}

+

+

+/*

+ * Module initialization routine for upsampling.

+ */

+

+GLOBAL void

+jinit_upsampler (j_decompress_ptr cinfo)

+{

+  my_upsample_ptr upsample;

+  int ci;

+  jpeg_component_info * compptr;

+  boolean need_buffer, do_fancy;

+  int h_in_group, v_in_group, h_out_group, v_out_group;

+

+  upsample = (my_upsample_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_upsampler));

+  cinfo->upsample = (struct jpeg_upsampler *) upsample;

+  upsample->pub.start_pass = start_pass_upsample;

+  upsample->pub.upsample = sep_upsample;

+  upsample->pub.need_context_rows = FALSE; /* until we find out differently */

+

+  if (cinfo->CCIR601_sampling)	/* this isn't supported */

+    ERREXIT(cinfo, JERR_CCIR601_NOTIMPL);

+

+  /* jdmainct.c doesn't support context rows when min_DCT_scaled_size = 1,

+   * so don't ask for it.

+   */

+  do_fancy = cinfo->do_fancy_upsampling && cinfo->min_DCT_scaled_size > 1;

+

+  /* Verify we can handle the sampling factors, select per-component methods,

+   * and create storage as needed.

+   */

+  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

+       ci++, compptr++) {

+    /* Compute size of an "input group" after IDCT scaling.  This many samples

+     * are to be converted to max_h_samp_factor * max_v_samp_factor pixels.

+     */

+    h_in_group = (compptr->h_samp_factor * compptr->DCT_scaled_size) /

+		 cinfo->min_DCT_scaled_size;

+    v_in_group = (compptr->v_samp_factor * compptr->DCT_scaled_size) /

+		 cinfo->min_DCT_scaled_size;

+    h_out_group = cinfo->max_h_samp_factor;

+    v_out_group = cinfo->max_v_samp_factor;

+    upsample->rowgroup_height[ci] = v_in_group; /* save for use later */

+    need_buffer = TRUE;

+    if (! compptr->component_needed) {

+      /* Don't bother to upsample an uninteresting component. */

+      upsample->methods[ci] = noop_upsample;

+      need_buffer = FALSE;

+    } else if (h_in_group == h_out_group && v_in_group == v_out_group) {

+      /* Fullsize components can be processed without any work. */

+      upsample->methods[ci] = fullsize_upsample;

+      need_buffer = FALSE;

+    } else if (h_in_group * 2 == h_out_group &&

+	       v_in_group == v_out_group) {

+      /* Special cases for 2h1v upsampling */

+      if (do_fancy && compptr->downsampled_width > 2)

+	upsample->methods[ci] = h2v1_fancy_upsample;

+      else

+	upsample->methods[ci] = h2v1_upsample;

+    } else if (h_in_group * 2 == h_out_group &&

+	       v_in_group * 2 == v_out_group) {

+      /* Special cases for 2h2v upsampling */

+      if (do_fancy && compptr->downsampled_width > 2) {

+	upsample->methods[ci] = h2v2_fancy_upsample;

+	upsample->pub.need_context_rows = TRUE;

+      } else

+	upsample->methods[ci] = h2v2_upsample;

+    } else if ((h_out_group % h_in_group) == 0 &&

+	       (v_out_group % v_in_group) == 0) {

+      /* Generic integral-factors upsampling method */

+      upsample->methods[ci] = int_upsample;

+      upsample->h_expand[ci] = (UINT8) (h_out_group / h_in_group);

+      upsample->v_expand[ci] = (UINT8) (v_out_group / v_in_group);

+    } else

+      ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);

+    if (need_buffer) {

+      upsample->color_buf[ci] = (*cinfo->mem->alloc_sarray)

+	((j_common_ptr) cinfo, JPOOL_IMAGE,

+	 (JDIMENSION) jround_up((long) cinfo->output_width,

+				(long) cinfo->max_h_samp_factor),

+	 (JDIMENSION) cinfo->max_v_samp_factor);

+    }

+  }

+}

diff --git a/code/jpeg-6/jdtrans.c b/code/jpeg-6/jdtrans.c
new file mode 100755
index 0000000..eb873e0
--- /dev/null
+++ b/code/jpeg-6/jdtrans.c
@@ -0,0 +1,122 @@
+/*

+ * jdtrans.c

+ *

+ * Copyright (C) 1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains library routines for transcoding decompression,

+ * that is, reading raw DCT coefficient arrays from an input JPEG file.

+ * The routines in jdapimin.c will also be needed by a transcoder.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/* Forward declarations */

+LOCAL void transdecode_master_selection JPP((j_decompress_ptr cinfo));

+

+

+/*

+ * Read the coefficient arrays from a JPEG file.

+ * jpeg_read_header must be completed before calling this.

+ *

+ * The entire image is read into a set of virtual coefficient-block arrays,

+ * one per component.  The return value is a pointer to the array of

+ * virtual-array descriptors.  These can be manipulated directly via the

+ * JPEG memory manager, or handed off to jpeg_write_coefficients().

+ * To release the memory occupied by the virtual arrays, call

+ * jpeg_finish_decompress() when done with the data.

+ *

+ * Returns NULL if suspended.  This case need be checked only if

+ * a suspending data source is used.

+ */

+

+GLOBAL jvirt_barray_ptr *

+jpeg_read_coefficients (j_decompress_ptr cinfo)

+{

+  if (cinfo->global_state == DSTATE_READY) {

+    /* First call: initialize active modules */

+    transdecode_master_selection(cinfo);

+    cinfo->global_state = DSTATE_RDCOEFS;

+  } else if (cinfo->global_state != DSTATE_RDCOEFS)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  /* Absorb whole file into the coef buffer */

+  for (;;) {

+    int retcode;

+    /* Call progress monitor hook if present */

+    if (cinfo->progress != NULL)

+      (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

+    /* Absorb some more input */

+    retcode = (*cinfo->inputctl->consume_input) (cinfo);

+    if (retcode == JPEG_SUSPENDED)

+      return NULL;

+    if (retcode == JPEG_REACHED_EOI)

+      break;

+    /* Advance progress counter if appropriate */

+    if (cinfo->progress != NULL &&

+	(retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) {

+      if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) {

+	/* startup underestimated number of scans; ratchet up one scan */

+	cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows;

+      }

+    }

+  }

+  /* Set state so that jpeg_finish_decompress does the right thing */

+  cinfo->global_state = DSTATE_STOPPING;

+  return cinfo->coef->coef_arrays;

+}

+

+

+/*

+ * Master selection of decompression modules for transcoding.

+ * This substitutes for jdmaster.c's initialization of the full decompressor.

+ */

+

+LOCAL void

+transdecode_master_selection (j_decompress_ptr cinfo)

+{

+  /* Entropy decoding: either Huffman or arithmetic coding. */

+  if (cinfo->arith_code) {

+    ERREXIT(cinfo, JERR_ARITH_NOTIMPL);

+  } else {

+    if (cinfo->progressive_mode) {

+#ifdef D_PROGRESSIVE_SUPPORTED

+      jinit_phuff_decoder(cinfo);

+#else

+      ERREXIT(cinfo, JERR_NOT_COMPILED);

+#endif

+    } else

+      jinit_huff_decoder(cinfo);

+  }

+

+  /* Always get a full-image coefficient buffer. */

+  jinit_d_coef_controller(cinfo, TRUE);

+

+  /* We can now tell the memory manager to allocate virtual arrays. */

+  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);

+

+  /* Initialize input side of decompressor to consume first scan. */

+  (*cinfo->inputctl->start_input_pass) (cinfo);

+

+  /* Initialize progress monitoring. */

+  if (cinfo->progress != NULL) {

+    int nscans;

+    /* Estimate number of scans to set pass_limit. */

+    if (cinfo->progressive_mode) {

+      /* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */

+      nscans = 2 + 3 * cinfo->num_components;

+    } else if (cinfo->inputctl->has_multiple_scans) {

+      /* For a nonprogressive multiscan file, estimate 1 scan per component. */

+      nscans = cinfo->num_components;

+    } else {

+      nscans = 1;

+    }

+    cinfo->progress->pass_counter = 0L;

+    cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans;

+    cinfo->progress->completed_passes = 0;

+    cinfo->progress->total_passes = 1;

+  }

+}

diff --git a/code/jpeg-6/jerror.c b/code/jpeg-6/jerror.c
new file mode 100755
index 0000000..aff0a79
--- /dev/null
+++ b/code/jpeg-6/jerror.c
@@ -0,0 +1,232 @@
+/*

+ * jerror.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains simple error-reporting and trace-message routines.

+ * These are suitable for Unix-like systems and others where writing to

+ * stderr is the right thing to do.  Many applications will want to replace

+ * some or all of these routines.

+ *

+ * These routines are used by both the compression and decompression code.

+ */

+

+/* this is not a core library module, so it doesn't define JPEG_INTERNALS */

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jversion.h"

+#include "jerror.h"

+

+#include "../renderer/tr_local.h"

+

+#ifndef EXIT_FAILURE		/* define exit() codes if not provided */

+#define EXIT_FAILURE  1

+#endif

+

+

+/*

+ * Create the message string table.

+ * We do this from the master message list in jerror.h by re-reading

+ * jerror.h with a suitable definition for macro JMESSAGE.

+ * The message table is made an external symbol just in case any applications

+ * want to refer to it directly.

+ */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_std_message_table	jMsgTable

+#endif

+

+#define JMESSAGE(code,string)	string ,

+

+const char * const jpeg_std_message_table[] = {

+#include "jerror.h"

+  NULL

+};

+

+

+/*

+ * Error exit handler: must not return to caller.

+ *

+ * Applications may override this if they want to get control back after

+ * an error.  Typically one would longjmp somewhere instead of exiting.

+ * The setjmp buffer can be made a private field within an expanded error

+ * handler object.  Note that the info needed to generate an error message

+ * is stored in the error object, so you can generate the message now or

+ * later, at your convenience.

+ * You should make sure that the JPEG object is cleaned up (with jpeg_abort

+ * or jpeg_destroy) at some point.

+ */

+

+METHODDEF void

+error_exit (j_common_ptr cinfo)

+{

+  char buffer[JMSG_LENGTH_MAX];

+

+  /* Create the message */

+  (*cinfo->err->format_message) (cinfo, buffer);

+

+  /* Let the memory manager delete any temp files before we die */

+  jpeg_destroy(cinfo);

+

+  ri.Error( ERR_FATAL, "%s\n", buffer );

+}

+

+

+/*

+ * Actual output of an error or trace message.

+ * Applications may override this method to send JPEG messages somewhere

+ * other than stderr.

+ */

+

+METHODDEF void

+output_message (j_common_ptr cinfo)

+{

+  char buffer[JMSG_LENGTH_MAX];

+

+  /* Create the message */

+  (*cinfo->err->format_message) (cinfo, buffer);

+

+  /* Send it to stderr, adding a newline */

+  ri.Printf(PRINT_ALL, "%s\n", buffer);

+}

+

+

+/*

+ * Decide whether to emit a trace or warning message.

+ * msg_level is one of:

+ *   -1: recoverable corrupt-data warning, may want to abort.

+ *    0: important advisory messages (always display to user).

+ *    1: first level of tracing detail.

+ *    2,3,...: successively more detailed tracing messages.

+ * An application might override this method if it wanted to abort on warnings

+ * or change the policy about which messages to display.

+ */

+

+METHODDEF void

+emit_message (j_common_ptr cinfo, int msg_level)

+{

+  struct jpeg_error_mgr * err = cinfo->err;

+

+  if (msg_level < 0) {

+    /* It's a warning message.  Since corrupt files may generate many warnings,

+     * the policy implemented here is to show only the first warning,

+     * unless trace_level >= 3.

+     */

+    if (err->num_warnings == 0 || err->trace_level >= 3)

+      (*err->output_message) (cinfo);

+    /* Always count warnings in num_warnings. */

+    err->num_warnings++;

+  } else {

+    /* It's a trace message.  Show it if trace_level >= msg_level. */

+    if (err->trace_level >= msg_level)

+      (*err->output_message) (cinfo);

+  }

+}

+

+

+/*

+ * Format a message string for the most recent JPEG error or message.

+ * The message is stored into buffer, which should be at least JMSG_LENGTH_MAX

+ * characters.  Note that no '\n' character is added to the string.

+ * Few applications should need to override this method.

+ */

+

+METHODDEF void

+format_message (j_common_ptr cinfo, char * buffer)

+{

+  struct jpeg_error_mgr * err = cinfo->err;

+  int msg_code = err->msg_code;

+  const char * msgtext = NULL;

+  const char * msgptr;

+  char ch;

+  boolean isstring;

+

+  /* Look up message string in proper table */

+  if (msg_code > 0 && msg_code <= err->last_jpeg_message) {

+    msgtext = err->jpeg_message_table[msg_code];

+  } else if (err->addon_message_table != NULL &&

+	     msg_code >= err->first_addon_message &&

+	     msg_code <= err->last_addon_message) {

+    msgtext = err->addon_message_table[msg_code - err->first_addon_message];

+  }

+

+  /* Defend against bogus message number */

+  if (msgtext == NULL) {

+    err->msg_parm.i[0] = msg_code;

+    msgtext = err->jpeg_message_table[0];

+  }

+

+  /* Check for string parameter, as indicated by %s in the message text */

+  isstring = FALSE;

+  msgptr = msgtext;

+  while ((ch = *msgptr++) != '\0') {

+    if (ch == '%') {

+      if (*msgptr == 's') isstring = TRUE;

+      break;

+    }

+  }

+

+  /* Format the message into the passed buffer */

+  if (isstring)

+    sprintf(buffer, msgtext, err->msg_parm.s);

+  else

+    sprintf(buffer, msgtext,

+	    err->msg_parm.i[0], err->msg_parm.i[1],

+	    err->msg_parm.i[2], err->msg_parm.i[3],

+	    err->msg_parm.i[4], err->msg_parm.i[5],

+	    err->msg_parm.i[6], err->msg_parm.i[7]);

+}

+

+

+/*

+ * Reset error state variables at start of a new image.

+ * This is called during compression startup to reset trace/error

+ * processing to default state, without losing any application-specific

+ * method pointers.  An application might possibly want to override

+ * this method if it has additional error processing state.

+ */

+

+METHODDEF void

+reset_error_mgr (j_common_ptr cinfo)

+{

+  cinfo->err->num_warnings = 0;

+  /* trace_level is not reset since it is an application-supplied parameter */

+  cinfo->err->msg_code = 0;	/* may be useful as a flag for "no error" */

+}

+

+

+/*

+ * Fill in the standard error-handling methods in a jpeg_error_mgr object.

+ * Typical call is:

+ *	struct jpeg_compress_struct cinfo;

+ *	struct jpeg_error_mgr err;

+ *

+ *	cinfo.err = jpeg_std_error(&err);

+ * after which the application may override some of the methods.

+ */

+

+GLOBAL struct jpeg_error_mgr *

+jpeg_std_error (struct jpeg_error_mgr * err)

+{

+  err->error_exit = error_exit;

+  err->emit_message = emit_message;

+  err->output_message = output_message;

+  err->format_message = format_message;

+  err->reset_error_mgr = reset_error_mgr;

+

+  err->trace_level = 0;		/* default = no tracing */

+  err->num_warnings = 0;	/* no warnings emitted yet */

+  err->msg_code = 0;		/* may be useful as a flag for "no error" */

+

+  /* Initialize message table pointers */

+  err->jpeg_message_table = jpeg_std_message_table;

+  err->last_jpeg_message = (int) JMSG_LASTMSGCODE - 1;

+

+  err->addon_message_table = NULL;

+  err->first_addon_message = 0;	/* for safety */

+  err->last_addon_message = 0;

+

+  return err;

+}

diff --git a/code/jpeg-6/jerror.h b/code/jpeg-6/jerror.h
new file mode 100755
index 0000000..0ffb8b4
--- /dev/null
+++ b/code/jpeg-6/jerror.h
@@ -0,0 +1,273 @@
+/*

+ * jerror.h

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file defines the error and message codes for the JPEG library.

+ * Edit this file to add new codes, or to translate the message strings to

+ * some other language.

+ * A set of error-reporting macros are defined too.  Some applications using

+ * the JPEG library may wish to include this file to get the error codes

+ * and/or the macros.

+ */

+

+/*

+ * To define the enum list of message codes, include this file without

+ * defining macro JMESSAGE.  To create a message string table, include it

+ * again with a suitable JMESSAGE definition (see jerror.c for an example).

+ */

+#ifndef JMESSAGE

+#ifndef JERROR_H

+/* First time through, define the enum list */

+#define JMAKE_ENUM_LIST

+#else

+/* Repeated inclusions of this file are no-ops unless JMESSAGE is defined */

+#define JMESSAGE(code,string)

+#endif /* JERROR_H */

+#endif /* JMESSAGE */

+

+#ifdef JMAKE_ENUM_LIST

+

+typedef enum {

+

+#define JMESSAGE(code,string)	code ,

+

+#endif /* JMAKE_ENUM_LIST */

+

+JMESSAGE(JMSG_NOMESSAGE, "Bogus message code %d") /* Must be first entry! */

+

+/* For maintenance convenience, list is alphabetical by message code name */

+JMESSAGE(JERR_ARITH_NOTIMPL,

+	 "Sorry, there are legal restrictions on arithmetic coding")

+JMESSAGE(JERR_BAD_ALIGN_TYPE, "ALIGN_TYPE is wrong, please fix")

+JMESSAGE(JERR_BAD_ALLOC_CHUNK, "MAX_ALLOC_CHUNK is wrong, please fix")

+JMESSAGE(JERR_BAD_BUFFER_MODE, "Bogus buffer control mode")

+JMESSAGE(JERR_BAD_COMPONENT_ID, "Invalid component ID %d in SOS")

+JMESSAGE(JERR_BAD_DCTSIZE, "IDCT output block size %d not supported")

+JMESSAGE(JERR_BAD_IN_COLORSPACE, "Bogus input colorspace")

+JMESSAGE(JERR_BAD_J_COLORSPACE, "Bogus JPEG colorspace")

+JMESSAGE(JERR_BAD_LENGTH, "Bogus marker length")

+JMESSAGE(JERR_BAD_MCU_SIZE, "Sampling factors too large for interleaved scan")

+JMESSAGE(JERR_BAD_POOL_ID, "Invalid memory pool code %d")

+JMESSAGE(JERR_BAD_PRECISION, "Unsupported JPEG data precision %d")

+JMESSAGE(JERR_BAD_PROGRESSION,

+	 "Invalid progressive parameters Ss=%d Se=%d Ah=%d Al=%d")

+JMESSAGE(JERR_BAD_PROG_SCRIPT,

+	 "Invalid progressive parameters at scan script entry %d")

+JMESSAGE(JERR_BAD_SAMPLING, "Bogus sampling factors")

+JMESSAGE(JERR_BAD_SCAN_SCRIPT, "Invalid scan script at entry %d")

+JMESSAGE(JERR_BAD_STATE, "Improper call to JPEG library in state %d")

+JMESSAGE(JERR_BAD_VIRTUAL_ACCESS, "Bogus virtual array access")

+JMESSAGE(JERR_BUFFER_SIZE, "Buffer passed to JPEG library is too small")

+JMESSAGE(JERR_CANT_SUSPEND, "Suspension not allowed here")

+JMESSAGE(JERR_CCIR601_NOTIMPL, "CCIR601 sampling not implemented yet")

+JMESSAGE(JERR_COMPONENT_COUNT, "Too many color components: %d, max %d")

+JMESSAGE(JERR_CONVERSION_NOTIMPL, "Unsupported color conversion request")

+JMESSAGE(JERR_DAC_INDEX, "Bogus DAC index %d")

+JMESSAGE(JERR_DAC_VALUE, "Bogus DAC value 0x%x")

+JMESSAGE(JERR_DHT_COUNTS, "Bogus DHT counts")

+JMESSAGE(JERR_DHT_INDEX, "Bogus DHT index %d")

+JMESSAGE(JERR_DQT_INDEX, "Bogus DQT index %d")

+JMESSAGE(JERR_EMPTY_IMAGE, "Empty JPEG image (DNL not supported)")

+JMESSAGE(JERR_EMS_READ, "Read from EMS failed")

+JMESSAGE(JERR_EMS_WRITE, "Write to EMS failed")

+JMESSAGE(JERR_EOI_EXPECTED, "Didn't expect more than one scan")

+JMESSAGE(JERR_FILE_READ, "Input file read error")

+JMESSAGE(JERR_FILE_WRITE, "Output file write error --- out of disk space?")

+JMESSAGE(JERR_FRACT_SAMPLE_NOTIMPL, "Fractional sampling not implemented yet")

+JMESSAGE(JERR_HUFF_CLEN_OVERFLOW, "Huffman code size table overflow")

+JMESSAGE(JERR_HUFF_MISSING_CODE, "Missing Huffman code table entry")

+JMESSAGE(JERR_IMAGE_TOO_BIG, "Maximum supported image dimension is %u pixels")

+JMESSAGE(JERR_INPUT_EMPTY, "Empty input file")

+JMESSAGE(JERR_INPUT_EOF, "Premature end of input file")

+JMESSAGE(JERR_MISMATCHED_QUANT_TABLE,

+	 "Cannot transcode due to multiple use of quantization table %d")

+JMESSAGE(JERR_MISSING_DATA, "Scan script does not transmit all data")

+JMESSAGE(JERR_MODE_CHANGE, "Invalid color quantization mode change")

+JMESSAGE(JERR_NOTIMPL, "Not implemented yet")

+JMESSAGE(JERR_NOT_COMPILED, "Requested feature was omitted at compile time")

+JMESSAGE(JERR_NO_BACKING_STORE, "Backing store not supported")

+JMESSAGE(JERR_NO_HUFF_TABLE, "Huffman table 0x%02x was not defined")

+JMESSAGE(JERR_NO_IMAGE, "JPEG datastream contains no image")

+JMESSAGE(JERR_NO_QUANT_TABLE, "Quantization table 0x%02x was not defined")

+JMESSAGE(JERR_NO_SOI, "Not a JPEG file: starts with 0x%02x 0x%02x")

+JMESSAGE(JERR_OUT_OF_MEMORY, "Insufficient memory (case %d)")

+JMESSAGE(JERR_QUANT_COMPONENTS,

+	 "Cannot quantize more than %d color components")

+JMESSAGE(JERR_QUANT_FEW_COLORS, "Cannot quantize to fewer than %d colors")

+JMESSAGE(JERR_QUANT_MANY_COLORS, "Cannot quantize to more than %d colors")

+JMESSAGE(JERR_SOF_DUPLICATE, "Invalid JPEG file structure: two SOF markers")

+JMESSAGE(JERR_SOF_NO_SOS, "Invalid JPEG file structure: missing SOS marker")

+JMESSAGE(JERR_SOF_UNSUPPORTED, "Unsupported JPEG process: SOF type 0x%02x")

+JMESSAGE(JERR_SOI_DUPLICATE, "Invalid JPEG file structure: two SOI markers")

+JMESSAGE(JERR_SOS_NO_SOF, "Invalid JPEG file structure: SOS before SOF")

+JMESSAGE(JERR_TFILE_CREATE, "Failed to create temporary file %s")

+JMESSAGE(JERR_TFILE_READ, "Read failed on temporary file")

+JMESSAGE(JERR_TFILE_SEEK, "Seek failed on temporary file")

+JMESSAGE(JERR_TFILE_WRITE,

+	 "Write failed on temporary file --- out of disk space?")

+JMESSAGE(JERR_TOO_LITTLE_DATA, "Application transferred too few scanlines")

+JMESSAGE(JERR_UNKNOWN_MARKER, "Unsupported marker type 0x%02x")

+JMESSAGE(JERR_VIRTUAL_BUG, "Virtual array controller messed up")

+JMESSAGE(JERR_WIDTH_OVERFLOW, "Image too wide for this implementation")

+JMESSAGE(JERR_XMS_READ, "Read from XMS failed")

+JMESSAGE(JERR_XMS_WRITE, "Write to XMS failed")

+JMESSAGE(JMSG_COPYRIGHT, JCOPYRIGHT)

+JMESSAGE(JMSG_VERSION, JVERSION)

+JMESSAGE(JTRC_16BIT_TABLES,

+	 "Caution: quantization tables are too coarse for baseline JPEG")

+JMESSAGE(JTRC_ADOBE,

+	 "Adobe APP14 marker: version %d, flags 0x%04x 0x%04x, transform %d")

+JMESSAGE(JTRC_APP0, "Unknown APP0 marker (not JFIF), length %u")

+JMESSAGE(JTRC_APP14, "Unknown APP14 marker (not Adobe), length %u")

+JMESSAGE(JTRC_DAC, "Define Arithmetic Table 0x%02x: 0x%02x")

+JMESSAGE(JTRC_DHT, "Define Huffman Table 0x%02x")

+JMESSAGE(JTRC_DQT, "Define Quantization Table %d  precision %d")

+JMESSAGE(JTRC_DRI, "Define Restart Interval %u")

+JMESSAGE(JTRC_EMS_CLOSE, "Freed EMS handle %u")

+JMESSAGE(JTRC_EMS_OPEN, "Obtained EMS handle %u")

+JMESSAGE(JTRC_EOI, "End Of Image")

+JMESSAGE(JTRC_HUFFBITS, "        %3d %3d %3d %3d %3d %3d %3d %3d")

+JMESSAGE(JTRC_JFIF, "JFIF APP0 marker, density %dx%d  %d")

+JMESSAGE(JTRC_JFIF_BADTHUMBNAILSIZE,

+	 "Warning: thumbnail image size does not match data length %u")

+JMESSAGE(JTRC_JFIF_MINOR, "Unknown JFIF minor revision number %d.%02d")

+JMESSAGE(JTRC_JFIF_THUMBNAIL, "    with %d x %d thumbnail image")

+JMESSAGE(JTRC_MISC_MARKER, "Skipping marker 0x%02x, length %u")

+JMESSAGE(JTRC_PARMLESS_MARKER, "Unexpected marker 0x%02x")

+JMESSAGE(JTRC_QUANTVALS, "        %4u %4u %4u %4u %4u %4u %4u %4u")

+JMESSAGE(JTRC_QUANT_3_NCOLORS, "Quantizing to %d = %d*%d*%d colors")

+JMESSAGE(JTRC_QUANT_NCOLORS, "Quantizing to %d colors")

+JMESSAGE(JTRC_QUANT_SELECTED, "Selected %d colors for quantization")

+JMESSAGE(JTRC_RECOVERY_ACTION, "At marker 0x%02x, recovery action %d")

+JMESSAGE(JTRC_RST, "RST%d")

+JMESSAGE(JTRC_SMOOTH_NOTIMPL,

+	 "Smoothing not supported with nonstandard sampling ratios")

+JMESSAGE(JTRC_SOF, "Start Of Frame 0x%02x: width=%u, height=%u, components=%d")

+JMESSAGE(JTRC_SOF_COMPONENT, "    Component %d: %dhx%dv q=%d")

+JMESSAGE(JTRC_SOI, "Start of Image")

+JMESSAGE(JTRC_SOS, "Start Of Scan: %d components")

+JMESSAGE(JTRC_SOS_COMPONENT, "    Component %d: dc=%d ac=%d")

+JMESSAGE(JTRC_SOS_PARAMS, "  Ss=%d, Se=%d, Ah=%d, Al=%d")

+JMESSAGE(JTRC_TFILE_CLOSE, "Closed temporary file %s")

+JMESSAGE(JTRC_TFILE_OPEN, "Opened temporary file %s")

+JMESSAGE(JTRC_UNKNOWN_IDS,

+	 "Unrecognized component IDs %d %d %d, assuming YCbCr")

+JMESSAGE(JTRC_XMS_CLOSE, "Freed XMS handle %u")

+JMESSAGE(JTRC_XMS_OPEN, "Obtained XMS handle %u")

+JMESSAGE(JWRN_ADOBE_XFORM, "Unknown Adobe color transform code %d")

+JMESSAGE(JWRN_BOGUS_PROGRESSION,

+	 "Inconsistent progression sequence for component %d coefficient %d")

+JMESSAGE(JWRN_EXTRANEOUS_DATA,

+	 "Corrupt JPEG data: %u extraneous bytes before marker 0x%02x")

+JMESSAGE(JWRN_HIT_MARKER, "Corrupt JPEG data: premature end of data segment")

+JMESSAGE(JWRN_HUFF_BAD_CODE, "Corrupt JPEG data: bad Huffman code")

+JMESSAGE(JWRN_JFIF_MAJOR, "Warning: unknown JFIF revision number %d.%02d")

+JMESSAGE(JWRN_JPEG_EOF, "Premature end of JPEG file")

+JMESSAGE(JWRN_MUST_RESYNC,

+	 "Corrupt JPEG data: found marker 0x%02x instead of RST%d")

+JMESSAGE(JWRN_NOT_SEQUENTIAL, "Invalid SOS parameters for sequential JPEG")

+JMESSAGE(JWRN_TOO_MUCH_DATA, "Application transferred too many scanlines")

+

+#ifdef JMAKE_ENUM_LIST

+

+  JMSG_LASTMSGCODE

+} J_MESSAGE_CODE;

+

+#undef JMAKE_ENUM_LIST

+#endif /* JMAKE_ENUM_LIST */

+

+/* Zap JMESSAGE macro so that future re-inclusions do nothing by default */

+#undef JMESSAGE

+

+

+#ifndef JERROR_H

+#define JERROR_H

+

+/* Macros to simplify using the error and trace message stuff */

+/* The first parameter is either type of cinfo pointer */

+

+/* Fatal errors (print message and exit) */

+#define ERREXIT(cinfo,code)  \

+  ((cinfo)->err->msg_code = (code), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+#define ERREXIT1(cinfo,code,p1)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+#define ERREXIT2(cinfo,code,p1,p2)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (cinfo)->err->msg_parm.i[1] = (p2), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+#define ERREXIT3(cinfo,code,p1,p2,p3)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (cinfo)->err->msg_parm.i[1] = (p2), \

+   (cinfo)->err->msg_parm.i[2] = (p3), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+#define ERREXIT4(cinfo,code,p1,p2,p3,p4)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (cinfo)->err->msg_parm.i[1] = (p2), \

+   (cinfo)->err->msg_parm.i[2] = (p3), \

+   (cinfo)->err->msg_parm.i[3] = (p4), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+#define ERREXITS(cinfo,code,str)  \

+  ((cinfo)->err->msg_code = (code), \

+   strncpy((cinfo)->err->msg_parm.s, (str), JMSG_STR_PARM_MAX), \

+   (*(cinfo)->err->error_exit) ((j_common_ptr) (cinfo)))

+

+#define MAKESTMT(stuff)		do { stuff } while (0)

+

+/* Nonfatal errors (we can keep going, but the data is probably corrupt) */

+#define WARNMS(cinfo,code)  \

+  ((cinfo)->err->msg_code = (code), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1))

+#define WARNMS1(cinfo,code,p1)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1))

+#define WARNMS2(cinfo,code,p1,p2)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (cinfo)->err->msg_parm.i[1] = (p2), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), -1))

+

+/* Informational/debugging messages */

+#define TRACEMS(cinfo,lvl,code)  \

+  ((cinfo)->err->msg_code = (code), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)))

+#define TRACEMS1(cinfo,lvl,code,p1)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)))

+#define TRACEMS2(cinfo,lvl,code,p1,p2)  \

+  ((cinfo)->err->msg_code = (code), \

+   (cinfo)->err->msg_parm.i[0] = (p1), \

+   (cinfo)->err->msg_parm.i[1] = (p2), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)))

+#define TRACEMS3(cinfo,lvl,code,p1,p2,p3)  \

+  MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \

+	   _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); \

+	   (cinfo)->err->msg_code = (code); \

+	   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); )

+#define TRACEMS4(cinfo,lvl,code,p1,p2,p3,p4)  \

+  MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \

+	   _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); _mp[3] = (p4); \

+	   (cinfo)->err->msg_code = (code); \

+	   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); )

+#define TRACEMS8(cinfo,lvl,code,p1,p2,p3,p4,p5,p6,p7,p8)  \

+  MAKESTMT(int * _mp = (cinfo)->err->msg_parm.i; \

+	   _mp[0] = (p1); _mp[1] = (p2); _mp[2] = (p3); _mp[3] = (p4); \

+	   _mp[4] = (p5); _mp[5] = (p6); _mp[6] = (p7); _mp[7] = (p8); \

+	   (cinfo)->err->msg_code = (code); \

+	   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)); )

+#define TRACEMSS(cinfo,lvl,code,str)  \

+  ((cinfo)->err->msg_code = (code), \

+   strncpy((cinfo)->err->msg_parm.s, (str), JMSG_STR_PARM_MAX), \

+   (*(cinfo)->err->emit_message) ((j_common_ptr) (cinfo), (lvl)))

+

+#endif /* JERROR_H */

diff --git a/code/jpeg-6/jfdctflt.c b/code/jpeg-6/jfdctflt.c
new file mode 100755
index 0000000..1509b88
--- /dev/null
+++ b/code/jpeg-6/jfdctflt.c
@@ -0,0 +1,168 @@
+/*

+ * jfdctflt.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a floating-point implementation of the

+ * forward DCT (Discrete Cosine Transform).

+ *

+ * This implementation should be more accurate than either of the integer

+ * DCT implementations.  However, it may not give the same results on all

+ * machines because of differences in roundoff behavior.  Speed will depend

+ * on the hardware's floating point capacity.

+ *

+ * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT

+ * on each column.  Direct algorithms are also available, but they are

+ * much more complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on Arai, Agui, and Nakajima's algorithm for

+ * scaled DCT.  Their original paper (Trans. IEICE E-71(11):1095) is in

+ * Japanese, but the algorithm is described in the Pennebaker & Mitchell

+ * JPEG textbook (see REFERENCES section in file README).  The following code

+ * is based directly on figure 4-8 in P&M.

+ * While an 8-point DCT cannot be done in less than 11 multiplies, it is

+ * possible to arrange the computation so that many of the multiplies are

+ * simple scalings of the final outputs.  These multiplies can then be

+ * folded into the multiplications or divisions by the JPEG quantization

+ * table entries.  The AA&N method leaves only 5 multiplies and 29 adds

+ * to be done in the DCT itself.

+ * The primary disadvantage of this method is that with a fixed-point

+ * implementation, accuracy is lost due to imprecise representation of the

+ * scaled quantization values.  However, that problem does not arise if

+ * we use floating point arithmetic.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_FLOAT_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/*

+ * Perform the forward DCT on one block of samples.

+ */

+

+GLOBAL void

+jpeg_fdct_float (FAST_FLOAT * data)

+{

+  FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

+  FAST_FLOAT tmp10, tmp11, tmp12, tmp13;

+  FAST_FLOAT z1, z2, z3, z4, z5, z11, z13;

+  FAST_FLOAT *dataptr;

+  int ctr;

+

+  /* Pass 1: process rows. */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[0] + dataptr[7];

+    tmp7 = dataptr[0] - dataptr[7];

+    tmp1 = dataptr[1] + dataptr[6];

+    tmp6 = dataptr[1] - dataptr[6];

+    tmp2 = dataptr[2] + dataptr[5];

+    tmp5 = dataptr[2] - dataptr[5];

+    tmp3 = dataptr[3] + dataptr[4];

+    tmp4 = dataptr[3] - dataptr[4];

+    

+    /* Even part */

+    

+    tmp10 = tmp0 + tmp3;	/* phase 2 */

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[0] = tmp10 + tmp11; /* phase 3 */

+    dataptr[4] = tmp10 - tmp11;

+    

+    z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */

+    dataptr[2] = tmp13 + z1;	/* phase 5 */

+    dataptr[6] = tmp13 - z1;

+    

+    /* Odd part */

+

+    tmp10 = tmp4 + tmp5;	/* phase 2 */

+    tmp11 = tmp5 + tmp6;

+    tmp12 = tmp6 + tmp7;

+

+    /* The rotator is modified from fig 4-8 to avoid extra negations. */

+    z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */

+    z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */

+    z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */

+    z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */

+

+    z11 = tmp7 + z3;		/* phase 5 */

+    z13 = tmp7 - z3;

+

+    dataptr[5] = z13 + z2;	/* phase 6 */

+    dataptr[3] = z13 - z2;

+    dataptr[1] = z11 + z4;

+    dataptr[7] = z11 - z4;

+

+    dataptr += DCTSIZE;		/* advance pointer to next row */

+  }

+

+  /* Pass 2: process columns. */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];

+    tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];

+    tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];

+    tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];

+    tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];

+    tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];

+    tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];

+    tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];

+    

+    /* Even part */

+    

+    tmp10 = tmp0 + tmp3;	/* phase 2 */

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */

+    dataptr[DCTSIZE*4] = tmp10 - tmp11;

+    

+    z1 = (tmp12 + tmp13) * ((FAST_FLOAT) 0.707106781); /* c4 */

+    dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */

+    dataptr[DCTSIZE*6] = tmp13 - z1;

+    

+    /* Odd part */

+

+    tmp10 = tmp4 + tmp5;	/* phase 2 */

+    tmp11 = tmp5 + tmp6;

+    tmp12 = tmp6 + tmp7;

+

+    /* The rotator is modified from fig 4-8 to avoid extra negations. */

+    z5 = (tmp10 - tmp12) * ((FAST_FLOAT) 0.382683433); /* c6 */

+    z2 = ((FAST_FLOAT) 0.541196100) * tmp10 + z5; /* c2-c6 */

+    z4 = ((FAST_FLOAT) 1.306562965) * tmp12 + z5; /* c2+c6 */

+    z3 = tmp11 * ((FAST_FLOAT) 0.707106781); /* c4 */

+

+    z11 = tmp7 + z3;		/* phase 5 */

+    z13 = tmp7 - z3;

+

+    dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */

+    dataptr[DCTSIZE*3] = z13 - z2;

+    dataptr[DCTSIZE*1] = z11 + z4;

+    dataptr[DCTSIZE*7] = z11 - z4;

+

+    dataptr++;			/* advance pointer to next column */

+  }

+}

+

+#endif /* DCT_FLOAT_SUPPORTED */

diff --git a/code/jpeg-6/jfdctfst.c b/code/jpeg-6/jfdctfst.c
new file mode 100755
index 0000000..e311fc0
--- /dev/null
+++ b/code/jpeg-6/jfdctfst.c
@@ -0,0 +1,224 @@
+/*

+ * jfdctfst.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a fast, not so accurate integer implementation of the

+ * forward DCT (Discrete Cosine Transform).

+ *

+ * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT

+ * on each column.  Direct algorithms are also available, but they are

+ * much more complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on Arai, Agui, and Nakajima's algorithm for

+ * scaled DCT.  Their original paper (Trans. IEICE E-71(11):1095) is in

+ * Japanese, but the algorithm is described in the Pennebaker & Mitchell

+ * JPEG textbook (see REFERENCES section in file README).  The following code

+ * is based directly on figure 4-8 in P&M.

+ * While an 8-point DCT cannot be done in less than 11 multiplies, it is

+ * possible to arrange the computation so that many of the multiplies are

+ * simple scalings of the final outputs.  These multiplies can then be

+ * folded into the multiplications or divisions by the JPEG quantization

+ * table entries.  The AA&N method leaves only 5 multiplies and 29 adds

+ * to be done in the DCT itself.

+ * The primary disadvantage of this method is that with fixed-point math,

+ * accuracy is lost due to imprecise representation of the scaled

+ * quantization values.  The smaller the quantization table entry, the less

+ * precise the scaled value, so this implementation does worse with high-

+ * quality-setting files than with low-quality ones.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_IFAST_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/* Scaling decisions are generally the same as in the LL&M algorithm;

+ * see jfdctint.c for more details.  However, we choose to descale

+ * (right shift) multiplication products as soon as they are formed,

+ * rather than carrying additional fractional bits into subsequent additions.

+ * This compromises accuracy slightly, but it lets us save a few shifts.

+ * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)

+ * everywhere except in the multiplications proper; this saves a good deal

+ * of work on 16-bit-int machines.

+ *

+ * Again to save a few shifts, the intermediate results between pass 1 and

+ * pass 2 are not upscaled, but are represented only to integral precision.

+ *

+ * A final compromise is to represent the multiplicative constants to only

+ * 8 fractional bits, rather than 13.  This saves some shifting work on some

+ * machines, and may also reduce the cost of multiplication (since there

+ * are fewer one-bits in the constants).

+ */

+

+#define CONST_BITS  8

+

+

+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus

+ * causing a lot of useless floating-point operations at run time.

+ * To get around this we use the following pre-calculated constants.

+ * If you change CONST_BITS you may want to add appropriate values.

+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)

+ */

+

+#if CONST_BITS == 8

+#define FIX_0_382683433  ((INT32)   98)		/* FIX(0.382683433) */

+#define FIX_0_541196100  ((INT32)  139)		/* FIX(0.541196100) */

+#define FIX_0_707106781  ((INT32)  181)		/* FIX(0.707106781) */

+#define FIX_1_306562965  ((INT32)  334)		/* FIX(1.306562965) */

+#else

+#define FIX_0_382683433  FIX(0.382683433)

+#define FIX_0_541196100  FIX(0.541196100)

+#define FIX_0_707106781  FIX(0.707106781)

+#define FIX_1_306562965  FIX(1.306562965)

+#endif

+

+

+/* We can gain a little more speed, with a further compromise in accuracy,

+ * by omitting the addition in a descaling shift.  This yields an incorrectly

+ * rounded result half the time...

+ */

+

+#ifndef USE_ACCURATE_ROUNDING

+#undef DESCALE

+#define DESCALE(x,n)  RIGHT_SHIFT(x, n)

+#endif

+

+

+/* Multiply a DCTELEM variable by an INT32 constant, and immediately

+ * descale to yield a DCTELEM result.

+ */

+

+#define MULTIPLY(var,const)  ((DCTELEM) DESCALE((var) * (const), CONST_BITS))

+

+

+/*

+ * Perform the forward DCT on one block of samples.

+ */

+

+GLOBAL void

+jpeg_fdct_ifast (DCTELEM * data)

+{

+  DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

+  DCTELEM tmp10, tmp11, tmp12, tmp13;

+  DCTELEM z1, z2, z3, z4, z5, z11, z13;

+  DCTELEM *dataptr;

+  int ctr;

+  SHIFT_TEMPS

+

+  /* Pass 1: process rows. */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[0] + dataptr[7];

+    tmp7 = dataptr[0] - dataptr[7];

+    tmp1 = dataptr[1] + dataptr[6];

+    tmp6 = dataptr[1] - dataptr[6];

+    tmp2 = dataptr[2] + dataptr[5];

+    tmp5 = dataptr[2] - dataptr[5];

+    tmp3 = dataptr[3] + dataptr[4];

+    tmp4 = dataptr[3] - dataptr[4];

+    

+    /* Even part */

+    

+    tmp10 = tmp0 + tmp3;	/* phase 2 */

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[0] = tmp10 + tmp11; /* phase 3 */

+    dataptr[4] = tmp10 - tmp11;

+    

+    z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */

+    dataptr[2] = tmp13 + z1;	/* phase 5 */

+    dataptr[6] = tmp13 - z1;

+    

+    /* Odd part */

+

+    tmp10 = tmp4 + tmp5;	/* phase 2 */

+    tmp11 = tmp5 + tmp6;

+    tmp12 = tmp6 + tmp7;

+

+    /* The rotator is modified from fig 4-8 to avoid extra negations. */

+    z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */

+    z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */

+    z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */

+    z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */

+

+    z11 = tmp7 + z3;		/* phase 5 */

+    z13 = tmp7 - z3;

+

+    dataptr[5] = z13 + z2;	/* phase 6 */

+    dataptr[3] = z13 - z2;

+    dataptr[1] = z11 + z4;

+    dataptr[7] = z11 - z4;

+

+    dataptr += DCTSIZE;		/* advance pointer to next row */

+  }

+

+  /* Pass 2: process columns. */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];

+    tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];

+    tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];

+    tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];

+    tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];

+    tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];

+    tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];

+    tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];

+    

+    /* Even part */

+    

+    tmp10 = tmp0 + tmp3;	/* phase 2 */

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[DCTSIZE*0] = tmp10 + tmp11; /* phase 3 */

+    dataptr[DCTSIZE*4] = tmp10 - tmp11;

+    

+    z1 = MULTIPLY(tmp12 + tmp13, FIX_0_707106781); /* c4 */

+    dataptr[DCTSIZE*2] = tmp13 + z1; /* phase 5 */

+    dataptr[DCTSIZE*6] = tmp13 - z1;

+    

+    /* Odd part */

+

+    tmp10 = tmp4 + tmp5;	/* phase 2 */

+    tmp11 = tmp5 + tmp6;

+    tmp12 = tmp6 + tmp7;

+

+    /* The rotator is modified from fig 4-8 to avoid extra negations. */

+    z5 = MULTIPLY(tmp10 - tmp12, FIX_0_382683433); /* c6 */

+    z2 = MULTIPLY(tmp10, FIX_0_541196100) + z5; /* c2-c6 */

+    z4 = MULTIPLY(tmp12, FIX_1_306562965) + z5; /* c2+c6 */

+    z3 = MULTIPLY(tmp11, FIX_0_707106781); /* c4 */

+

+    z11 = tmp7 + z3;		/* phase 5 */

+    z13 = tmp7 - z3;

+

+    dataptr[DCTSIZE*5] = z13 + z2; /* phase 6 */

+    dataptr[DCTSIZE*3] = z13 - z2;

+    dataptr[DCTSIZE*1] = z11 + z4;

+    dataptr[DCTSIZE*7] = z11 - z4;

+

+    dataptr++;			/* advance pointer to next column */

+  }

+}

+

+#endif /* DCT_IFAST_SUPPORTED */

diff --git a/code/jpeg-6/jfdctint.c b/code/jpeg-6/jfdctint.c
new file mode 100755
index 0000000..168fd0b
--- /dev/null
+++ b/code/jpeg-6/jfdctint.c
@@ -0,0 +1,283 @@
+/*

+ * jfdctint.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a slow-but-accurate integer implementation of the

+ * forward DCT (Discrete Cosine Transform).

+ *

+ * A 2-D DCT can be done by 1-D DCT on each row followed by 1-D DCT

+ * on each column.  Direct algorithms are also available, but they are

+ * much more complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on an algorithm described in

+ *   C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT

+ *   Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics,

+ *   Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991.

+ * The primary algorithm described there uses 11 multiplies and 29 adds.

+ * We use their alternate method with 12 multiplies and 32 adds.

+ * The advantage of this method is that no data path contains more than one

+ * multiplication; this allows a very simple and accurate implementation in

+ * scaled fixed-point arithmetic, with a minimal number of shifts.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_ISLOW_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/*

+ * The poop on this scaling stuff is as follows:

+ *

+ * Each 1-D DCT step produces outputs which are a factor of sqrt(N)

+ * larger than the true DCT outputs.  The final outputs are therefore

+ * a factor of N larger than desired; since N=8 this can be cured by

+ * a simple right shift at the end of the algorithm.  The advantage of

+ * this arrangement is that we save two multiplications per 1-D DCT,

+ * because the y0 and y4 outputs need not be divided by sqrt(N).

+ * In the IJG code, this factor of 8 is removed by the quantization step

+ * (in jcdctmgr.c), NOT in this module.

+ *

+ * We have to do addition and subtraction of the integer inputs, which

+ * is no problem, and multiplication by fractional constants, which is

+ * a problem to do in integer arithmetic.  We multiply all the constants

+ * by CONST_SCALE and convert them to integer constants (thus retaining

+ * CONST_BITS bits of precision in the constants).  After doing a

+ * multiplication we have to divide the product by CONST_SCALE, with proper

+ * rounding, to produce the correct output.  This division can be done

+ * cheaply as a right shift of CONST_BITS bits.  We postpone shifting

+ * as long as possible so that partial sums can be added together with

+ * full fractional precision.

+ *

+ * The outputs of the first pass are scaled up by PASS1_BITS bits so that

+ * they are represented to better-than-integral precision.  These outputs

+ * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word

+ * with the recommended scaling.  (For 12-bit sample data, the intermediate

+ * array is INT32 anyway.)

+ *

+ * To avoid overflow of the 32-bit intermediate results in pass 2, we must

+ * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26.  Error analysis

+ * shows that the values given below are the most effective.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define CONST_BITS  13

+#define PASS1_BITS  2

+#else

+#define CONST_BITS  13

+#define PASS1_BITS  1		/* lose a little precision to avoid overflow */

+#endif

+

+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus

+ * causing a lot of useless floating-point operations at run time.

+ * To get around this we use the following pre-calculated constants.

+ * If you change CONST_BITS you may want to add appropriate values.

+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)

+ */

+

+#if CONST_BITS == 13

+#define FIX_0_298631336  ((INT32)  2446)	/* FIX(0.298631336) */

+#define FIX_0_390180644  ((INT32)  3196)	/* FIX(0.390180644) */

+#define FIX_0_541196100  ((INT32)  4433)	/* FIX(0.541196100) */

+#define FIX_0_765366865  ((INT32)  6270)	/* FIX(0.765366865) */

+#define FIX_0_899976223  ((INT32)  7373)	/* FIX(0.899976223) */

+#define FIX_1_175875602  ((INT32)  9633)	/* FIX(1.175875602) */

+#define FIX_1_501321110  ((INT32)  12299)	/* FIX(1.501321110) */

+#define FIX_1_847759065  ((INT32)  15137)	/* FIX(1.847759065) */

+#define FIX_1_961570560  ((INT32)  16069)	/* FIX(1.961570560) */

+#define FIX_2_053119869  ((INT32)  16819)	/* FIX(2.053119869) */

+#define FIX_2_562915447  ((INT32)  20995)	/* FIX(2.562915447) */

+#define FIX_3_072711026  ((INT32)  25172)	/* FIX(3.072711026) */

+#else

+#define FIX_0_298631336  FIX(0.298631336)

+#define FIX_0_390180644  FIX(0.390180644)

+#define FIX_0_541196100  FIX(0.541196100)

+#define FIX_0_765366865  FIX(0.765366865)

+#define FIX_0_899976223  FIX(0.899976223)

+#define FIX_1_175875602  FIX(1.175875602)

+#define FIX_1_501321110  FIX(1.501321110)

+#define FIX_1_847759065  FIX(1.847759065)

+#define FIX_1_961570560  FIX(1.961570560)

+#define FIX_2_053119869  FIX(2.053119869)

+#define FIX_2_562915447  FIX(2.562915447)

+#define FIX_3_072711026  FIX(3.072711026)

+#endif

+

+

+/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.

+ * For 8-bit samples with the recommended scaling, all the variable

+ * and constant values involved are no more than 16 bits wide, so a

+ * 16x16->32 bit multiply can be used instead of a full 32x32 multiply.

+ * For 12-bit samples, a full 32-bit multiplication will be needed.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define MULTIPLY(var,const)  MULTIPLY16C16(var,const)

+#else

+#define MULTIPLY(var,const)  ((var) * (const))

+#endif

+

+

+/*

+ * Perform the forward DCT on one block of samples.

+ */

+

+GLOBAL void

+jpeg_fdct_islow (DCTELEM * data)

+{

+  INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

+  INT32 tmp10, tmp11, tmp12, tmp13;

+  INT32 z1, z2, z3, z4, z5;

+  DCTELEM *dataptr;

+  int ctr;

+  SHIFT_TEMPS

+

+  /* Pass 1: process rows. */

+  /* Note results are scaled up by sqrt(8) compared to a true DCT; */

+  /* furthermore, we scale the results by 2**PASS1_BITS. */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[0] + dataptr[7];

+    tmp7 = dataptr[0] - dataptr[7];

+    tmp1 = dataptr[1] + dataptr[6];

+    tmp6 = dataptr[1] - dataptr[6];

+    tmp2 = dataptr[2] + dataptr[5];

+    tmp5 = dataptr[2] - dataptr[5];

+    tmp3 = dataptr[3] + dataptr[4];

+    tmp4 = dataptr[3] - dataptr[4];

+    

+    /* Even part per LL&M figure 1 --- note that published figure is faulty;

+     * rotator "sqrt(2)*c1" should be "sqrt(2)*c6".

+     */

+    

+    tmp10 = tmp0 + tmp3;

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[0] = (DCTELEM) ((tmp10 + tmp11) << PASS1_BITS);

+    dataptr[4] = (DCTELEM) ((tmp10 - tmp11) << PASS1_BITS);

+    

+    z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);

+    dataptr[2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),

+				   CONST_BITS-PASS1_BITS);

+    dataptr[6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),

+				   CONST_BITS-PASS1_BITS);

+    

+    /* Odd part per figure 8 --- note paper omits factor of sqrt(2).

+     * cK represents cos(K*pi/16).

+     * i0..i3 in the paper are tmp4..tmp7 here.

+     */

+    

+    z1 = tmp4 + tmp7;

+    z2 = tmp5 + tmp6;

+    z3 = tmp4 + tmp6;

+    z4 = tmp5 + tmp7;

+    z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */

+    

+    tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */

+    tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */

+    tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */

+    tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */

+    z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */

+    z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */

+    z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */

+    z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */

+    

+    z3 += z5;

+    z4 += z5;

+    

+    dataptr[7] = (DCTELEM) DESCALE(tmp4 + z1 + z3, CONST_BITS-PASS1_BITS);

+    dataptr[5] = (DCTELEM) DESCALE(tmp5 + z2 + z4, CONST_BITS-PASS1_BITS);

+    dataptr[3] = (DCTELEM) DESCALE(tmp6 + z2 + z3, CONST_BITS-PASS1_BITS);

+    dataptr[1] = (DCTELEM) DESCALE(tmp7 + z1 + z4, CONST_BITS-PASS1_BITS);

+    

+    dataptr += DCTSIZE;		/* advance pointer to next row */

+  }

+

+  /* Pass 2: process columns.

+   * We remove the PASS1_BITS scaling, but leave the results scaled up

+   * by an overall factor of 8.

+   */

+

+  dataptr = data;

+  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {

+    tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];

+    tmp7 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];

+    tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];

+    tmp6 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];

+    tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];

+    tmp5 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];

+    tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];

+    tmp4 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];

+    

+    /* Even part per LL&M figure 1 --- note that published figure is faulty;

+     * rotator "sqrt(2)*c1" should be "sqrt(2)*c6".

+     */

+    

+    tmp10 = tmp0 + tmp3;

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp11, PASS1_BITS);

+    dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp10 - tmp11, PASS1_BITS);

+    

+    z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100);

+    dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp13, FIX_0_765366865),

+					   CONST_BITS+PASS1_BITS);

+    dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 + MULTIPLY(tmp12, - FIX_1_847759065),

+					   CONST_BITS+PASS1_BITS);

+    

+    /* Odd part per figure 8 --- note paper omits factor of sqrt(2).

+     * cK represents cos(K*pi/16).

+     * i0..i3 in the paper are tmp4..tmp7 here.

+     */

+    

+    z1 = tmp4 + tmp7;

+    z2 = tmp5 + tmp6;

+    z3 = tmp4 + tmp6;

+    z4 = tmp5 + tmp7;

+    z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */

+    

+    tmp4 = MULTIPLY(tmp4, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */

+    tmp5 = MULTIPLY(tmp5, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */

+    tmp6 = MULTIPLY(tmp6, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */

+    tmp7 = MULTIPLY(tmp7, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */

+    z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */

+    z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */

+    z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */

+    z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */

+    

+    z3 += z5;

+    z4 += z5;

+    

+    dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp4 + z1 + z3,

+					   CONST_BITS+PASS1_BITS);

+    dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp5 + z2 + z4,

+					   CONST_BITS+PASS1_BITS);

+    dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp6 + z2 + z3,

+					   CONST_BITS+PASS1_BITS);

+    dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp7 + z1 + z4,

+					   CONST_BITS+PASS1_BITS);

+    

+    dataptr++;			/* advance pointer to next column */

+  }

+}

+

+#endif /* DCT_ISLOW_SUPPORTED */

diff --git a/code/jpeg-6/jidctflt.c b/code/jpeg-6/jidctflt.c
new file mode 100755
index 0000000..2e25c44
--- /dev/null
+++ b/code/jpeg-6/jidctflt.c
@@ -0,0 +1,241 @@
+/*

+ * jidctflt.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a floating-point implementation of the

+ * inverse DCT (Discrete Cosine Transform).  In the IJG code, this routine

+ * must also perform dequantization of the input coefficients.

+ *

+ * This implementation should be more accurate than either of the integer

+ * IDCT implementations.  However, it may not give the same results on all

+ * machines because of differences in roundoff behavior.  Speed will depend

+ * on the hardware's floating point capacity.

+ *

+ * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT

+ * on each row (or vice versa, but it's more convenient to emit a row at

+ * a time).  Direct algorithms are also available, but they are much more

+ * complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on Arai, Agui, and Nakajima's algorithm for

+ * scaled DCT.  Their original paper (Trans. IEICE E-71(11):1095) is in

+ * Japanese, but the algorithm is described in the Pennebaker & Mitchell

+ * JPEG textbook (see REFERENCES section in file README).  The following code

+ * is based directly on figure 4-8 in P&M.

+ * While an 8-point DCT cannot be done in less than 11 multiplies, it is

+ * possible to arrange the computation so that many of the multiplies are

+ * simple scalings of the final outputs.  These multiplies can then be

+ * folded into the multiplications or divisions by the JPEG quantization

+ * table entries.  The AA&N method leaves only 5 multiplies and 29 adds

+ * to be done in the DCT itself.

+ * The primary disadvantage of this method is that with a fixed-point

+ * implementation, accuracy is lost due to imprecise representation of the

+ * scaled quantization values.  However, that problem does not arise if

+ * we use floating point arithmetic.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_FLOAT_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/* Dequantize a coefficient by multiplying it by the multiplier-table

+ * entry; produce a float result.

+ */

+

+#define DEQUANTIZE(coef,quantval)  (((FAST_FLOAT) (coef)) * (quantval))

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients.

+ */

+

+GLOBAL void

+jpeg_idct_float (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		 JCOEFPTR coef_block,

+		 JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  FAST_FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

+  FAST_FLOAT tmp10, tmp11, tmp12, tmp13;

+  FAST_FLOAT z5, z10, z11, z12, z13;

+  JCOEFPTR inptr;

+  FLOAT_MULT_TYPE * quantptr;

+  FAST_FLOAT * wsptr;

+  JSAMPROW outptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  int ctr;

+  FAST_FLOAT workspace[DCTSIZE2]; /* buffers data between passes */

+  SHIFT_TEMPS

+

+  /* Pass 1: process columns from input, store into work array. */

+

+  inptr = coef_block;

+  quantptr = (FLOAT_MULT_TYPE *) compptr->dct_table;

+  wsptr = workspace;

+  for (ctr = DCTSIZE; ctr > 0; ctr--) {

+    /* Due to quantization, we will usually find that many of the input

+     * coefficients are zero, especially the AC terms.  We can exploit this

+     * by short-circuiting the IDCT calculation for any column in which all

+     * the AC terms are zero.  In that case each output is equal to the

+     * DC coefficient (with scale factor as needed).

+     * With typical images and quantization tables, half or more of the

+     * column DCT calculations can be simplified this way.

+     */

+    

+    if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |

+	 inptr[DCTSIZE*4] | inptr[DCTSIZE*5] | inptr[DCTSIZE*6] |

+	 inptr[DCTSIZE*7]) == 0) {

+      /* AC terms all zero */

+      FAST_FLOAT dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+      

+      wsptr[DCTSIZE*0] = dcval;

+      wsptr[DCTSIZE*1] = dcval;

+      wsptr[DCTSIZE*2] = dcval;

+      wsptr[DCTSIZE*3] = dcval;

+      wsptr[DCTSIZE*4] = dcval;

+      wsptr[DCTSIZE*5] = dcval;

+      wsptr[DCTSIZE*6] = dcval;

+      wsptr[DCTSIZE*7] = dcval;

+      

+      inptr++;			/* advance pointers to next column */

+      quantptr++;

+      wsptr++;

+      continue;

+    }

+    

+    /* Even part */

+

+    tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+    tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);

+    tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);

+    tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);

+

+    tmp10 = tmp0 + tmp2;	/* phase 3 */

+    tmp11 = tmp0 - tmp2;

+

+    tmp13 = tmp1 + tmp3;	/* phases 5-3 */

+    tmp12 = (tmp1 - tmp3) * ((FAST_FLOAT) 1.414213562) - tmp13; /* 2*c4 */

+

+    tmp0 = tmp10 + tmp13;	/* phase 2 */

+    tmp3 = tmp10 - tmp13;

+    tmp1 = tmp11 + tmp12;

+    tmp2 = tmp11 - tmp12;

+    

+    /* Odd part */

+

+    tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);

+    tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);

+    tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);

+    tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);

+

+    z13 = tmp6 + tmp5;		/* phase 6 */

+    z10 = tmp6 - tmp5;

+    z11 = tmp4 + tmp7;

+    z12 = tmp4 - tmp7;

+

+    tmp7 = z11 + z13;		/* phase 5 */

+    tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562); /* 2*c4 */

+

+    z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */

+    tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */

+    tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */

+

+    tmp6 = tmp12 - tmp7;	/* phase 2 */

+    tmp5 = tmp11 - tmp6;

+    tmp4 = tmp10 + tmp5;

+

+    wsptr[DCTSIZE*0] = tmp0 + tmp7;

+    wsptr[DCTSIZE*7] = tmp0 - tmp7;

+    wsptr[DCTSIZE*1] = tmp1 + tmp6;

+    wsptr[DCTSIZE*6] = tmp1 - tmp6;

+    wsptr[DCTSIZE*2] = tmp2 + tmp5;

+    wsptr[DCTSIZE*5] = tmp2 - tmp5;

+    wsptr[DCTSIZE*4] = tmp3 + tmp4;

+    wsptr[DCTSIZE*3] = tmp3 - tmp4;

+

+    inptr++;			/* advance pointers to next column */

+    quantptr++;

+    wsptr++;

+  }

+  

+  /* Pass 2: process rows from work array, store into output array. */

+  /* Note that we must descale the results by a factor of 8 == 2**3. */

+

+  wsptr = workspace;

+  for (ctr = 0; ctr < DCTSIZE; ctr++) {

+    outptr = output_buf[ctr] + output_col;

+    /* Rows of zeroes can be exploited in the same way as we did with columns.

+     * However, the column calculation has created many nonzero AC terms, so

+     * the simplification applies less often (typically 5% to 10% of the time).

+     * And testing floats for zero is relatively expensive, so we don't bother.

+     */

+    

+    /* Even part */

+

+    tmp10 = wsptr[0] + wsptr[4];

+    tmp11 = wsptr[0] - wsptr[4];

+

+    tmp13 = wsptr[2] + wsptr[6];

+    tmp12 = (wsptr[2] - wsptr[6]) * ((FAST_FLOAT) 1.414213562) - tmp13;

+

+    tmp0 = tmp10 + tmp13;

+    tmp3 = tmp10 - tmp13;

+    tmp1 = tmp11 + tmp12;

+    tmp2 = tmp11 - tmp12;

+

+    /* Odd part */

+

+    z13 = wsptr[5] + wsptr[3];

+    z10 = wsptr[5] - wsptr[3];

+    z11 = wsptr[1] + wsptr[7];

+    z12 = wsptr[1] - wsptr[7];

+

+    tmp7 = z11 + z13;

+    tmp11 = (z11 - z13) * ((FAST_FLOAT) 1.414213562);

+

+    z5 = (z10 + z12) * ((FAST_FLOAT) 1.847759065); /* 2*c2 */

+    tmp10 = ((FAST_FLOAT) 1.082392200) * z12 - z5; /* 2*(c2-c6) */

+    tmp12 = ((FAST_FLOAT) -2.613125930) * z10 + z5; /* -2*(c2+c6) */

+

+    tmp6 = tmp12 - tmp7;

+    tmp5 = tmp11 - tmp6;

+    tmp4 = tmp10 + tmp5;

+

+    /* Final output stage: scale down by a factor of 8 and range-limit */

+

+    outptr[0] = range_limit[(int) DESCALE((INT32) (tmp0 + tmp7), 3)

+			    & RANGE_MASK];

+    outptr[7] = range_limit[(int) DESCALE((INT32) (tmp0 - tmp7), 3)

+			    & RANGE_MASK];

+    outptr[1] = range_limit[(int) DESCALE((INT32) (tmp1 + tmp6), 3)

+			    & RANGE_MASK];

+    outptr[6] = range_limit[(int) DESCALE((INT32) (tmp1 - tmp6), 3)

+			    & RANGE_MASK];

+    outptr[2] = range_limit[(int) DESCALE((INT32) (tmp2 + tmp5), 3)

+			    & RANGE_MASK];

+    outptr[5] = range_limit[(int) DESCALE((INT32) (tmp2 - tmp5), 3)

+			    & RANGE_MASK];

+    outptr[4] = range_limit[(int) DESCALE((INT32) (tmp3 + tmp4), 3)

+			    & RANGE_MASK];

+    outptr[3] = range_limit[(int) DESCALE((INT32) (tmp3 - tmp4), 3)

+			    & RANGE_MASK];

+    

+    wsptr += DCTSIZE;		/* advance pointer to next row */

+  }

+}

+

+#endif /* DCT_FLOAT_SUPPORTED */

diff --git a/code/jpeg-6/jidctfst.c b/code/jpeg-6/jidctfst.c
new file mode 100755
index 0000000..c9777c5
--- /dev/null
+++ b/code/jpeg-6/jidctfst.c
@@ -0,0 +1,367 @@
+/*

+ * jidctfst.c

+ *

+ * Copyright (C) 1994-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a fast, not so accurate integer implementation of the

+ * inverse DCT (Discrete Cosine Transform).  In the IJG code, this routine

+ * must also perform dequantization of the input coefficients.

+ *

+ * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT

+ * on each row (or vice versa, but it's more convenient to emit a row at

+ * a time).  Direct algorithms are also available, but they are much more

+ * complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on Arai, Agui, and Nakajima's algorithm for

+ * scaled DCT.  Their original paper (Trans. IEICE E-71(11):1095) is in

+ * Japanese, but the algorithm is described in the Pennebaker & Mitchell

+ * JPEG textbook (see REFERENCES section in file README).  The following code

+ * is based directly on figure 4-8 in P&M.

+ * While an 8-point DCT cannot be done in less than 11 multiplies, it is

+ * possible to arrange the computation so that many of the multiplies are

+ * simple scalings of the final outputs.  These multiplies can then be

+ * folded into the multiplications or divisions by the JPEG quantization

+ * table entries.  The AA&N method leaves only 5 multiplies and 29 adds

+ * to be done in the DCT itself.

+ * The primary disadvantage of this method is that with fixed-point math,

+ * accuracy is lost due to imprecise representation of the scaled

+ * quantization values.  The smaller the quantization table entry, the less

+ * precise the scaled value, so this implementation does worse with high-

+ * quality-setting files than with low-quality ones.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_IFAST_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/* Scaling decisions are generally the same as in the LL&M algorithm;

+ * see jidctint.c for more details.  However, we choose to descale

+ * (right shift) multiplication products as soon as they are formed,

+ * rather than carrying additional fractional bits into subsequent additions.

+ * This compromises accuracy slightly, but it lets us save a few shifts.

+ * More importantly, 16-bit arithmetic is then adequate (for 8-bit samples)

+ * everywhere except in the multiplications proper; this saves a good deal

+ * of work on 16-bit-int machines.

+ *

+ * The dequantized coefficients are not integers because the AA&N scaling

+ * factors have been incorporated.  We represent them scaled up by PASS1_BITS,

+ * so that the first and second IDCT rounds have the same input scaling.

+ * For 8-bit JSAMPLEs, we choose IFAST_SCALE_BITS = PASS1_BITS so as to

+ * avoid a descaling shift; this compromises accuracy rather drastically

+ * for small quantization table entries, but it saves a lot of shifts.

+ * For 12-bit JSAMPLEs, there's no hope of using 16x16 multiplies anyway,

+ * so we use a much larger scaling factor to preserve accuracy.

+ *

+ * A final compromise is to represent the multiplicative constants to only

+ * 8 fractional bits, rather than 13.  This saves some shifting work on some

+ * machines, and may also reduce the cost of multiplication (since there

+ * are fewer one-bits in the constants).

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define CONST_BITS  8

+#define PASS1_BITS  2

+#else

+#define CONST_BITS  8

+#define PASS1_BITS  1		/* lose a little precision to avoid overflow */

+#endif

+

+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus

+ * causing a lot of useless floating-point operations at run time.

+ * To get around this we use the following pre-calculated constants.

+ * If you change CONST_BITS you may want to add appropriate values.

+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)

+ */

+

+#if CONST_BITS == 8

+#define FIX_1_082392200  ((INT32)  277)		/* FIX(1.082392200) */

+#define FIX_1_414213562  ((INT32)  362)		/* FIX(1.414213562) */

+#define FIX_1_847759065  ((INT32)  473)		/* FIX(1.847759065) */

+#define FIX_2_613125930  ((INT32)  669)		/* FIX(2.613125930) */

+#else

+#define FIX_1_082392200  FIX(1.082392200)

+#define FIX_1_414213562  FIX(1.414213562)

+#define FIX_1_847759065  FIX(1.847759065)

+#define FIX_2_613125930  FIX(2.613125930)

+#endif

+

+

+/* We can gain a little more speed, with a further compromise in accuracy,

+ * by omitting the addition in a descaling shift.  This yields an incorrectly

+ * rounded result half the time...

+ */

+

+#ifndef USE_ACCURATE_ROUNDING

+#undef DESCALE

+#define DESCALE(x,n)  RIGHT_SHIFT(x, n)

+#endif

+

+

+/* Multiply a DCTELEM variable by an INT32 constant, and immediately

+ * descale to yield a DCTELEM result.

+ */

+

+#define MULTIPLY(var,const)  ((DCTELEM) DESCALE((var) * (const), CONST_BITS))

+

+

+/* Dequantize a coefficient by multiplying it by the multiplier-table

+ * entry; produce a DCTELEM result.  For 8-bit data a 16x16->16

+ * multiplication will do.  For 12-bit data, the multiplier table is

+ * declared INT32, so a 32-bit multiply will be used.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define DEQUANTIZE(coef,quantval)  (((IFAST_MULT_TYPE) (coef)) * (quantval))

+#else

+#define DEQUANTIZE(coef,quantval)  \

+	DESCALE((coef)*(quantval), IFAST_SCALE_BITS-PASS1_BITS)

+#endif

+

+

+/* Like DESCALE, but applies to a DCTELEM and produces an int.

+ * We assume that int right shift is unsigned if INT32 right shift is.

+ */

+

+#ifdef RIGHT_SHIFT_IS_UNSIGNED

+#define ISHIFT_TEMPS	DCTELEM ishift_temp;

+#if BITS_IN_JSAMPLE == 8

+#define DCTELEMBITS  16		/* DCTELEM may be 16 or 32 bits */

+#else

+#define DCTELEMBITS  32		/* DCTELEM must be 32 bits */

+#endif

+#define IRIGHT_SHIFT(x,shft)  \

+    ((ishift_temp = (x)) < 0 ? \

+     (ishift_temp >> (shft)) | ((~((DCTELEM) 0)) << (DCTELEMBITS-(shft))) : \

+     (ishift_temp >> (shft)))

+#else

+#define ISHIFT_TEMPS

+#define IRIGHT_SHIFT(x,shft)	((x) >> (shft))

+#endif

+

+#ifdef USE_ACCURATE_ROUNDING

+#define IDESCALE(x,n)  ((int) IRIGHT_SHIFT((x) + (1 << ((n)-1)), n))

+#else

+#define IDESCALE(x,n)  ((int) IRIGHT_SHIFT(x, n))

+#endif

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients.

+ */

+

+GLOBAL void

+jpeg_idct_ifast (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		 JCOEFPTR coef_block,

+		 JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  DCTELEM tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

+  DCTELEM tmp10, tmp11, tmp12, tmp13;

+  DCTELEM z5, z10, z11, z12, z13;

+  JCOEFPTR inptr;

+  IFAST_MULT_TYPE * quantptr;

+  int * wsptr;

+  JSAMPROW outptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  int ctr;

+  int workspace[DCTSIZE2];	/* buffers data between passes */

+  SHIFT_TEMPS			/* for DESCALE */

+  ISHIFT_TEMPS			/* for IDESCALE */

+

+  /* Pass 1: process columns from input, store into work array. */

+

+  inptr = coef_block;

+  quantptr = (IFAST_MULT_TYPE *) compptr->dct_table;

+  wsptr = workspace;

+  for (ctr = DCTSIZE; ctr > 0; ctr--) {

+    /* Due to quantization, we will usually find that many of the input

+     * coefficients are zero, especially the AC terms.  We can exploit this

+     * by short-circuiting the IDCT calculation for any column in which all

+     * the AC terms are zero.  In that case each output is equal to the

+     * DC coefficient (with scale factor as needed).

+     * With typical images and quantization tables, half or more of the

+     * column DCT calculations can be simplified this way.

+     */

+    

+    if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |

+	 inptr[DCTSIZE*4] | inptr[DCTSIZE*5] | inptr[DCTSIZE*6] |

+	 inptr[DCTSIZE*7]) == 0) {

+      /* AC terms all zero */

+      int dcval = (int) DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+

+      wsptr[DCTSIZE*0] = dcval;

+      wsptr[DCTSIZE*1] = dcval;

+      wsptr[DCTSIZE*2] = dcval;

+      wsptr[DCTSIZE*3] = dcval;

+      wsptr[DCTSIZE*4] = dcval;

+      wsptr[DCTSIZE*5] = dcval;

+      wsptr[DCTSIZE*6] = dcval;

+      wsptr[DCTSIZE*7] = dcval;

+      

+      inptr++;			/* advance pointers to next column */

+      quantptr++;

+      wsptr++;

+      continue;

+    }

+    

+    /* Even part */

+

+    tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+    tmp1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);

+    tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);

+    tmp3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);

+

+    tmp10 = tmp0 + tmp2;	/* phase 3 */

+    tmp11 = tmp0 - tmp2;

+

+    tmp13 = tmp1 + tmp3;	/* phases 5-3 */

+    tmp12 = MULTIPLY(tmp1 - tmp3, FIX_1_414213562) - tmp13; /* 2*c4 */

+

+    tmp0 = tmp10 + tmp13;	/* phase 2 */

+    tmp3 = tmp10 - tmp13;

+    tmp1 = tmp11 + tmp12;

+    tmp2 = tmp11 - tmp12;

+    

+    /* Odd part */

+

+    tmp4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);

+    tmp5 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);

+    tmp6 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);

+    tmp7 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);

+

+    z13 = tmp6 + tmp5;		/* phase 6 */

+    z10 = tmp6 - tmp5;

+    z11 = tmp4 + tmp7;

+    z12 = tmp4 - tmp7;

+

+    tmp7 = z11 + z13;		/* phase 5 */

+    tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */

+

+    z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */

+    tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */

+    tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */

+

+    tmp6 = tmp12 - tmp7;	/* phase 2 */

+    tmp5 = tmp11 - tmp6;

+    tmp4 = tmp10 + tmp5;

+

+    wsptr[DCTSIZE*0] = (int) (tmp0 + tmp7);

+    wsptr[DCTSIZE*7] = (int) (tmp0 - tmp7);

+    wsptr[DCTSIZE*1] = (int) (tmp1 + tmp6);

+    wsptr[DCTSIZE*6] = (int) (tmp1 - tmp6);

+    wsptr[DCTSIZE*2] = (int) (tmp2 + tmp5);

+    wsptr[DCTSIZE*5] = (int) (tmp2 - tmp5);

+    wsptr[DCTSIZE*4] = (int) (tmp3 + tmp4);

+    wsptr[DCTSIZE*3] = (int) (tmp3 - tmp4);

+

+    inptr++;			/* advance pointers to next column */

+    quantptr++;

+    wsptr++;

+  }

+  

+  /* Pass 2: process rows from work array, store into output array. */

+  /* Note that we must descale the results by a factor of 8 == 2**3, */

+  /* and also undo the PASS1_BITS scaling. */

+

+  wsptr = workspace;

+  for (ctr = 0; ctr < DCTSIZE; ctr++) {

+    outptr = output_buf[ctr] + output_col;

+    /* Rows of zeroes can be exploited in the same way as we did with columns.

+     * However, the column calculation has created many nonzero AC terms, so

+     * the simplification applies less often (typically 5% to 10% of the time).

+     * On machines with very fast multiplication, it's possible that the

+     * test takes more time than it's worth.  In that case this section

+     * may be commented out.

+     */

+    

+#ifndef NO_ZERO_ROW_TEST

+    if ((wsptr[1] | wsptr[2] | wsptr[3] | wsptr[4] | wsptr[5] | wsptr[6] |

+	 wsptr[7]) == 0) {

+      /* AC terms all zero */

+      JSAMPLE dcval = range_limit[IDESCALE(wsptr[0], PASS1_BITS+3)

+				  & RANGE_MASK];

+      

+      outptr[0] = dcval;

+      outptr[1] = dcval;

+      outptr[2] = dcval;

+      outptr[3] = dcval;

+      outptr[4] = dcval;

+      outptr[5] = dcval;

+      outptr[6] = dcval;

+      outptr[7] = dcval;

+

+      wsptr += DCTSIZE;		/* advance pointer to next row */

+      continue;

+    }

+#endif

+    

+    /* Even part */

+

+    tmp10 = ((DCTELEM) wsptr[0] + (DCTELEM) wsptr[4]);

+    tmp11 = ((DCTELEM) wsptr[0] - (DCTELEM) wsptr[4]);

+

+    tmp13 = ((DCTELEM) wsptr[2] + (DCTELEM) wsptr[6]);

+    tmp12 = MULTIPLY((DCTELEM) wsptr[2] - (DCTELEM) wsptr[6], FIX_1_414213562)

+	    - tmp13;

+

+    tmp0 = tmp10 + tmp13;

+    tmp3 = tmp10 - tmp13;

+    tmp1 = tmp11 + tmp12;

+    tmp2 = tmp11 - tmp12;

+

+    /* Odd part */

+

+    z13 = (DCTELEM) wsptr[5] + (DCTELEM) wsptr[3];

+    z10 = (DCTELEM) wsptr[5] - (DCTELEM) wsptr[3];

+    z11 = (DCTELEM) wsptr[1] + (DCTELEM) wsptr[7];

+    z12 = (DCTELEM) wsptr[1] - (DCTELEM) wsptr[7];

+

+    tmp7 = z11 + z13;		/* phase 5 */

+    tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562); /* 2*c4 */

+

+    z5 = MULTIPLY(z10 + z12, FIX_1_847759065); /* 2*c2 */

+    tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */

+    tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5; /* -2*(c2+c6) */

+

+    tmp6 = tmp12 - tmp7;	/* phase 2 */

+    tmp5 = tmp11 - tmp6;

+    tmp4 = tmp10 + tmp5;

+

+    /* Final output stage: scale down by a factor of 8 and range-limit */

+

+    outptr[0] = range_limit[IDESCALE(tmp0 + tmp7, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[7] = range_limit[IDESCALE(tmp0 - tmp7, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[1] = range_limit[IDESCALE(tmp1 + tmp6, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[6] = range_limit[IDESCALE(tmp1 - tmp6, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[2] = range_limit[IDESCALE(tmp2 + tmp5, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[5] = range_limit[IDESCALE(tmp2 - tmp5, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[4] = range_limit[IDESCALE(tmp3 + tmp4, PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[3] = range_limit[IDESCALE(tmp3 - tmp4, PASS1_BITS+3)

+			    & RANGE_MASK];

+

+    wsptr += DCTSIZE;		/* advance pointer to next row */

+  }

+}

+

+#endif /* DCT_IFAST_SUPPORTED */

diff --git a/code/jpeg-6/jidctint.c b/code/jpeg-6/jidctint.c
new file mode 100755
index 0000000..b3271d8
--- /dev/null
+++ b/code/jpeg-6/jidctint.c
@@ -0,0 +1,388 @@
+/*

+ * jidctint.c

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a slow-but-accurate integer implementation of the

+ * inverse DCT (Discrete Cosine Transform).  In the IJG code, this routine

+ * must also perform dequantization of the input coefficients.

+ *

+ * A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT

+ * on each row (or vice versa, but it's more convenient to emit a row at

+ * a time).  Direct algorithms are also available, but they are much more

+ * complex and seem not to be any faster when reduced to code.

+ *

+ * This implementation is based on an algorithm described in

+ *   C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT

+ *   Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics,

+ *   Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991.

+ * The primary algorithm described there uses 11 multiplies and 29 adds.

+ * We use their alternate method with 12 multiplies and 32 adds.

+ * The advantage of this method is that no data path contains more than one

+ * multiplication; this allows a very simple and accurate implementation in

+ * scaled fixed-point arithmetic, with a minimal number of shifts.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef DCT_ISLOW_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/*

+ * The poop on this scaling stuff is as follows:

+ *

+ * Each 1-D IDCT step produces outputs which are a factor of sqrt(N)

+ * larger than the true IDCT outputs.  The final outputs are therefore

+ * a factor of N larger than desired; since N=8 this can be cured by

+ * a simple right shift at the end of the algorithm.  The advantage of

+ * this arrangement is that we save two multiplications per 1-D IDCT,

+ * because the y0 and y4 inputs need not be divided by sqrt(N).

+ *

+ * We have to do addition and subtraction of the integer inputs, which

+ * is no problem, and multiplication by fractional constants, which is

+ * a problem to do in integer arithmetic.  We multiply all the constants

+ * by CONST_SCALE and convert them to integer constants (thus retaining

+ * CONST_BITS bits of precision in the constants).  After doing a

+ * multiplication we have to divide the product by CONST_SCALE, with proper

+ * rounding, to produce the correct output.  This division can be done

+ * cheaply as a right shift of CONST_BITS bits.  We postpone shifting

+ * as long as possible so that partial sums can be added together with

+ * full fractional precision.

+ *

+ * The outputs of the first pass are scaled up by PASS1_BITS bits so that

+ * they are represented to better-than-integral precision.  These outputs

+ * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word

+ * with the recommended scaling.  (To scale up 12-bit sample data further, an

+ * intermediate INT32 array would be needed.)

+ *

+ * To avoid overflow of the 32-bit intermediate results in pass 2, we must

+ * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26.  Error analysis

+ * shows that the values given below are the most effective.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define CONST_BITS  13

+#define PASS1_BITS  2

+#else

+#define CONST_BITS  13

+#define PASS1_BITS  1		/* lose a little precision to avoid overflow */

+#endif

+

+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus

+ * causing a lot of useless floating-point operations at run time.

+ * To get around this we use the following pre-calculated constants.

+ * If you change CONST_BITS you may want to add appropriate values.

+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)

+ */

+

+#if CONST_BITS == 13

+#define FIX_0_298631336  ((INT32)  2446)	/* FIX(0.298631336) */

+#define FIX_0_390180644  ((INT32)  3196)	/* FIX(0.390180644) */

+#define FIX_0_541196100  ((INT32)  4433)	/* FIX(0.541196100) */

+#define FIX_0_765366865  ((INT32)  6270)	/* FIX(0.765366865) */

+#define FIX_0_899976223  ((INT32)  7373)	/* FIX(0.899976223) */

+#define FIX_1_175875602  ((INT32)  9633)	/* FIX(1.175875602) */

+#define FIX_1_501321110  ((INT32)  12299)	/* FIX(1.501321110) */

+#define FIX_1_847759065  ((INT32)  15137)	/* FIX(1.847759065) */

+#define FIX_1_961570560  ((INT32)  16069)	/* FIX(1.961570560) */

+#define FIX_2_053119869  ((INT32)  16819)	/* FIX(2.053119869) */

+#define FIX_2_562915447  ((INT32)  20995)	/* FIX(2.562915447) */

+#define FIX_3_072711026  ((INT32)  25172)	/* FIX(3.072711026) */

+#else

+#define FIX_0_298631336  FIX(0.298631336)

+#define FIX_0_390180644  FIX(0.390180644)

+#define FIX_0_541196100  FIX(0.541196100)

+#define FIX_0_765366865  FIX(0.765366865)

+#define FIX_0_899976223  FIX(0.899976223)

+#define FIX_1_175875602  FIX(1.175875602)

+#define FIX_1_501321110  FIX(1.501321110)

+#define FIX_1_847759065  FIX(1.847759065)

+#define FIX_1_961570560  FIX(1.961570560)

+#define FIX_2_053119869  FIX(2.053119869)

+#define FIX_2_562915447  FIX(2.562915447)

+#define FIX_3_072711026  FIX(3.072711026)

+#endif

+

+

+/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.

+ * For 8-bit samples with the recommended scaling, all the variable

+ * and constant values involved are no more than 16 bits wide, so a

+ * 16x16->32 bit multiply can be used instead of a full 32x32 multiply.

+ * For 12-bit samples, a full 32-bit multiplication will be needed.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define MULTIPLY(var,const)  MULTIPLY16C16(var,const)

+#else

+#define MULTIPLY(var,const)  ((var) * (const))

+#endif

+

+

+/* Dequantize a coefficient by multiplying it by the multiplier-table

+ * entry; produce an int result.  In this module, both inputs and result

+ * are 16 bits or less, so either int or short multiply will work.

+ */

+

+#define DEQUANTIZE(coef,quantval)  (((ISLOW_MULT_TYPE) (coef)) * (quantval))

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients.

+ */

+

+GLOBAL void

+jpeg_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		 JCOEFPTR coef_block,

+		 JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  INT32 tmp0, tmp1, tmp2, tmp3;

+  INT32 tmp10, tmp11, tmp12, tmp13;

+  INT32 z1, z2, z3, z4, z5;

+  JCOEFPTR inptr;

+  ISLOW_MULT_TYPE * quantptr;

+  int * wsptr;

+  JSAMPROW outptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  int ctr;

+  int workspace[DCTSIZE2];	/* buffers data between passes */

+  SHIFT_TEMPS

+

+  /* Pass 1: process columns from input, store into work array. */

+  /* Note results are scaled up by sqrt(8) compared to a true IDCT; */

+  /* furthermore, we scale the results by 2**PASS1_BITS. */

+

+  inptr = coef_block;

+  quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;

+  wsptr = workspace;

+  for (ctr = DCTSIZE; ctr > 0; ctr--) {

+    /* Due to quantization, we will usually find that many of the input

+     * coefficients are zero, especially the AC terms.  We can exploit this

+     * by short-circuiting the IDCT calculation for any column in which all

+     * the AC terms are zero.  In that case each output is equal to the

+     * DC coefficient (with scale factor as needed).

+     * With typical images and quantization tables, half or more of the

+     * column DCT calculations can be simplified this way.

+     */

+    

+    if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |

+	 inptr[DCTSIZE*4] | inptr[DCTSIZE*5] | inptr[DCTSIZE*6] |

+	 inptr[DCTSIZE*7]) == 0) {

+      /* AC terms all zero */

+      int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;

+      

+      wsptr[DCTSIZE*0] = dcval;

+      wsptr[DCTSIZE*1] = dcval;

+      wsptr[DCTSIZE*2] = dcval;

+      wsptr[DCTSIZE*3] = dcval;

+      wsptr[DCTSIZE*4] = dcval;

+      wsptr[DCTSIZE*5] = dcval;

+      wsptr[DCTSIZE*6] = dcval;

+      wsptr[DCTSIZE*7] = dcval;

+      

+      inptr++;			/* advance pointers to next column */

+      quantptr++;

+      wsptr++;

+      continue;

+    }

+    

+    /* Even part: reverse the even part of the forward DCT. */

+    /* The rotator is sqrt(2)*c(-6). */

+    

+    z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);

+    z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);

+    

+    z1 = MULTIPLY(z2 + z3, FIX_0_541196100);

+    tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065);

+    tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865);

+    

+    z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+    z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);

+

+    tmp0 = (z2 + z3) << CONST_BITS;

+    tmp1 = (z2 - z3) << CONST_BITS;

+    

+    tmp10 = tmp0 + tmp3;

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    /* Odd part per figure 8; the matrix is unitary and hence its

+     * transpose is its inverse.  i0..i3 are y7,y5,y3,y1 respectively.

+     */

+    

+    tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);

+    tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);

+    tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);

+    tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);

+    

+    z1 = tmp0 + tmp3;

+    z2 = tmp1 + tmp2;

+    z3 = tmp0 + tmp2;

+    z4 = tmp1 + tmp3;

+    z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */

+    

+    tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */

+    tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */

+    tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */

+    tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */

+    z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */

+    z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */

+    z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */

+    z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */

+    

+    z3 += z5;

+    z4 += z5;

+    

+    tmp0 += z1 + z3;

+    tmp1 += z2 + z4;

+    tmp2 += z2 + z3;

+    tmp3 += z1 + z4;

+    

+    /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */

+    

+    wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp3, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*7] = (int) DESCALE(tmp10 - tmp3, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*1] = (int) DESCALE(tmp11 + tmp2, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*6] = (int) DESCALE(tmp11 - tmp2, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*2] = (int) DESCALE(tmp12 + tmp1, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*5] = (int) DESCALE(tmp12 - tmp1, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*3] = (int) DESCALE(tmp13 + tmp0, CONST_BITS-PASS1_BITS);

+    wsptr[DCTSIZE*4] = (int) DESCALE(tmp13 - tmp0, CONST_BITS-PASS1_BITS);

+    

+    inptr++;			/* advance pointers to next column */

+    quantptr++;

+    wsptr++;

+  }

+  

+  /* Pass 2: process rows from work array, store into output array. */

+  /* Note that we must descale the results by a factor of 8 == 2**3, */

+  /* and also undo the PASS1_BITS scaling. */

+

+  wsptr = workspace;

+  for (ctr = 0; ctr < DCTSIZE; ctr++) {

+    outptr = output_buf[ctr] + output_col;

+    /* Rows of zeroes can be exploited in the same way as we did with columns.

+     * However, the column calculation has created many nonzero AC terms, so

+     * the simplification applies less often (typically 5% to 10% of the time).

+     * On machines with very fast multiplication, it's possible that the

+     * test takes more time than it's worth.  In that case this section

+     * may be commented out.

+     */

+    

+#ifndef NO_ZERO_ROW_TEST

+    if ((wsptr[1] | wsptr[2] | wsptr[3] | wsptr[4] | wsptr[5] | wsptr[6] |

+	 wsptr[7]) == 0) {

+      /* AC terms all zero */

+      JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3)

+				  & RANGE_MASK];

+      

+      outptr[0] = dcval;

+      outptr[1] = dcval;

+      outptr[2] = dcval;

+      outptr[3] = dcval;

+      outptr[4] = dcval;

+      outptr[5] = dcval;

+      outptr[6] = dcval;

+      outptr[7] = dcval;

+

+      wsptr += DCTSIZE;		/* advance pointer to next row */

+      continue;

+    }

+#endif

+    

+    /* Even part: reverse the even part of the forward DCT. */

+    /* The rotator is sqrt(2)*c(-6). */

+    

+    z2 = (INT32) wsptr[2];

+    z3 = (INT32) wsptr[6];

+    

+    z1 = MULTIPLY(z2 + z3, FIX_0_541196100);

+    tmp2 = z1 + MULTIPLY(z3, - FIX_1_847759065);

+    tmp3 = z1 + MULTIPLY(z2, FIX_0_765366865);

+    

+    tmp0 = ((INT32) wsptr[0] + (INT32) wsptr[4]) << CONST_BITS;

+    tmp1 = ((INT32) wsptr[0] - (INT32) wsptr[4]) << CONST_BITS;

+    

+    tmp10 = tmp0 + tmp3;

+    tmp13 = tmp0 - tmp3;

+    tmp11 = tmp1 + tmp2;

+    tmp12 = tmp1 - tmp2;

+    

+    /* Odd part per figure 8; the matrix is unitary and hence its

+     * transpose is its inverse.  i0..i3 are y7,y5,y3,y1 respectively.

+     */

+    

+    tmp0 = (INT32) wsptr[7];

+    tmp1 = (INT32) wsptr[5];

+    tmp2 = (INT32) wsptr[3];

+    tmp3 = (INT32) wsptr[1];

+    

+    z1 = tmp0 + tmp3;

+    z2 = tmp1 + tmp2;

+    z3 = tmp0 + tmp2;

+    z4 = tmp1 + tmp3;

+    z5 = MULTIPLY(z3 + z4, FIX_1_175875602); /* sqrt(2) * c3 */

+    

+    tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */

+    tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */

+    tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */

+    tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */

+    z1 = MULTIPLY(z1, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */

+    z2 = MULTIPLY(z2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */

+    z3 = MULTIPLY(z3, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */

+    z4 = MULTIPLY(z4, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */

+    

+    z3 += z5;

+    z4 += z5;

+    

+    tmp0 += z1 + z3;

+    tmp1 += z2 + z4;

+    tmp2 += z2 + z3;

+    tmp3 += z1 + z4;

+    

+    /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */

+    

+    outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp3,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[7] = range_limit[(int) DESCALE(tmp10 - tmp3,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[1] = range_limit[(int) DESCALE(tmp11 + tmp2,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[6] = range_limit[(int) DESCALE(tmp11 - tmp2,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[2] = range_limit[(int) DESCALE(tmp12 + tmp1,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[5] = range_limit[(int) DESCALE(tmp12 - tmp1,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[3] = range_limit[(int) DESCALE(tmp13 + tmp0,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    outptr[4] = range_limit[(int) DESCALE(tmp13 - tmp0,

+					  CONST_BITS+PASS1_BITS+3)

+			    & RANGE_MASK];

+    

+    wsptr += DCTSIZE;		/* advance pointer to next row */

+  }

+}

+

+#endif /* DCT_ISLOW_SUPPORTED */

diff --git a/code/jpeg-6/jidctred.c b/code/jpeg-6/jidctred.c
new file mode 100755
index 0000000..13877ed
--- /dev/null
+++ b/code/jpeg-6/jidctred.c
@@ -0,0 +1,397 @@
+/*

+ * jidctred.c

+ *

+ * Copyright (C) 1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains inverse-DCT routines that produce reduced-size output:

+ * either 4x4, 2x2, or 1x1 pixels from an 8x8 DCT block.

+ *

+ * The implementation is based on the Loeffler, Ligtenberg and Moschytz (LL&M)

+ * algorithm used in jidctint.c.  We simply replace each 8-to-8 1-D IDCT step

+ * with an 8-to-4 step that produces the four averages of two adjacent outputs

+ * (or an 8-to-2 step producing two averages of four outputs, for 2x2 output).

+ * These steps were derived by computing the corresponding values at the end

+ * of the normal LL&M code, then simplifying as much as possible.

+ *

+ * 1x1 is trivial: just take the DC coefficient divided by 8.

+ *

+ * See jidctint.c for additional comments.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jdct.h"		/* Private declarations for DCT subsystem */

+

+#ifdef IDCT_SCALING_SUPPORTED

+

+

+/*

+ * This module is specialized to the case DCTSIZE = 8.

+ */

+

+#if DCTSIZE != 8

+  Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */

+#endif

+

+

+/* Scaling is the same as in jidctint.c. */

+

+#if BITS_IN_JSAMPLE == 8

+#define CONST_BITS  13

+#define PASS1_BITS  2

+#else

+#define CONST_BITS  13

+#define PASS1_BITS  1		/* lose a little precision to avoid overflow */

+#endif

+

+/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus

+ * causing a lot of useless floating-point operations at run time.

+ * To get around this we use the following pre-calculated constants.

+ * If you change CONST_BITS you may want to add appropriate values.

+ * (With a reasonable C compiler, you can just rely on the FIX() macro...)

+ */

+

+#if CONST_BITS == 13

+#define FIX_0_211164243  ((INT32)  1730)	/* FIX(0.211164243) */

+#define FIX_0_509795579  ((INT32)  4176)	/* FIX(0.509795579) */

+#define FIX_0_601344887  ((INT32)  4926)	/* FIX(0.601344887) */

+#define FIX_0_720959822  ((INT32)  5906)	/* FIX(0.720959822) */

+#define FIX_0_765366865  ((INT32)  6270)	/* FIX(0.765366865) */

+#define FIX_0_850430095  ((INT32)  6967)	/* FIX(0.850430095) */

+#define FIX_0_899976223  ((INT32)  7373)	/* FIX(0.899976223) */

+#define FIX_1_061594337  ((INT32)  8697)	/* FIX(1.061594337) */

+#define FIX_1_272758580  ((INT32)  10426)	/* FIX(1.272758580) */

+#define FIX_1_451774981  ((INT32)  11893)	/* FIX(1.451774981) */

+#define FIX_1_847759065  ((INT32)  15137)	/* FIX(1.847759065) */

+#define FIX_2_172734803  ((INT32)  17799)	/* FIX(2.172734803) */

+#define FIX_2_562915447  ((INT32)  20995)	/* FIX(2.562915447) */

+#define FIX_3_624509785  ((INT32)  29692)	/* FIX(3.624509785) */

+#else

+#define FIX_0_211164243  FIX(0.211164243)

+#define FIX_0_509795579  FIX(0.509795579)

+#define FIX_0_601344887  FIX(0.601344887)

+#define FIX_0_720959822  FIX(0.720959822)

+#define FIX_0_765366865  FIX(0.765366865)

+#define FIX_0_850430095  FIX(0.850430095)

+#define FIX_0_899976223  FIX(0.899976223)

+#define FIX_1_061594337  FIX(1.061594337)

+#define FIX_1_272758580  FIX(1.272758580)

+#define FIX_1_451774981  FIX(1.451774981)

+#define FIX_1_847759065  FIX(1.847759065)

+#define FIX_2_172734803  FIX(2.172734803)

+#define FIX_2_562915447  FIX(2.562915447)

+#define FIX_3_624509785  FIX(3.624509785)

+#endif

+

+

+/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.

+ * For 8-bit samples with the recommended scaling, all the variable

+ * and constant values involved are no more than 16 bits wide, so a

+ * 16x16->32 bit multiply can be used instead of a full 32x32 multiply.

+ * For 12-bit samples, a full 32-bit multiplication will be needed.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+#define MULTIPLY(var,const)  MULTIPLY16C16(var,const)

+#else

+#define MULTIPLY(var,const)  ((var) * (const))

+#endif

+

+

+/* Dequantize a coefficient by multiplying it by the multiplier-table

+ * entry; produce an int result.  In this module, both inputs and result

+ * are 16 bits or less, so either int or short multiply will work.

+ */

+

+#define DEQUANTIZE(coef,quantval)  (((ISLOW_MULT_TYPE) (coef)) * (quantval))

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients,

+ * producing a reduced-size 4x4 output block.

+ */

+

+GLOBAL void

+jpeg_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JCOEFPTR coef_block,

+	       JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  INT32 tmp0, tmp2, tmp10, tmp12;

+  INT32 z1, z2, z3, z4;

+  JCOEFPTR inptr;

+  ISLOW_MULT_TYPE * quantptr;

+  int * wsptr;

+  JSAMPROW outptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  int ctr;

+  int workspace[DCTSIZE*4];	/* buffers data between passes */

+  SHIFT_TEMPS

+

+  /* Pass 1: process columns from input, store into work array. */

+

+  inptr = coef_block;

+  quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;

+  wsptr = workspace;

+  for (ctr = DCTSIZE; ctr > 0; inptr++, quantptr++, wsptr++, ctr--) {

+    /* Don't bother to process column 4, because second pass won't use it */

+    if (ctr == DCTSIZE-4)

+      continue;

+    if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*2] | inptr[DCTSIZE*3] |

+	 inptr[DCTSIZE*5] | inptr[DCTSIZE*6] | inptr[DCTSIZE*7]) == 0) {

+      /* AC terms all zero; we need not examine term 4 for 4x4 output */

+      int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;

+      

+      wsptr[DCTSIZE*0] = dcval;

+      wsptr[DCTSIZE*1] = dcval;

+      wsptr[DCTSIZE*2] = dcval;

+      wsptr[DCTSIZE*3] = dcval;

+      

+      continue;

+    }

+    

+    /* Even part */

+    

+    tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+    tmp0 <<= (CONST_BITS+1);

+    

+    z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);

+    z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);

+

+    tmp2 = MULTIPLY(z2, FIX_1_847759065) + MULTIPLY(z3, - FIX_0_765366865);

+    

+    tmp10 = tmp0 + tmp2;

+    tmp12 = tmp0 - tmp2;

+    

+    /* Odd part */

+    

+    z1 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);

+    z2 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);

+    z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);

+    z4 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);

+    

+    tmp0 = MULTIPLY(z1, - FIX_0_211164243) /* sqrt(2) * (c3-c1) */

+	 + MULTIPLY(z2, FIX_1_451774981) /* sqrt(2) * (c3+c7) */

+	 + MULTIPLY(z3, - FIX_2_172734803) /* sqrt(2) * (-c1-c5) */

+	 + MULTIPLY(z4, FIX_1_061594337); /* sqrt(2) * (c5+c7) */

+    

+    tmp2 = MULTIPLY(z1, - FIX_0_509795579) /* sqrt(2) * (c7-c5) */

+	 + MULTIPLY(z2, - FIX_0_601344887) /* sqrt(2) * (c5-c1) */

+	 + MULTIPLY(z3, FIX_0_899976223) /* sqrt(2) * (c3-c7) */

+	 + MULTIPLY(z4, FIX_2_562915447); /* sqrt(2) * (c1+c3) */

+

+    /* Final output stage */

+    

+    wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp2, CONST_BITS-PASS1_BITS+1);

+    wsptr[DCTSIZE*3] = (int) DESCALE(tmp10 - tmp2, CONST_BITS-PASS1_BITS+1);

+    wsptr[DCTSIZE*1] = (int) DESCALE(tmp12 + tmp0, CONST_BITS-PASS1_BITS+1);

+    wsptr[DCTSIZE*2] = (int) DESCALE(tmp12 - tmp0, CONST_BITS-PASS1_BITS+1);

+  }

+  

+  /* Pass 2: process 4 rows from work array, store into output array. */

+

+  wsptr = workspace;

+  for (ctr = 0; ctr < 4; ctr++) {

+    outptr = output_buf[ctr] + output_col;

+    /* It's not clear whether a zero row test is worthwhile here ... */

+

+#ifndef NO_ZERO_ROW_TEST

+    if ((wsptr[1] | wsptr[2] | wsptr[3] | wsptr[5] | wsptr[6] |

+	 wsptr[7]) == 0) {

+      /* AC terms all zero */

+      JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3)

+				  & RANGE_MASK];

+      

+      outptr[0] = dcval;

+      outptr[1] = dcval;

+      outptr[2] = dcval;

+      outptr[3] = dcval;

+      

+      wsptr += DCTSIZE;		/* advance pointer to next row */

+      continue;

+    }

+#endif

+    

+    /* Even part */

+    

+    tmp0 = ((INT32) wsptr[0]) << (CONST_BITS+1);

+    

+    tmp2 = MULTIPLY((INT32) wsptr[2], FIX_1_847759065)

+	 + MULTIPLY((INT32) wsptr[6], - FIX_0_765366865);

+    

+    tmp10 = tmp0 + tmp2;

+    tmp12 = tmp0 - tmp2;

+    

+    /* Odd part */

+    

+    z1 = (INT32) wsptr[7];

+    z2 = (INT32) wsptr[5];

+    z3 = (INT32) wsptr[3];

+    z4 = (INT32) wsptr[1];

+    

+    tmp0 = MULTIPLY(z1, - FIX_0_211164243) /* sqrt(2) * (c3-c1) */

+	 + MULTIPLY(z2, FIX_1_451774981) /* sqrt(2) * (c3+c7) */

+	 + MULTIPLY(z3, - FIX_2_172734803) /* sqrt(2) * (-c1-c5) */

+	 + MULTIPLY(z4, FIX_1_061594337); /* sqrt(2) * (c5+c7) */

+    

+    tmp2 = MULTIPLY(z1, - FIX_0_509795579) /* sqrt(2) * (c7-c5) */

+	 + MULTIPLY(z2, - FIX_0_601344887) /* sqrt(2) * (c5-c1) */

+	 + MULTIPLY(z3, FIX_0_899976223) /* sqrt(2) * (c3-c7) */

+	 + MULTIPLY(z4, FIX_2_562915447); /* sqrt(2) * (c1+c3) */

+

+    /* Final output stage */

+    

+    outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp2,

+					  CONST_BITS+PASS1_BITS+3+1)

+			    & RANGE_MASK];

+    outptr[3] = range_limit[(int) DESCALE(tmp10 - tmp2,

+					  CONST_BITS+PASS1_BITS+3+1)

+			    & RANGE_MASK];

+    outptr[1] = range_limit[(int) DESCALE(tmp12 + tmp0,

+					  CONST_BITS+PASS1_BITS+3+1)

+			    & RANGE_MASK];

+    outptr[2] = range_limit[(int) DESCALE(tmp12 - tmp0,

+					  CONST_BITS+PASS1_BITS+3+1)

+			    & RANGE_MASK];

+    

+    wsptr += DCTSIZE;		/* advance pointer to next row */

+  }

+}

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients,

+ * producing a reduced-size 2x2 output block.

+ */

+

+GLOBAL void

+jpeg_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JCOEFPTR coef_block,

+	       JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  INT32 tmp0, tmp10, z1;

+  JCOEFPTR inptr;

+  ISLOW_MULT_TYPE * quantptr;

+  int * wsptr;

+  JSAMPROW outptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  int ctr;

+  int workspace[DCTSIZE*2];	/* buffers data between passes */

+  SHIFT_TEMPS

+

+  /* Pass 1: process columns from input, store into work array. */

+

+  inptr = coef_block;

+  quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;

+  wsptr = workspace;

+  for (ctr = DCTSIZE; ctr > 0; inptr++, quantptr++, wsptr++, ctr--) {

+    /* Don't bother to process columns 2,4,6 */

+    if (ctr == DCTSIZE-2 || ctr == DCTSIZE-4 || ctr == DCTSIZE-6)

+      continue;

+    if ((inptr[DCTSIZE*1] | inptr[DCTSIZE*3] |

+	 inptr[DCTSIZE*5] | inptr[DCTSIZE*7]) == 0) {

+      /* AC terms all zero; we need not examine terms 2,4,6 for 2x2 output */

+      int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;

+      

+      wsptr[DCTSIZE*0] = dcval;

+      wsptr[DCTSIZE*1] = dcval;

+      

+      continue;

+    }

+    

+    /* Even part */

+    

+    z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);

+    tmp10 = z1 << (CONST_BITS+2);

+    

+    /* Odd part */

+

+    z1 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);

+    tmp0 = MULTIPLY(z1, - FIX_0_720959822); /* sqrt(2) * (c7-c5+c3-c1) */

+    z1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);

+    tmp0 += MULTIPLY(z1, FIX_0_850430095); /* sqrt(2) * (-c1+c3+c5+c7) */

+    z1 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);

+    tmp0 += MULTIPLY(z1, - FIX_1_272758580); /* sqrt(2) * (-c1+c3-c5-c7) */

+    z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);

+    tmp0 += MULTIPLY(z1, FIX_3_624509785); /* sqrt(2) * (c1+c3+c5+c7) */

+

+    /* Final output stage */

+    

+    wsptr[DCTSIZE*0] = (int) DESCALE(tmp10 + tmp0, CONST_BITS-PASS1_BITS+2);

+    wsptr[DCTSIZE*1] = (int) DESCALE(tmp10 - tmp0, CONST_BITS-PASS1_BITS+2);

+  }

+  

+  /* Pass 2: process 2 rows from work array, store into output array. */

+

+  wsptr = workspace;

+  for (ctr = 0; ctr < 2; ctr++) {

+    outptr = output_buf[ctr] + output_col;

+    /* It's not clear whether a zero row test is worthwhile here ... */

+

+#ifndef NO_ZERO_ROW_TEST

+    if ((wsptr[1] | wsptr[3] | wsptr[5] | wsptr[7]) == 0) {

+      /* AC terms all zero */

+      JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3)

+				  & RANGE_MASK];

+      

+      outptr[0] = dcval;

+      outptr[1] = dcval;

+      

+      wsptr += DCTSIZE;		/* advance pointer to next row */

+      continue;

+    }

+#endif

+    

+    /* Even part */

+    

+    tmp10 = ((INT32) wsptr[0]) << (CONST_BITS+2);

+    

+    /* Odd part */

+

+    tmp0 = MULTIPLY((INT32) wsptr[7], - FIX_0_720959822) /* sqrt(2) * (c7-c5+c3-c1) */

+	 + MULTIPLY((INT32) wsptr[5], FIX_0_850430095) /* sqrt(2) * (-c1+c3+c5+c7) */

+	 + MULTIPLY((INT32) wsptr[3], - FIX_1_272758580) /* sqrt(2) * (-c1+c3-c5-c7) */

+	 + MULTIPLY((INT32) wsptr[1], FIX_3_624509785); /* sqrt(2) * (c1+c3+c5+c7) */

+

+    /* Final output stage */

+    

+    outptr[0] = range_limit[(int) DESCALE(tmp10 + tmp0,

+					  CONST_BITS+PASS1_BITS+3+2)

+			    & RANGE_MASK];

+    outptr[1] = range_limit[(int) DESCALE(tmp10 - tmp0,

+					  CONST_BITS+PASS1_BITS+3+2)

+			    & RANGE_MASK];

+    

+    wsptr += DCTSIZE;		/* advance pointer to next row */

+  }

+}

+

+

+/*

+ * Perform dequantization and inverse DCT on one block of coefficients,

+ * producing a reduced-size 1x1 output block.

+ */

+

+GLOBAL void

+jpeg_idct_1x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr,

+	       JCOEFPTR coef_block,

+	       JSAMPARRAY output_buf, JDIMENSION output_col)

+{

+  int dcval;

+  ISLOW_MULT_TYPE * quantptr;

+  JSAMPLE *range_limit = IDCT_range_limit(cinfo);

+  SHIFT_TEMPS

+

+  /* We hardly need an inverse DCT routine for this: just take the

+   * average pixel value, which is one-eighth of the DC coefficient.

+   */

+  quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;

+  dcval = DEQUANTIZE(coef_block[0], quantptr[0]);

+  dcval = (int) DESCALE((INT32) dcval, 3);

+

+  output_buf[0][output_col] = range_limit[dcval & RANGE_MASK];

+}

+

+#endif /* IDCT_SCALING_SUPPORTED */

diff --git a/code/jpeg-6/jinclude.h b/code/jpeg-6/jinclude.h
new file mode 100755
index 0000000..99f535d
--- /dev/null
+++ b/code/jpeg-6/jinclude.h
@@ -0,0 +1,116 @@
+/*

+ * jinclude.h

+ *

+ * Copyright (C) 1991-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file exists to provide a single place to fix any problems with

+ * including the wrong system include files.  (Common problems are taken

+ * care of by the standard jconfig symbols, but on really weird systems

+ * you may have to edit this file.)

+ *

+ * NOTE: this file is NOT intended to be included by applications using the

+ * JPEG library.  Most applications need only include jpeglib.h.

+ */

+

+

+#ifdef _WIN32

+

+#pragma warning(disable : 4018)     // signed/unsigned mismatch

+#pragma warning(disable : 4032)

+#pragma warning(disable : 4051)

+#pragma warning(disable : 4057)		// slightly different base types

+#pragma warning(disable : 4100)		// unreferenced formal parameter

+#pragma warning(disable : 4115)

+#pragma warning(disable : 4125)		// decimal digit terminates octal escape sequence

+#pragma warning(disable : 4127)		// conditional expression is constant

+#pragma warning(disable : 4136)

+#pragma warning(disable : 4152)		// nonstandard extension, function/data pointer conversion in expression

+#pragma warning(disable : 4201)

+#pragma warning(disable : 4214)

+#pragma warning(disable : 4244)

+#pragma warning(disable : 4305)		// truncation from const double to float

+#pragma warning(disable : 4310)		// cast truncates constant value

+#pragma warning(disable:  4505) 	// unreferenced local function has been removed

+#pragma warning(disable : 4514)

+#pragma warning(disable : 4702)		// unreachable code

+#pragma warning(disable : 4711)		// selected for automatic inline expansion

+#pragma warning(disable : 4220)		// varargs matches remaining parameters

+#pragma warning(disable : 4761)		// integral size mismatch 

+#endif

+

+/* Include auto-config file to find out which system include files we need. */

+

+#include "../jpeg-6/jconfig.h"		/* auto configuration options */

+#define JCONFIG_INCLUDED	/* so that jpeglib.h doesn't do it again */

+

+/*

+ * We need the NULL macro and size_t typedef.

+ * On an ANSI-conforming system it is sufficient to include <stddef.h>.

+ * Otherwise, we get them from <stdlib.h> or <stdio.h>; we may have to

+ * pull in <sys/types.h> as well.

+ * Note that the core JPEG library does not require <stdio.h>;

+ * only the default error handler and data source/destination modules do.

+ * But we must pull it in because of the references to FILE in jpeglib.h.

+ * You can remove those references if you want to compile without <stdio.h>.

+ */

+

+#ifdef HAVE_STDDEF_H

+#include <stddef.h>

+#endif

+

+#ifdef HAVE_STDLIB_H

+#include <stdlib.h>

+#endif

+

+#ifdef NEED_SYS_TYPES_H

+#include <sys/types.h>

+#endif

+

+#include <stdio.h>

+

+/*

+ * We need memory copying and zeroing functions, plus strncpy().

+ * ANSI and System V implementations declare these in <string.h>.

+ * BSD doesn't have the mem() functions, but it does have bcopy()/bzero().

+ * Some systems may declare memset and memcpy in <memory.h>.

+ *

+ * NOTE: we assume the size parameters to these functions are of type size_t.

+ * Change the casts in these macros if not!

+ */

+

+#ifdef NEED_BSD_STRINGS

+

+#include <strings.h>

+#define MEMZERO(target,size)	bzero((void *)(target), (size_t)(size))

+#define MEMCOPY(dest,src,size)	bcopy((const void *)(src), (void *)(dest), (size_t)(size))

+

+#else /* not BSD, assume ANSI/SysV string lib */

+

+#include <string.h>

+#define MEMZERO(target,size)	memset((void *)(target), 0, (size_t)(size))

+#define MEMCOPY(dest,src,size)	memcpy((void *)(dest), (const void *)(src), (size_t)(size))

+

+#endif

+

+/*

+ * In ANSI C, and indeed any rational implementation, size_t is also the

+ * type returned by sizeof().  However, it seems there are some irrational

+ * implementations out there, in which sizeof() returns an int even though

+ * size_t is defined as long or unsigned long.  To ensure consistent results

+ * we always use this SIZEOF() macro in place of using sizeof() directly.

+ */

+

+#define SIZEOF(object)	((size_t) sizeof(object))

+

+/*

+ * The modules that use fread() and fwrite() always invoke them through

+ * these macros.  On some systems you may need to twiddle the argument casts.

+ * CAUTION: argument order is different from underlying functions!

+ */

+

+#define JFREAD(file,buf,sizeofbuf)  \

+  ((size_t) fread((void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))

+#define JFWRITE(file,buf,sizeofbuf)  \

+  ((size_t) fwrite((const void *) (buf), (size_t) 1, (size_t) (sizeofbuf), (file)))

diff --git a/code/jpeg-6/jload.c b/code/jpeg-6/jload.c
new file mode 100755
index 0000000..5cbec78
--- /dev/null
+++ b/code/jpeg-6/jload.c
@@ -0,0 +1,145 @@
+

+#include "../game/q_shared.h"

+#include "../qcommon/qcommon.h"

+

+/*

+ * Include file for users of JPEG library.

+ * You will need to have included system headers that define at least

+ * the typedefs FILE and size_t before you can include jpeglib.h.

+ * (stdio.h is sufficient on ANSI-conforming systems.)

+ * You may also wish to include "jerror.h".

+ */

+

+#include "jpeglib.h"

+

+

+int LoadJPG( const char *filename, unsigned char **pic, int *width, int *height ) {

+  /* This struct contains the JPEG decompression parameters and pointers to

+   * working space (which is allocated as needed by the JPEG library).

+   */

+  struct jpeg_decompress_struct cinfo;

+  /* We use our private extension JPEG error handler.

+   * Note that this struct must live as long as the main JPEG parameter

+   * struct, to avoid dangling-pointer problems.

+   */

+  /* This struct represents a JPEG error handler.  It is declared separately

+   * because applications often want to supply a specialized error handler

+   * (see the second half of this file for an example).  But here we just

+   * take the easy way out and use the standard error handler, which will

+   * print a message on stderr and call exit() if compression fails.

+   * Note that this struct must live as long as the main JPEG parameter

+   * struct, to avoid dangling-pointer problems.

+   */

+  struct jpeg_error_mgr jerr;

+  /* More stuff */

+  fileHandle_t infile;		/* source file */

+  JSAMPARRAY buffer;		/* Output row buffer */

+  int row_stride;		/* physical row width in output buffer */

+  unsigned char *out;

+

+  /* In this example we want to open the input file before doing anything else,

+   * so that the setjmp() error recovery below can assume the file is open.

+   * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that

+   * requires it in order to read binary files.

+   */

+

+  FS_FOpenFileRead( filename, &infile, qfalse );

+  if (infile == 0) {

+    return 0;

+  }

+

+  /* Step 1: allocate and initialize JPEG decompression object */

+

+  /* We have to set up the error handler first, in case the initialization

+   * step fails.  (Unlikely, but it could happen if you are out of memory.)

+   * This routine fills in the contents of struct jerr, and returns jerr's

+   * address which we place into the link field in cinfo.

+   */

+  cinfo.err = jpeg_std_error(&jerr);

+

+  /* Now we can initialize the JPEG decompression object. */

+  jpeg_create_decompress(&cinfo);

+

+  /* Step 2: specify data source (eg, a file) */

+

+  jpeg_stdio_src(&cinfo, infile);

+

+  /* Step 3: read file parameters with jpeg_read_header() */

+

+  (void) jpeg_read_header(&cinfo, TRUE);

+  /* We can ignore the return value from jpeg_read_header since

+   *   (a) suspension is not possible with the stdio data source, and

+   *   (b) we passed TRUE to reject a tables-only JPEG file as an error.

+   * See libjpeg.doc for more info.

+   */

+

+  /* Step 4: set parameters for decompression */

+

+  /* In this example, we don't need to change any of the defaults set by

+   * jpeg_read_header(), so we do nothing here.

+   */

+

+  /* Step 5: Start decompressor */

+

+  (void) jpeg_start_decompress(&cinfo);

+  /* We can ignore the return value since suspension is not possible

+   * with the stdio data source.

+   */

+

+  /* We may need to do some setup of our own at this point before reading

+   * the data.  After jpeg_start_decompress() we have the correct scaled

+   * output image dimensions available, as well as the output colormap

+   * if we asked for color quantization.

+   * In this example, we need to make an output work buffer of the right size.

+   */ 

+  /* JSAMPLEs per row in output buffer */

+  row_stride = cinfo.output_width * cinfo.output_components;

+

+  out = Z_Malloc(cinfo.output_width*cinfo.output_height*cinfo.output_components);

+

+  *pic = out;

+  *width = cinfo.output_width;

+  *height = cinfo.output_height;

+

+  /* Step 6: while (scan lines remain to be read) */

+  /*           jpeg_read_scanlines(...); */

+

+  /* Here we use the library's state variable cinfo.output_scanline as the

+   * loop counter, so that we don't have to keep track ourselves.

+   */

+  while (cinfo.output_scanline < cinfo.output_height) {

+    /* jpeg_read_scanlines expects an array of pointers to scanlines.

+     * Here the array is only one element long, but you could ask for

+     * more than one scanline at a time if that's more convenient.

+     */

+	buffer = (JSAMPARRAY)out+(row_stride*cinfo.output_scanline);

+    (void) jpeg_read_scanlines(&cinfo, buffer, 1);

+  }

+

+  /* Step 7: Finish decompression */

+

+  (void) jpeg_finish_decompress(&cinfo);

+  /* We can ignore the return value since suspension is not possible

+   * with the stdio data source.

+   */

+

+  /* Step 8: Release JPEG decompression object */

+

+  /* This is an important step since it will release a good deal of memory. */

+  jpeg_destroy_decompress(&cinfo);

+

+  /* After finish_decompress, we can close the input file.

+   * Here we postpone it until after no more JPEG errors are possible,

+   * so as to simplify the setjmp error logic above.  (Actually, I don't

+   * think that jpeg_destroy can do an error exit, but why assume anything...)

+   */

+  FS_FCloseFile(infile);

+

+  /* At this point you may want to check to see whether any corrupt-data

+   * warnings occurred (test whether jerr.pub.num_warnings is nonzero).

+   */

+

+  /* And we're done! */

+  return 1;

+}

+

diff --git a/code/jpeg-6/jmemansi.c b/code/jpeg-6/jmemansi.c
new file mode 100755
index 0000000..b560d20
--- /dev/null
+++ b/code/jpeg-6/jmemansi.c
@@ -0,0 +1,167 @@
+/*

+ * jmemansi.c

+ *

+ * Copyright (C) 1992-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file provides a simple generic implementation of the system-

+ * dependent portion of the JPEG memory manager.  This implementation

+ * assumes that you have the ANSI-standard library routine tmpfile().

+ * Also, the problem of determining the amount of memory available

+ * is shoved onto the user.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jmemsys.h"		/* import the system-dependent declarations */

+

+#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare malloc(),free() */

+extern void * malloc JPP((size_t size));

+extern void free JPP((void *ptr));

+#endif

+

+#ifndef SEEK_SET		/* pre-ANSI systems may not define this; */

+#define SEEK_SET  0		/* if not, assume 0 is correct */

+#endif

+

+

+/*

+ * Memory allocation and freeing are controlled by the regular library

+ * routines malloc() and free().

+ */

+

+GLOBAL void *

+jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void *) malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)

+{

+  free(object);

+}

+

+

+/*

+ * "Large" objects are treated the same as "small" ones.

+ * NB: although we include FAR keywords in the routine declarations,

+ * this file won't actually work in 80x86 small/medium model; at least,

+ * you probably won't be able to process useful-size images in only 64KB.

+ */

+

+GLOBAL void FAR *

+jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void FAR *) malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)

+{

+  free(object);

+}

+

+

+/*

+ * This routine computes the total memory space available for allocation.

+ * It's impossible to do this in a portable way; our current solution is

+ * to make the user tell us (with a default value set at compile time).

+ * If you can actually get the available space, it's a good idea to subtract

+ * a slop factor of 5% or so.

+ */

+

+#ifndef DEFAULT_MAX_MEM		/* so can override from makefile */

+#define DEFAULT_MAX_MEM		1000000L /* default: one megabyte */

+#endif

+

+GLOBAL long

+jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,

+		    long max_bytes_needed, long already_allocated)

+{

+  return cinfo->mem->max_memory_to_use - already_allocated;

+}

+

+

+/*

+ * Backing store (temporary file) management.

+ * Backing store objects are only used when the value returned by

+ * jpeg_mem_available is less than the total space needed.  You can dispense

+ * with these routines if you have plenty of virtual memory; see jmemnobs.c.

+ */

+

+

+METHODDEF void

+read_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+		    void FAR * buffer_address,

+		    long file_offset, long byte_count)

+{

+  if (fseek(info->temp_file, file_offset, SEEK_SET))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  if (JFREAD(info->temp_file, buffer_address, byte_count)

+      != (size_t) byte_count)

+    ERREXIT(cinfo, JERR_TFILE_READ);

+}

+

+

+METHODDEF void

+write_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+		     void FAR * buffer_address,

+		     long file_offset, long byte_count)

+{

+  if (fseek(info->temp_file, file_offset, SEEK_SET))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  if (JFWRITE(info->temp_file, buffer_address, byte_count)

+      != (size_t) byte_count)

+    ERREXIT(cinfo, JERR_TFILE_WRITE);

+}

+

+

+METHODDEF void

+close_backing_store (j_common_ptr cinfo, backing_store_ptr info)

+{

+  fclose(info->temp_file);

+  /* Since this implementation uses tmpfile() to create the file,

+   * no explicit file deletion is needed.

+   */

+}

+

+

+/*

+ * Initial opening of a backing-store object.

+ *

+ * This version uses tmpfile(), which constructs a suitable file name

+ * behind the scenes.  We don't have to use info->temp_name[] at all;

+ * indeed, we can't even find out the actual name of the temp file.

+ */

+

+GLOBAL void

+jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+			 long total_bytes_needed)

+{

+  if ((info->temp_file = tmpfile()) == NULL)

+    ERREXITS(cinfo, JERR_TFILE_CREATE, "");

+  info->read_backing_store = read_backing_store;

+  info->write_backing_store = write_backing_store;

+  info->close_backing_store = close_backing_store;

+}

+

+

+/*

+ * These routines take care of any system-dependent initialization and

+ * cleanup required.

+ */

+

+GLOBAL long

+jpeg_mem_init (j_common_ptr cinfo)

+{

+  return DEFAULT_MAX_MEM;	/* default for max_memory_to_use */

+}

+

+GLOBAL void

+jpeg_mem_term (j_common_ptr cinfo)

+{

+  /* no work */

+}

diff --git a/code/jpeg-6/jmemdos.c b/code/jpeg-6/jmemdos.c
new file mode 100755
index 0000000..fd4a923
--- /dev/null
+++ b/code/jpeg-6/jmemdos.c
@@ -0,0 +1,634 @@
+/*

+ * jmemdos.c

+ *

+ * Copyright (C) 1992-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file provides an MS-DOS-compatible implementation of the system-

+ * dependent portion of the JPEG memory manager.  Temporary data can be

+ * stored in extended or expanded memory as well as in regular DOS files.

+ *

+ * If you use this file, you must be sure that NEED_FAR_POINTERS is defined

+ * if you compile in a small-data memory model; it should NOT be defined if

+ * you use a large-data memory model.  This file is not recommended if you

+ * are using a flat-memory-space 386 environment such as DJGCC or Watcom C.

+ * Also, this code will NOT work if struct fields are aligned on greater than

+ * 2-byte boundaries.

+ *

+ * Based on code contributed by Ge' Weijers.

+ */

+

+/*

+ * If you have both extended and expanded memory, you may want to change the

+ * order in which they are tried in jopen_backing_store.  On a 286 machine

+ * expanded memory is usually faster, since extended memory access involves

+ * an expensive protected-mode-and-back switch.  On 386 and better, extended

+ * memory is usually faster.  As distributed, the code tries extended memory

+ * first (what? not everyone has a 386? :-).

+ *

+ * You can disable use of extended/expanded memory entirely by altering these

+ * definitions or overriding them from the Makefile (eg, -DEMS_SUPPORTED=0).

+ */

+

+#ifndef XMS_SUPPORTED

+#define XMS_SUPPORTED  1

+#endif

+#ifndef EMS_SUPPORTED

+#define EMS_SUPPORTED  1

+#endif

+

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jmemsys.h"		/* import the system-dependent declarations */

+

+#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare these */

+extern void * malloc JPP((size_t size));

+extern void free JPP((void *ptr));

+extern char * getenv JPP((const char * name));

+#endif

+

+#ifdef NEED_FAR_POINTERS

+

+#ifdef __TURBOC__

+/* These definitions work for Borland C (Turbo C) */

+#include <alloc.h>		/* need farmalloc(), farfree() */

+#define far_malloc(x)	farmalloc(x)

+#define far_free(x)	farfree(x)

+#else

+/* These definitions work for Microsoft C and compatible compilers */

+#include <malloc.h>		/* need _fmalloc(), _ffree() */

+#define far_malloc(x)	_fmalloc(x)

+#define far_free(x)	_ffree(x)

+#endif

+

+#else /* not NEED_FAR_POINTERS */

+

+#define far_malloc(x)	malloc(x)

+#define far_free(x)	free(x)

+

+#endif /* NEED_FAR_POINTERS */

+

+#ifdef DONT_USE_B_MODE		/* define mode parameters for fopen() */

+#define READ_BINARY	"r"

+#else

+#define READ_BINARY	"rb"

+#endif

+

+#if MAX_ALLOC_CHUNK >= 65535L	/* make sure jconfig.h got this right */

+  MAX_ALLOC_CHUNK should be less than 64K. /* deliberate syntax error */

+#endif

+

+

+/*

+ * Declarations for assembly-language support routines (see jmemdosa.asm).

+ *

+ * The functions are declared "far" as are all pointer arguments;

+ * this ensures the assembly source code will work regardless of the

+ * compiler memory model.  We assume "short" is 16 bits, "long" is 32.

+ */

+

+typedef void far * XMSDRIVER;	/* actually a pointer to code */

+typedef struct {		/* registers for calling XMS driver */

+	unsigned short ax, dx, bx;

+	void far * ds_si;

+      } XMScontext;

+typedef struct {		/* registers for calling EMS driver */

+	unsigned short ax, dx, bx;

+	void far * ds_si;

+      } EMScontext;

+

+EXTERN short far jdos_open JPP((short far * handle, char far * filename));

+EXTERN short far jdos_close JPP((short handle));

+EXTERN short far jdos_seek JPP((short handle, long offset));

+EXTERN short far jdos_read JPP((short handle, void far * buffer,

+				unsigned short count));

+EXTERN short far jdos_write JPP((short handle, void far * buffer,

+				 unsigned short count));

+EXTERN void far jxms_getdriver JPP((XMSDRIVER far *));

+EXTERN void far jxms_calldriver JPP((XMSDRIVER, XMScontext far *));

+EXTERN short far jems_available JPP((void));

+EXTERN void far jems_calldriver JPP((EMScontext far *));

+

+

+/*

+ * Selection of a file name for a temporary file.

+ * This is highly system-dependent, and you may want to customize it.

+ */

+

+static int next_file_num;	/* to distinguish among several temp files */

+

+LOCAL void

+select_file_name (char * fname)

+{

+  const char * env;

+  char * ptr;

+  FILE * tfile;

+

+  /* Keep generating file names till we find one that's not in use */

+  for (;;) {

+    /* Get temp directory name from environment TMP or TEMP variable;

+     * if none, use "."

+     */

+    if ((env = (const char *) getenv("TMP")) == NULL)

+      if ((env = (const char *) getenv("TEMP")) == NULL)

+	env = ".";

+    if (*env == '\0')		/* null string means "." */

+      env = ".";

+    ptr = fname;		/* copy name to fname */

+    while (*env != '\0')

+      *ptr++ = *env++;

+    if (ptr[-1] != '\\' && ptr[-1] != '/')

+      *ptr++ = '\\';		/* append backslash if not in env variable */

+    /* Append a suitable file name */

+    next_file_num++;		/* advance counter */

+    sprintf(ptr, "JPG%03d.TMP", next_file_num);

+    /* Probe to see if file name is already in use */

+    if ((tfile = fopen(fname, READ_BINARY)) == NULL)

+      break;

+    fclose(tfile);		/* oops, it's there; close tfile & try again */

+  }

+}

+

+

+/*

+ * Near-memory allocation and freeing are controlled by the regular library

+ * routines malloc() and free().

+ */

+

+GLOBAL void *

+jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void *) malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)

+{

+  free(object);

+}

+

+

+/*

+ * "Large" objects are allocated in far memory, if possible

+ */

+

+GLOBAL void FAR *

+jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void FAR *) far_malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)

+{

+  far_free(object);

+}

+

+

+/*

+ * This routine computes the total memory space available for allocation.

+ * It's impossible to do this in a portable way; our current solution is

+ * to make the user tell us (with a default value set at compile time).

+ * If you can actually get the available space, it's a good idea to subtract

+ * a slop factor of 5% or so.

+ */

+

+#ifndef DEFAULT_MAX_MEM		/* so can override from makefile */

+#define DEFAULT_MAX_MEM		300000L /* for total usage about 450K */

+#endif

+

+GLOBAL long

+jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,

+		    long max_bytes_needed, long already_allocated)

+{

+  return cinfo->mem->max_memory_to_use - already_allocated;

+}

+

+

+/*

+ * Backing store (temporary file) management.

+ * Backing store objects are only used when the value returned by

+ * jpeg_mem_available is less than the total space needed.  You can dispense

+ * with these routines if you have plenty of virtual memory; see jmemnobs.c.

+ */

+

+/*

+ * For MS-DOS we support three types of backing storage:

+ *   1. Conventional DOS files.  We access these by direct DOS calls rather

+ *      than via the stdio package.  This provides a bit better performance,

+ *      but the real reason is that the buffers to be read or written are FAR.

+ *      The stdio library for small-data memory models can't cope with that.

+ *   2. Extended memory, accessed per the XMS V2.0 specification.

+ *   3. Expanded memory, accessed per the LIM/EMS 4.0 specification.

+ * You'll need copies of those specs to make sense of the related code.

+ * The specs are available by Internet FTP from the SIMTEL archives 

+ * (oak.oakland.edu and its various mirror sites).  See files

+ * pub/msdos/microsoft/xms20.arc and pub/msdos/info/limems41.zip.

+ */

+

+

+/*

+ * Access methods for a DOS file.

+ */

+

+

+METHODDEF void

+read_file_store (j_common_ptr cinfo, backing_store_ptr info,

+		 void FAR * buffer_address,

+		 long file_offset, long byte_count)

+{

+  if (jdos_seek(info->handle.file_handle, file_offset))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */

+  if (byte_count > 65535L)	/* safety check */

+    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);

+  if (jdos_read(info->handle.file_handle, buffer_address,

+		(unsigned short) byte_count))

+    ERREXIT(cinfo, JERR_TFILE_READ);

+}

+

+

+METHODDEF void

+write_file_store (j_common_ptr cinfo, backing_store_ptr info,

+		  void FAR * buffer_address,

+		  long file_offset, long byte_count)

+{

+  if (jdos_seek(info->handle.file_handle, file_offset))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */

+  if (byte_count > 65535L)	/* safety check */

+    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);

+  if (jdos_write(info->handle.file_handle, buffer_address,

+		 (unsigned short) byte_count))

+    ERREXIT(cinfo, JERR_TFILE_WRITE);

+}

+

+

+METHODDEF void

+close_file_store (j_common_ptr cinfo, backing_store_ptr info)

+{

+  jdos_close(info->handle.file_handle);	/* close the file */

+  remove(info->temp_name);	/* delete the file */

+/* If your system doesn't have remove(), try unlink() instead.

+ * remove() is the ANSI-standard name for this function, but

+ * unlink() was more common in pre-ANSI systems.

+ */

+  TRACEMSS(cinfo, 1, JTRC_TFILE_CLOSE, info->temp_name);

+}

+

+

+LOCAL boolean

+open_file_store (j_common_ptr cinfo, backing_store_ptr info,

+		 long total_bytes_needed)

+{

+  short handle;

+

+  select_file_name(info->temp_name);

+  if (jdos_open((short far *) & handle, (char far *) info->temp_name)) {

+    /* might as well exit since jpeg_open_backing_store will fail anyway */

+    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);

+    return FALSE;

+  }

+  info->handle.file_handle = handle;

+  info->read_backing_store = read_file_store;

+  info->write_backing_store = write_file_store;

+  info->close_backing_store = close_file_store;

+  TRACEMSS(cinfo, 1, JTRC_TFILE_OPEN, info->temp_name);

+  return TRUE;			/* succeeded */

+}

+

+

+/*

+ * Access methods for extended memory.

+ */

+

+#if XMS_SUPPORTED

+

+static XMSDRIVER xms_driver;	/* saved address of XMS driver */

+

+typedef union {			/* either long offset or real-mode pointer */

+	long offset;

+	void far * ptr;

+      } XMSPTR;

+

+typedef struct {		/* XMS move specification structure */

+	long length;

+	XMSH src_handle;

+	XMSPTR src;

+	XMSH dst_handle;

+	XMSPTR dst;

+      } XMSspec;

+

+#define ODD(X)	(((X) & 1L) != 0)

+

+

+METHODDEF void

+read_xms_store (j_common_ptr cinfo, backing_store_ptr info,

+		void FAR * buffer_address,

+		long file_offset, long byte_count)

+{

+  XMScontext ctx;

+  XMSspec spec;

+  char endbuffer[2];

+

+  /* The XMS driver can't cope with an odd length, so handle the last byte

+   * specially if byte_count is odd.  We don't expect this to be common.

+   */

+

+  spec.length = byte_count & (~ 1L);

+  spec.src_handle = info->handle.xms_handle;

+  spec.src.offset = file_offset;

+  spec.dst_handle = 0;

+  spec.dst.ptr = buffer_address;

+  

+  ctx.ds_si = (void far *) & spec;

+  ctx.ax = 0x0b00;		/* EMB move */

+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

+  if (ctx.ax != 1)

+    ERREXIT(cinfo, JERR_XMS_READ);

+

+  if (ODD(byte_count)) {

+    read_xms_store(cinfo, info, (void FAR *) endbuffer,

+		   file_offset + byte_count - 1L, 2L);

+    ((char FAR *) buffer_address)[byte_count - 1L] = endbuffer[0];

+  }

+}

+

+

+METHODDEF void

+write_xms_store (j_common_ptr cinfo, backing_store_ptr info,

+		 void FAR * buffer_address,

+		 long file_offset, long byte_count)

+{

+  XMScontext ctx;

+  XMSspec spec;

+  char endbuffer[2];

+

+  /* The XMS driver can't cope with an odd length, so handle the last byte

+   * specially if byte_count is odd.  We don't expect this to be common.

+   */

+

+  spec.length = byte_count & (~ 1L);

+  spec.src_handle = 0;

+  spec.src.ptr = buffer_address;

+  spec.dst_handle = info->handle.xms_handle;

+  spec.dst.offset = file_offset;

+

+  ctx.ds_si = (void far *) & spec;

+  ctx.ax = 0x0b00;		/* EMB move */

+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

+  if (ctx.ax != 1)

+    ERREXIT(cinfo, JERR_XMS_WRITE);

+

+  if (ODD(byte_count)) {

+    read_xms_store(cinfo, info, (void FAR *) endbuffer,

+		   file_offset + byte_count - 1L, 2L);

+    endbuffer[0] = ((char FAR *) buffer_address)[byte_count - 1L];

+    write_xms_store(cinfo, info, (void FAR *) endbuffer,

+		    file_offset + byte_count - 1L, 2L);

+  }

+}

+

+

+METHODDEF void

+close_xms_store (j_common_ptr cinfo, backing_store_ptr info)

+{

+  XMScontext ctx;

+

+  ctx.dx = info->handle.xms_handle;

+  ctx.ax = 0x0a00;

+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

+  TRACEMS1(cinfo, 1, JTRC_XMS_CLOSE, info->handle.xms_handle);

+  /* we ignore any error return from the driver */

+}

+

+

+LOCAL boolean

+open_xms_store (j_common_ptr cinfo, backing_store_ptr info,

+		long total_bytes_needed)

+{

+  XMScontext ctx;

+

+  /* Get address of XMS driver */

+  jxms_getdriver((XMSDRIVER far *) & xms_driver);

+  if (xms_driver == NULL)

+    return FALSE;		/* no driver to be had */

+

+  /* Get version number, must be >= 2.00 */

+  ctx.ax = 0x0000;

+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

+  if (ctx.ax < (unsigned short) 0x0200)

+    return FALSE;

+

+  /* Try to get space (expressed in kilobytes) */

+  ctx.dx = (unsigned short) ((total_bytes_needed + 1023L) >> 10);

+  ctx.ax = 0x0900;

+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

+  if (ctx.ax != 1)

+    return FALSE;

+

+  /* Succeeded, save the handle and away we go */

+  info->handle.xms_handle = ctx.dx;

+  info->read_backing_store = read_xms_store;

+  info->write_backing_store = write_xms_store;

+  info->close_backing_store = close_xms_store;

+  TRACEMS1(cinfo, 1, JTRC_XMS_OPEN, ctx.dx);

+  return TRUE;			/* succeeded */

+}

+

+#endif /* XMS_SUPPORTED */

+

+

+/*

+ * Access methods for expanded memory.

+ */

+

+#if EMS_SUPPORTED

+

+/* The EMS move specification structure requires word and long fields aligned

+ * at odd byte boundaries.  Some compilers will align struct fields at even

+ * byte boundaries.  While it's usually possible to force byte alignment,

+ * that causes an overall performance penalty and may pose problems in merging

+ * JPEG into a larger application.  Instead we accept some rather dirty code

+ * here.  Note this code would fail if the hardware did not allow odd-byte

+ * word & long accesses, but all 80x86 CPUs do.

+ */

+

+typedef void far * EMSPTR;

+

+typedef union {			/* EMS move specification structure */

+	long length;		/* It's easy to access first 4 bytes */

+	char bytes[18];		/* Misaligned fields in here! */

+      } EMSspec;

+

+/* Macros for accessing misaligned fields */

+#define FIELD_AT(spec,offset,type)  (*((type *) &(spec.bytes[offset])))

+#define SRC_TYPE(spec)		FIELD_AT(spec,4,char)

+#define SRC_HANDLE(spec)	FIELD_AT(spec,5,EMSH)

+#define SRC_OFFSET(spec)	FIELD_AT(spec,7,unsigned short)

+#define SRC_PAGE(spec)		FIELD_AT(spec,9,unsigned short)

+#define SRC_PTR(spec)		FIELD_AT(spec,7,EMSPTR)

+#define DST_TYPE(spec)		FIELD_AT(spec,11,char)

+#define DST_HANDLE(spec)	FIELD_AT(spec,12,EMSH)

+#define DST_OFFSET(spec)	FIELD_AT(spec,14,unsigned short)

+#define DST_PAGE(spec)		FIELD_AT(spec,16,unsigned short)

+#define DST_PTR(spec)		FIELD_AT(spec,14,EMSPTR)

+

+#define EMSPAGESIZE	16384L	/* gospel, see the EMS specs */

+

+#define HIBYTE(W)  (((W) >> 8) & 0xFF)

+#define LOBYTE(W)  ((W) & 0xFF)

+

+

+METHODDEF void

+read_ems_store (j_common_ptr cinfo, backing_store_ptr info,

+		void FAR * buffer_address,

+		long file_offset, long byte_count)

+{

+  EMScontext ctx;

+  EMSspec spec;

+

+  spec.length = byte_count;

+  SRC_TYPE(spec) = 1;

+  SRC_HANDLE(spec) = info->handle.ems_handle;

+  SRC_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);

+  SRC_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);

+  DST_TYPE(spec) = 0;

+  DST_HANDLE(spec) = 0;

+  DST_PTR(spec)    = buffer_address;

+  

+  ctx.ds_si = (void far *) & spec;

+  ctx.ax = 0x5700;		/* move memory region */

+  jems_calldriver((EMScontext far *) & ctx);

+  if (HIBYTE(ctx.ax) != 0)

+    ERREXIT(cinfo, JERR_EMS_READ);

+}

+

+

+METHODDEF void

+write_ems_store (j_common_ptr cinfo, backing_store_ptr info,

+		 void FAR * buffer_address,

+		 long file_offset, long byte_count)

+{

+  EMScontext ctx;

+  EMSspec spec;

+

+  spec.length = byte_count;

+  SRC_TYPE(spec) = 0;

+  SRC_HANDLE(spec) = 0;

+  SRC_PTR(spec)    = buffer_address;

+  DST_TYPE(spec) = 1;

+  DST_HANDLE(spec) = info->handle.ems_handle;

+  DST_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);

+  DST_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);

+  

+  ctx.ds_si = (void far *) & spec;

+  ctx.ax = 0x5700;		/* move memory region */

+  jems_calldriver((EMScontext far *) & ctx);

+  if (HIBYTE(ctx.ax) != 0)

+    ERREXIT(cinfo, JERR_EMS_WRITE);

+}

+

+

+METHODDEF void

+close_ems_store (j_common_ptr cinfo, backing_store_ptr info)

+{

+  EMScontext ctx;

+

+  ctx.ax = 0x4500;

+  ctx.dx = info->handle.ems_handle;

+  jems_calldriver((EMScontext far *) & ctx);

+  TRACEMS1(cinfo, 1, JTRC_EMS_CLOSE, info->handle.ems_handle);

+  /* we ignore any error return from the driver */

+}

+

+

+LOCAL boolean

+open_ems_store (j_common_ptr cinfo, backing_store_ptr info,

+		long total_bytes_needed)

+{

+  EMScontext ctx;

+

+  /* Is EMS driver there? */

+  if (! jems_available())

+    return FALSE;

+

+  /* Get status, make sure EMS is OK */

+  ctx.ax = 0x4000;

+  jems_calldriver((EMScontext far *) & ctx);

+  if (HIBYTE(ctx.ax) != 0)

+    return FALSE;

+

+  /* Get version, must be >= 4.0 */

+  ctx.ax = 0x4600;

+  jems_calldriver((EMScontext far *) & ctx);

+  if (HIBYTE(ctx.ax) != 0 || LOBYTE(ctx.ax) < 0x40)

+    return FALSE;

+

+  /* Try to allocate requested space */

+  ctx.ax = 0x4300;

+  ctx.bx = (unsigned short) ((total_bytes_needed + EMSPAGESIZE-1L) / EMSPAGESIZE);

+  jems_calldriver((EMScontext far *) & ctx);

+  if (HIBYTE(ctx.ax) != 0)

+    return FALSE;

+

+  /* Succeeded, save the handle and away we go */

+  info->handle.ems_handle = ctx.dx;

+  info->read_backing_store = read_ems_store;

+  info->write_backing_store = write_ems_store;

+  info->close_backing_store = close_ems_store;

+  TRACEMS1(cinfo, 1, JTRC_EMS_OPEN, ctx.dx);

+  return TRUE;			/* succeeded */

+}

+

+#endif /* EMS_SUPPORTED */

+

+

+/*

+ * Initial opening of a backing-store object.

+ */

+

+GLOBAL void

+jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+			 long total_bytes_needed)

+{

+  /* Try extended memory, then expanded memory, then regular file. */

+#if XMS_SUPPORTED

+  if (open_xms_store(cinfo, info, total_bytes_needed))

+    return;

+#endif

+#if EMS_SUPPORTED

+  if (open_ems_store(cinfo, info, total_bytes_needed))

+    return;

+#endif

+  if (open_file_store(cinfo, info, total_bytes_needed))

+    return;

+  ERREXITS(cinfo, JERR_TFILE_CREATE, "");

+}

+

+

+/*

+ * These routines take care of any system-dependent initialization and

+ * cleanup required.

+ */

+

+GLOBAL long

+jpeg_mem_init (j_common_ptr cinfo)

+{

+  next_file_num = 0;		/* initialize temp file name generator */

+  return DEFAULT_MAX_MEM;	/* default for max_memory_to_use */

+}

+

+GLOBAL void

+jpeg_mem_term (j_common_ptr cinfo)

+{

+  /* Microsoft C, at least in v6.00A, will not successfully reclaim freed

+   * blocks of size > 32Kbytes unless we give it a kick in the rear, like so:

+   */

+#ifdef NEED_FHEAPMIN

+  _fheapmin();

+#endif

+}

diff --git a/code/jpeg-6/jmemmgr.c b/code/jpeg-6/jmemmgr.c
new file mode 100755
index 0000000..61045f9
--- /dev/null
+++ b/code/jpeg-6/jmemmgr.c
@@ -0,0 +1,1115 @@
+/*

+ * jmemmgr.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains the JPEG system-independent memory management

+ * routines.  This code is usable across a wide variety of machines; most

+ * of the system dependencies have been isolated in a separate file.

+ * The major functions provided here are:

+ *   * pool-based allocation and freeing of memory;

+ *   * policy decisions about how to divide available memory among the

+ *     virtual arrays;

+ *   * control logic for swapping virtual arrays between main memory and

+ *     backing storage.

+ * The separate system-dependent file provides the actual backing-storage

+ * access code, and it contains the policy decision about how much total

+ * main memory to use.

+ * This file is system-dependent in the sense that some of its functions

+ * are unnecessary in some systems.  For example, if there is enough virtual

+ * memory so that backing storage will never be used, much of the virtual

+ * array control logic could be removed.  (Of course, if you have that much

+ * memory then you shouldn't care about a little bit of unused code...)

+ */

+

+#define JPEG_INTERNALS

+#define AM_MEMORY_MANAGER	/* we define jvirt_Xarray_control structs */

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jmemsys.h"		/* import the system-dependent declarations */

+

+#ifndef NO_GETENV

+#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare getenv() */

+extern char * getenv JPP((const char * name));

+#endif

+#endif

+

+

+/*

+ * Some important notes:

+ *   The allocation routines provided here must never return NULL.

+ *   They should exit to error_exit if unsuccessful.

+ *

+ *   It's not a good idea to try to merge the sarray and barray routines,

+ *   even though they are textually almost the same, because samples are

+ *   usually stored as bytes while coefficients are shorts or ints.  Thus,

+ *   in machines where byte pointers have a different representation from

+ *   word pointers, the resulting machine code could not be the same.

+ */

+

+

+/*

+ * Many machines require storage alignment: longs must start on 4-byte

+ * boundaries, doubles on 8-byte boundaries, etc.  On such machines, malloc()

+ * always returns pointers that are multiples of the worst-case alignment

+ * requirement, and we had better do so too.

+ * There isn't any really portable way to determine the worst-case alignment

+ * requirement.  This module assumes that the alignment requirement is

+ * multiples of sizeof(ALIGN_TYPE).

+ * By default, we define ALIGN_TYPE as double.  This is necessary on some

+ * workstations (where doubles really do need 8-byte alignment) and will work

+ * fine on nearly everything.  If your machine has lesser alignment needs,

+ * you can save a few bytes by making ALIGN_TYPE smaller.

+ * The only place I know of where this will NOT work is certain Macintosh

+ * 680x0 compilers that define double as a 10-byte IEEE extended float.

+ * Doing 10-byte alignment is counterproductive because longwords won't be

+ * aligned well.  Put "#define ALIGN_TYPE long" in jconfig.h if you have

+ * such a compiler.

+ */

+

+#ifndef ALIGN_TYPE		/* so can override from jconfig.h */

+#define ALIGN_TYPE  double

+#endif

+

+

+/*

+ * We allocate objects from "pools", where each pool is gotten with a single

+ * request to jpeg_get_small() or jpeg_get_large().  There is no per-object

+ * overhead within a pool, except for alignment padding.  Each pool has a

+ * header with a link to the next pool of the same class.

+ * Small and large pool headers are identical except that the latter's

+ * link pointer must be FAR on 80x86 machines.

+ * Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE

+ * field.  This forces the compiler to make SIZEOF(small_pool_hdr) a multiple

+ * of the alignment requirement of ALIGN_TYPE.

+ */

+

+typedef union small_pool_struct * small_pool_ptr;

+

+typedef union small_pool_struct {

+  struct {

+    small_pool_ptr next;	/* next in list of pools */

+    size_t bytes_used;		/* how many bytes already used within pool */

+    size_t bytes_left;		/* bytes still available in this pool */

+  } hdr;

+  ALIGN_TYPE dummy;		/* included in union to ensure alignment */

+} small_pool_hdr;

+

+typedef union large_pool_struct FAR * large_pool_ptr;

+

+typedef union large_pool_struct {

+  struct {

+    large_pool_ptr next;	/* next in list of pools */

+    size_t bytes_used;		/* how many bytes already used within pool */

+    size_t bytes_left;		/* bytes still available in this pool */

+  } hdr;

+  ALIGN_TYPE dummy;		/* included in union to ensure alignment */

+} large_pool_hdr;

+

+

+/*

+ * Here is the full definition of a memory manager object.

+ */

+

+typedef struct {

+  struct jpeg_memory_mgr pub;	/* public fields */

+

+  /* Each pool identifier (lifetime class) names a linked list of pools. */

+  small_pool_ptr small_list[JPOOL_NUMPOOLS];

+  large_pool_ptr large_list[JPOOL_NUMPOOLS];

+

+  /* Since we only have one lifetime class of virtual arrays, only one

+   * linked list is necessary (for each datatype).  Note that the virtual

+   * array control blocks being linked together are actually stored somewhere

+   * in the small-pool list.

+   */

+  jvirt_sarray_ptr virt_sarray_list;

+  jvirt_barray_ptr virt_barray_list;

+

+  /* This counts total space obtained from jpeg_get_small/large */

+  long total_space_allocated;

+

+  /* alloc_sarray and alloc_barray set this value for use by virtual

+   * array routines.

+   */

+  JDIMENSION last_rowsperchunk;	/* from most recent alloc_sarray/barray */

+} my_memory_mgr;

+

+typedef my_memory_mgr * my_mem_ptr;

+

+

+/*

+ * The control blocks for virtual arrays.

+ * Note that these blocks are allocated in the "small" pool area.

+ * System-dependent info for the associated backing store (if any) is hidden

+ * inside the backing_store_info struct.

+ */

+

+struct jvirt_sarray_control {

+  JSAMPARRAY mem_buffer;	/* => the in-memory buffer */

+  JDIMENSION rows_in_array;	/* total virtual array height */

+  JDIMENSION samplesperrow;	/* width of array (and of memory buffer) */

+  JDIMENSION maxaccess;		/* max rows accessed by access_virt_sarray */

+  JDIMENSION rows_in_mem;	/* height of memory buffer */

+  JDIMENSION rowsperchunk;	/* allocation chunk size in mem_buffer */

+  JDIMENSION cur_start_row;	/* first logical row # in the buffer */

+  JDIMENSION first_undef_row;	/* row # of first uninitialized row */

+  boolean pre_zero;		/* pre-zero mode requested? */

+  boolean dirty;		/* do current buffer contents need written? */

+  boolean b_s_open;		/* is backing-store data valid? */

+  jvirt_sarray_ptr next;	/* link to next virtual sarray control block */

+  backing_store_info b_s_info;	/* System-dependent control info */

+};

+

+struct jvirt_barray_control {

+  JBLOCKARRAY mem_buffer;	/* => the in-memory buffer */

+  JDIMENSION rows_in_array;	/* total virtual array height */

+  JDIMENSION blocksperrow;	/* width of array (and of memory buffer) */

+  JDIMENSION maxaccess;		/* max rows accessed by access_virt_barray */

+  JDIMENSION rows_in_mem;	/* height of memory buffer */

+  JDIMENSION rowsperchunk;	/* allocation chunk size in mem_buffer */

+  JDIMENSION cur_start_row;	/* first logical row # in the buffer */

+  JDIMENSION first_undef_row;	/* row # of first uninitialized row */

+  boolean pre_zero;		/* pre-zero mode requested? */

+  boolean dirty;		/* do current buffer contents need written? */

+  boolean b_s_open;		/* is backing-store data valid? */

+  jvirt_barray_ptr next;	/* link to next virtual barray control block */

+  backing_store_info b_s_info;	/* System-dependent control info */

+};

+

+

+#ifdef MEM_STATS		/* optional extra stuff for statistics */

+

+LOCAL void

+print_mem_stats (j_common_ptr cinfo, int pool_id)

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  small_pool_ptr shdr_ptr;

+  large_pool_ptr lhdr_ptr;

+

+  /* Since this is only a debugging stub, we can cheat a little by using

+   * fprintf directly rather than going through the trace message code.

+   * This is helpful because message parm array can't handle longs.

+   */

+  fprintf(stderr, "Freeing pool %d, total space = %ld\n",

+	  pool_id, mem->total_space_allocated);

+

+  for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL;

+       lhdr_ptr = lhdr_ptr->hdr.next) {

+    fprintf(stderr, "  Large chunk used %ld\n",

+	    (long) lhdr_ptr->hdr.bytes_used);

+  }

+

+  for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL;

+       shdr_ptr = shdr_ptr->hdr.next) {

+    fprintf(stderr, "  Small chunk used %ld free %ld\n",

+	    (long) shdr_ptr->hdr.bytes_used,

+	    (long) shdr_ptr->hdr.bytes_left);

+  }

+}

+

+#endif /* MEM_STATS */

+

+

+LOCAL void

+out_of_memory (j_common_ptr cinfo, int which)

+/* Report an out-of-memory error and stop execution */

+/* If we compiled MEM_STATS support, report alloc requests before dying */

+{

+#ifdef MEM_STATS

+  cinfo->err->trace_level = 2;	/* force self_destruct to report stats */

+#endif

+  ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which);

+}

+

+

+/*

+ * Allocation of "small" objects.

+ *

+ * For these, we use pooled storage.  When a new pool must be created,

+ * we try to get enough space for the current request plus a "slop" factor,

+ * where the slop will be the amount of leftover space in the new pool.

+ * The speed vs. space tradeoff is largely determined by the slop values.

+ * A different slop value is provided for each pool class (lifetime),

+ * and we also distinguish the first pool of a class from later ones.

+ * NOTE: the values given work fairly well on both 16- and 32-bit-int

+ * machines, but may be too small if longs are 64 bits or more.

+ */

+

+static const size_t first_pool_slop[JPOOL_NUMPOOLS] = 

+{

+	1600,			/* first PERMANENT pool */

+	16000			/* first IMAGE pool */

+};

+

+static const size_t extra_pool_slop[JPOOL_NUMPOOLS] = 

+{

+	0,			/* additional PERMANENT pools */

+	5000			/* additional IMAGE pools */

+};

+

+#define MIN_SLOP  50		/* greater than 0 to avoid futile looping */

+

+

+METHODDEF void *

+alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject)

+/* Allocate a "small" object */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  small_pool_ptr hdr_ptr, prev_hdr_ptr;

+  char * data_ptr;

+  size_t odd_bytes, min_request, slop;

+

+  /* Check for unsatisfiable request (do now to ensure no overflow below) */

+  if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(small_pool_hdr)))

+    out_of_memory(cinfo, 1);	/* request exceeds malloc's ability */

+

+  /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */

+  odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);

+  if (odd_bytes > 0)

+    sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;

+

+  /* See if space is available in any existing pool */

+  if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)

+    ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id);	/* safety check */

+  prev_hdr_ptr = NULL;

+  hdr_ptr = mem->small_list[pool_id];

+  while (hdr_ptr != NULL) {

+    if (hdr_ptr->hdr.bytes_left >= sizeofobject)

+      break;			/* found pool with enough space */

+    prev_hdr_ptr = hdr_ptr;

+    hdr_ptr = hdr_ptr->hdr.next;

+  }

+

+  /* Time to make a new pool? */

+  if (hdr_ptr == NULL) {

+    /* min_request is what we need now, slop is what will be leftover */

+    min_request = sizeofobject + SIZEOF(small_pool_hdr);

+    if (prev_hdr_ptr == NULL)	/* first pool in class? */

+      slop = first_pool_slop[pool_id];

+    else

+      slop = extra_pool_slop[pool_id];

+    /* Don't ask for more than MAX_ALLOC_CHUNK */

+    if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request))

+      slop = (size_t) (MAX_ALLOC_CHUNK-min_request);

+    /* Try to get space, if fail reduce slop and try again */

+    for (;;) {

+      hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop);

+      if (hdr_ptr != NULL)

+	break;

+      slop /= 2;

+      if (slop < MIN_SLOP)	/* give up when it gets real small */

+	out_of_memory(cinfo, 2); /* jpeg_get_small failed */

+    }

+    mem->total_space_allocated += min_request + slop;

+    /* Success, initialize the new pool header and add to end of list */

+    hdr_ptr->hdr.next = NULL;

+    hdr_ptr->hdr.bytes_used = 0;

+    hdr_ptr->hdr.bytes_left = sizeofobject + slop;

+    if (prev_hdr_ptr == NULL)	/* first pool in class? */

+      mem->small_list[pool_id] = hdr_ptr;

+    else

+      prev_hdr_ptr->hdr.next = hdr_ptr;

+  }

+

+  /* OK, allocate the object from the current pool */

+  data_ptr = (char *) (hdr_ptr + 1); /* point to first data byte in pool */

+  data_ptr += hdr_ptr->hdr.bytes_used; /* point to place for object */

+  hdr_ptr->hdr.bytes_used += sizeofobject;

+  hdr_ptr->hdr.bytes_left -= sizeofobject;

+

+  return (void *) data_ptr;

+}

+

+

+/*

+ * Allocation of "large" objects.

+ *

+ * The external semantics of these are the same as "small" objects,

+ * except that FAR pointers are used on 80x86.  However the pool

+ * management heuristics are quite different.  We assume that each

+ * request is large enough that it may as well be passed directly to

+ * jpeg_get_large; the pool management just links everything together

+ * so that we can free it all on demand.

+ * Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY

+ * structures.  The routines that create these structures (see below)

+ * deliberately bunch rows together to ensure a large request size.

+ */

+

+METHODDEF void FAR *

+alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject)

+/* Allocate a "large" object */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  large_pool_ptr hdr_ptr;

+  size_t odd_bytes;

+

+  /* Check for unsatisfiable request (do now to ensure no overflow below) */

+  if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)))

+    out_of_memory(cinfo, 3);	/* request exceeds malloc's ability */

+

+  /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */

+  odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);

+  if (odd_bytes > 0)

+    sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;

+

+  /* Always make a new pool */

+  if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)

+    ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id);	/* safety check */

+

+  hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject +

+					    SIZEOF(large_pool_hdr));

+  if (hdr_ptr == NULL)

+    out_of_memory(cinfo, 4);	/* jpeg_get_large failed */

+  mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr);

+

+  /* Success, initialize the new pool header and add to list */

+  hdr_ptr->hdr.next = mem->large_list[pool_id];

+  /* We maintain space counts in each pool header for statistical purposes,

+   * even though they are not needed for allocation.

+   */

+  hdr_ptr->hdr.bytes_used = sizeofobject;

+  hdr_ptr->hdr.bytes_left = 0;

+  mem->large_list[pool_id] = hdr_ptr;

+

+  return (void FAR *) (hdr_ptr + 1); /* point to first data byte in pool */

+}

+

+

+/*

+ * Creation of 2-D sample arrays.

+ * The pointers are in near heap, the samples themselves in FAR heap.

+ *

+ * To minimize allocation overhead and to allow I/O of large contiguous

+ * blocks, we allocate the sample rows in groups of as many rows as possible

+ * without exceeding MAX_ALLOC_CHUNK total bytes per allocation request.

+ * NB: the virtual array control routines, later in this file, know about

+ * this chunking of rows.  The rowsperchunk value is left in the mem manager

+ * object so that it can be saved away if this sarray is the workspace for

+ * a virtual array.

+ */

+

+METHODDEF JSAMPARRAY

+alloc_sarray (j_common_ptr cinfo, int pool_id,

+	      JDIMENSION samplesperrow, JDIMENSION numrows)

+/* Allocate a 2-D sample array */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  JSAMPARRAY result;

+  JSAMPROW workspace;

+  JDIMENSION rowsperchunk, currow, i;

+  long ltemp;

+

+  /* Calculate max # of rows allowed in one allocation chunk */

+  ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /

+	  ((long) samplesperrow * SIZEOF(JSAMPLE));

+  if (ltemp <= 0)

+    ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);

+  if (ltemp < (long) numrows)

+    rowsperchunk = (JDIMENSION) ltemp;

+  else

+    rowsperchunk = numrows;

+  mem->last_rowsperchunk = rowsperchunk;

+

+  /* Get space for row pointers (small object) */

+  result = (JSAMPARRAY) alloc_small(cinfo, pool_id,

+				    (size_t) (numrows * SIZEOF(JSAMPROW)));

+

+  /* Get the rows themselves (large objects) */

+  currow = 0;

+  while (currow < numrows) {

+    rowsperchunk = MIN(rowsperchunk, numrows - currow);

+    workspace = (JSAMPROW) alloc_large(cinfo, pool_id,

+	(size_t) ((size_t) rowsperchunk * (size_t) samplesperrow

+		  * SIZEOF(JSAMPLE)));

+    for (i = rowsperchunk; i > 0; i--) {

+      result[currow++] = workspace;

+      workspace += samplesperrow;

+    }

+  }

+

+  return result;

+}

+

+

+/*

+ * Creation of 2-D coefficient-block arrays.

+ * This is essentially the same as the code for sample arrays, above.

+ */

+

+METHODDEF JBLOCKARRAY

+alloc_barray (j_common_ptr cinfo, int pool_id,

+	      JDIMENSION blocksperrow, JDIMENSION numrows)

+/* Allocate a 2-D coefficient-block array */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  JBLOCKARRAY result;

+  JBLOCKROW workspace;

+  JDIMENSION rowsperchunk, currow, i;

+  long ltemp;

+

+  /* Calculate max # of rows allowed in one allocation chunk */

+  ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /

+	  ((long) blocksperrow * SIZEOF(JBLOCK));

+  if (ltemp <= 0)

+    ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);

+  if (ltemp < (long) numrows)

+    rowsperchunk = (JDIMENSION) ltemp;

+  else

+    rowsperchunk = numrows;

+  mem->last_rowsperchunk = rowsperchunk;

+

+  /* Get space for row pointers (small object) */

+  result = (JBLOCKARRAY) alloc_small(cinfo, pool_id,

+				     (size_t) (numrows * SIZEOF(JBLOCKROW)));

+

+  /* Get the rows themselves (large objects) */

+  currow = 0;

+  while (currow < numrows) {

+    rowsperchunk = MIN(rowsperchunk, numrows - currow);

+    workspace = (JBLOCKROW) alloc_large(cinfo, pool_id,

+	(size_t) ((size_t) rowsperchunk * (size_t) blocksperrow

+		  * SIZEOF(JBLOCK)));

+    for (i = rowsperchunk; i > 0; i--) {

+      result[currow++] = workspace;

+      workspace += blocksperrow;

+    }

+  }

+

+  return result;

+}

+

+

+/*

+ * About virtual array management:

+ *

+ * The above "normal" array routines are only used to allocate strip buffers

+ * (as wide as the image, but just a few rows high).  Full-image-sized buffers

+ * are handled as "virtual" arrays.  The array is still accessed a strip at a

+ * time, but the memory manager must save the whole array for repeated

+ * accesses.  The intended implementation is that there is a strip buffer in

+ * memory (as high as is possible given the desired memory limit), plus a

+ * backing file that holds the rest of the array.

+ *

+ * The request_virt_array routines are told the total size of the image and

+ * the maximum number of rows that will be accessed at once.  The in-memory

+ * buffer must be at least as large as the maxaccess value.

+ *

+ * The request routines create control blocks but not the in-memory buffers.

+ * That is postponed until realize_virt_arrays is called.  At that time the

+ * total amount of space needed is known (approximately, anyway), so free

+ * memory can be divided up fairly.

+ *

+ * The access_virt_array routines are responsible for making a specific strip

+ * area accessible (after reading or writing the backing file, if necessary).

+ * Note that the access routines are told whether the caller intends to modify

+ * the accessed strip; during a read-only pass this saves having to rewrite

+ * data to disk.  The access routines are also responsible for pre-zeroing

+ * any newly accessed rows, if pre-zeroing was requested.

+ *

+ * In current usage, the access requests are usually for nonoverlapping

+ * strips; that is, successive access start_row numbers differ by exactly

+ * num_rows = maxaccess.  This means we can get good performance with simple

+ * buffer dump/reload logic, by making the in-memory buffer be a multiple

+ * of the access height; then there will never be accesses across bufferload

+ * boundaries.  The code will still work with overlapping access requests,

+ * but it doesn't handle bufferload overlaps very efficiently.

+ */

+

+

+METHODDEF jvirt_sarray_ptr

+request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero,

+		     JDIMENSION samplesperrow, JDIMENSION numrows,

+		     JDIMENSION maxaccess)

+/* Request a virtual 2-D sample array */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  jvirt_sarray_ptr result;

+

+  /* Only IMAGE-lifetime virtual arrays are currently supported */

+  if (pool_id != JPOOL_IMAGE)

+    ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id);	/* safety check */

+

+  /* get control block */

+  result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id,

+					  SIZEOF(struct jvirt_sarray_control));

+

+  result->mem_buffer = NULL;	/* marks array not yet realized */

+  result->rows_in_array = numrows;

+  result->samplesperrow = samplesperrow;

+  result->maxaccess = maxaccess;

+  result->pre_zero = pre_zero;

+  result->b_s_open = FALSE;	/* no associated backing-store object */

+  result->next = mem->virt_sarray_list; /* add to list of virtual arrays */

+  mem->virt_sarray_list = result;

+

+  return result;

+}

+

+

+METHODDEF jvirt_barray_ptr

+request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero,

+		     JDIMENSION blocksperrow, JDIMENSION numrows,

+		     JDIMENSION maxaccess)

+/* Request a virtual 2-D coefficient-block array */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  jvirt_barray_ptr result;

+

+  /* Only IMAGE-lifetime virtual arrays are currently supported */

+  if (pool_id != JPOOL_IMAGE)

+    ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id);	/* safety check */

+

+  /* get control block */

+  result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id,

+					  SIZEOF(struct jvirt_barray_control));

+

+  result->mem_buffer = NULL;	/* marks array not yet realized */

+  result->rows_in_array = numrows;

+  result->blocksperrow = blocksperrow;

+  result->maxaccess = maxaccess;

+  result->pre_zero = pre_zero;

+  result->b_s_open = FALSE;	/* no associated backing-store object */

+  result->next = mem->virt_barray_list; /* add to list of virtual arrays */

+  mem->virt_barray_list = result;

+

+  return result;

+}

+

+

+METHODDEF void

+realize_virt_arrays (j_common_ptr cinfo)

+/* Allocate the in-memory buffers for any unrealized virtual arrays */

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  long space_per_minheight, maximum_space, avail_mem;

+  long minheights, max_minheights;

+  jvirt_sarray_ptr sptr;

+  jvirt_barray_ptr bptr;

+

+  /* Compute the minimum space needed (maxaccess rows in each buffer)

+   * and the maximum space needed (full image height in each buffer).

+   * These may be of use to the system-dependent jpeg_mem_available routine.

+   */

+  space_per_minheight = 0;

+  maximum_space = 0;

+  for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {

+    if (sptr->mem_buffer == NULL) { /* if not realized yet */

+      space_per_minheight += (long) sptr->maxaccess *

+			     (long) sptr->samplesperrow * SIZEOF(JSAMPLE);

+      maximum_space += (long) sptr->rows_in_array *

+		       (long) sptr->samplesperrow * SIZEOF(JSAMPLE);

+    }

+  }

+  for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {

+    if (bptr->mem_buffer == NULL) { /* if not realized yet */

+      space_per_minheight += (long) bptr->maxaccess *

+			     (long) bptr->blocksperrow * SIZEOF(JBLOCK);

+      maximum_space += (long) bptr->rows_in_array *

+		       (long) bptr->blocksperrow * SIZEOF(JBLOCK);

+    }

+  }

+

+  if (space_per_minheight <= 0)

+    return;			/* no unrealized arrays, no work */

+

+  /* Determine amount of memory to actually use; this is system-dependent. */

+  avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space,

+				 mem->total_space_allocated);

+

+  /* If the maximum space needed is available, make all the buffers full

+   * height; otherwise parcel it out with the same number of minheights

+   * in each buffer.

+   */

+  if (avail_mem >= maximum_space)

+    max_minheights = 1000000000L;

+  else {

+    max_minheights = avail_mem / space_per_minheight;

+    /* If there doesn't seem to be enough space, try to get the minimum

+     * anyway.  This allows a "stub" implementation of jpeg_mem_available().

+     */

+    if (max_minheights <= 0)

+      max_minheights = 1;

+  }

+

+  /* Allocate the in-memory buffers and initialize backing store as needed. */

+

+  for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {

+    if (sptr->mem_buffer == NULL) { /* if not realized yet */

+      minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L;

+      if (minheights <= max_minheights) {

+	/* This buffer fits in memory */

+	sptr->rows_in_mem = sptr->rows_in_array;

+      } else {

+	/* It doesn't fit in memory, create backing store. */

+	sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess);

+	jpeg_open_backing_store(cinfo, & sptr->b_s_info,

+				(long) sptr->rows_in_array *

+				(long) sptr->samplesperrow *

+				(long) SIZEOF(JSAMPLE));

+	sptr->b_s_open = TRUE;

+      }

+      sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE,

+				      sptr->samplesperrow, sptr->rows_in_mem);

+      sptr->rowsperchunk = mem->last_rowsperchunk;

+      sptr->cur_start_row = 0;

+      sptr->first_undef_row = 0;

+      sptr->dirty = FALSE;

+    }

+  }

+

+  for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {

+    if (bptr->mem_buffer == NULL) { /* if not realized yet */

+      minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L;

+      if (minheights <= max_minheights) {

+	/* This buffer fits in memory */

+	bptr->rows_in_mem = bptr->rows_in_array;

+      } else {

+	/* It doesn't fit in memory, create backing store. */

+	bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess);

+	jpeg_open_backing_store(cinfo, & bptr->b_s_info,

+				(long) bptr->rows_in_array *

+				(long) bptr->blocksperrow *

+				(long) SIZEOF(JBLOCK));

+	bptr->b_s_open = TRUE;

+      }

+      bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE,

+				      bptr->blocksperrow, bptr->rows_in_mem);

+      bptr->rowsperchunk = mem->last_rowsperchunk;

+      bptr->cur_start_row = 0;

+      bptr->first_undef_row = 0;

+      bptr->dirty = FALSE;

+    }

+  }

+}

+

+

+LOCAL void

+do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing)

+/* Do backing store read or write of a virtual sample array */

+{

+  long bytesperrow, file_offset, byte_count, rows, thisrow, i;

+

+  bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE);

+  file_offset = ptr->cur_start_row * bytesperrow;

+  /* Loop to read or write each allocation chunk in mem_buffer */

+  for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {

+    /* One chunk, but check for short chunk at end of buffer */

+    rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);

+    /* Transfer no more than is currently defined */

+    thisrow = (long) ptr->cur_start_row + i;

+    rows = MIN(rows, (long) ptr->first_undef_row - thisrow);

+    /* Transfer no more than fits in file */

+    rows = MIN(rows, (long) ptr->rows_in_array - thisrow);

+    if (rows <= 0)		/* this chunk might be past end of file! */

+      break;

+    byte_count = rows * bytesperrow;

+    if (writing)

+      (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,

+					    (void FAR *) ptr->mem_buffer[i],

+					    file_offset, byte_count);

+    else

+      (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,

+					   (void FAR *) ptr->mem_buffer[i],

+					   file_offset, byte_count);

+    file_offset += byte_count;

+  }

+}

+

+

+LOCAL void

+do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing)

+/* Do backing store read or write of a virtual coefficient-block array */

+{

+  long bytesperrow, file_offset, byte_count, rows, thisrow, i;

+

+  bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK);

+  file_offset = ptr->cur_start_row * bytesperrow;

+  /* Loop to read or write each allocation chunk in mem_buffer */

+  for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {

+    /* One chunk, but check for short chunk at end of buffer */

+    rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);

+    /* Transfer no more than is currently defined */

+    thisrow = (long) ptr->cur_start_row + i;

+    rows = MIN(rows, (long) ptr->first_undef_row - thisrow);

+    /* Transfer no more than fits in file */

+    rows = MIN(rows, (long) ptr->rows_in_array - thisrow);

+    if (rows <= 0)		/* this chunk might be past end of file! */

+      break;

+    byte_count = rows * bytesperrow;

+    if (writing)

+      (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,

+					    (void FAR *) ptr->mem_buffer[i],

+					    file_offset, byte_count);

+    else

+      (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,

+					   (void FAR *) ptr->mem_buffer[i],

+					   file_offset, byte_count);

+    file_offset += byte_count;

+  }

+}

+

+

+METHODDEF JSAMPARRAY

+access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr,

+		    JDIMENSION start_row, JDIMENSION num_rows,

+		    boolean writable)

+/* Access the part of a virtual sample array starting at start_row */

+/* and extending for num_rows rows.  writable is true if  */

+/* caller intends to modify the accessed area. */

+{

+  JDIMENSION end_row = start_row + num_rows;

+  JDIMENSION undef_row;

+

+  /* debugging check */

+  if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||

+      ptr->mem_buffer == NULL)

+    ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+

+  /* Make the desired part of the virtual array accessible */

+  if (start_row < ptr->cur_start_row ||

+      end_row > ptr->cur_start_row+ptr->rows_in_mem) {

+    if (! ptr->b_s_open)

+      ERREXIT(cinfo, JERR_VIRTUAL_BUG);

+    /* Flush old buffer contents if necessary */

+    if (ptr->dirty) {

+      do_sarray_io(cinfo, ptr, TRUE);

+      ptr->dirty = FALSE;

+    }

+    /* Decide what part of virtual array to access.

+     * Algorithm: if target address > current window, assume forward scan,

+     * load starting at target address.  If target address < current window,

+     * assume backward scan, load so that target area is top of window.

+     * Note that when switching from forward write to forward read, will have

+     * start_row = 0, so the limiting case applies and we load from 0 anyway.

+     */

+    if (start_row > ptr->cur_start_row) {

+      ptr->cur_start_row = start_row;

+    } else {

+      /* use long arithmetic here to avoid overflow & unsigned problems */

+      long ltemp;

+

+      ltemp = (long) end_row - (long) ptr->rows_in_mem;

+      if (ltemp < 0)

+	ltemp = 0;		/* don't fall off front end of file */

+      ptr->cur_start_row = (JDIMENSION) ltemp;

+    }

+    /* Read in the selected part of the array.

+     * During the initial write pass, we will do no actual read

+     * because the selected part is all undefined.

+     */

+    do_sarray_io(cinfo, ptr, FALSE);

+  }

+  /* Ensure the accessed part of the array is defined; prezero if needed.

+   * To improve locality of access, we only prezero the part of the array

+   * that the caller is about to access, not the entire in-memory array.

+   */

+  if (ptr->first_undef_row < end_row) {

+    if (ptr->first_undef_row < start_row) {

+      if (writable)		/* writer skipped over a section of array */

+	ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+      undef_row = start_row;	/* but reader is allowed to read ahead */

+    } else {

+      undef_row = ptr->first_undef_row;

+    }

+    if (writable)

+      ptr->first_undef_row = end_row;

+    if (ptr->pre_zero) {

+      size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE);

+      undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */

+      end_row -= ptr->cur_start_row;

+      while (undef_row < end_row) {

+	jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);

+	undef_row++;

+      }

+    } else {

+      if (! writable)		/* reader looking at undefined data */

+	ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+    }

+  }

+  /* Flag the buffer dirty if caller will write in it */

+  if (writable)

+    ptr->dirty = TRUE;

+  /* Return address of proper part of the buffer */

+  return ptr->mem_buffer + (start_row - ptr->cur_start_row);

+}

+

+

+METHODDEF JBLOCKARRAY

+access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr,

+		    JDIMENSION start_row, JDIMENSION num_rows,

+		    boolean writable)

+/* Access the part of a virtual block array starting at start_row */

+/* and extending for num_rows rows.  writable is true if  */

+/* caller intends to modify the accessed area. */

+{

+  JDIMENSION end_row = start_row + num_rows;

+  JDIMENSION undef_row;

+

+  /* debugging check */

+  if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||

+      ptr->mem_buffer == NULL)

+    ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+

+  /* Make the desired part of the virtual array accessible */

+  if (start_row < ptr->cur_start_row ||

+      end_row > ptr->cur_start_row+ptr->rows_in_mem) {

+    if (! ptr->b_s_open)

+      ERREXIT(cinfo, JERR_VIRTUAL_BUG);

+    /* Flush old buffer contents if necessary */

+    if (ptr->dirty) {

+      do_barray_io(cinfo, ptr, TRUE);

+      ptr->dirty = FALSE;

+    }

+    /* Decide what part of virtual array to access.

+     * Algorithm: if target address > current window, assume forward scan,

+     * load starting at target address.  If target address < current window,

+     * assume backward scan, load so that target area is top of window.

+     * Note that when switching from forward write to forward read, will have

+     * start_row = 0, so the limiting case applies and we load from 0 anyway.

+     */

+    if (start_row > ptr->cur_start_row) {

+      ptr->cur_start_row = start_row;

+    } else {

+      /* use long arithmetic here to avoid overflow & unsigned problems */

+      long ltemp;

+

+      ltemp = (long) end_row - (long) ptr->rows_in_mem;

+      if (ltemp < 0)

+	ltemp = 0;		/* don't fall off front end of file */

+      ptr->cur_start_row = (JDIMENSION) ltemp;

+    }

+    /* Read in the selected part of the array.

+     * During the initial write pass, we will do no actual read

+     * because the selected part is all undefined.

+     */

+    do_barray_io(cinfo, ptr, FALSE);

+  }

+  /* Ensure the accessed part of the array is defined; prezero if needed.

+   * To improve locality of access, we only prezero the part of the array

+   * that the caller is about to access, not the entire in-memory array.

+   */

+  if (ptr->first_undef_row < end_row) {

+    if (ptr->first_undef_row < start_row) {

+      if (writable)		/* writer skipped over a section of array */

+	ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+      undef_row = start_row;	/* but reader is allowed to read ahead */

+    } else {

+      undef_row = ptr->first_undef_row;

+    }

+    if (writable)

+      ptr->first_undef_row = end_row;

+    if (ptr->pre_zero) {

+      size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK);

+      undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */

+      end_row -= ptr->cur_start_row;

+      while (undef_row < end_row) {

+	jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);

+	undef_row++;

+      }

+    } else {

+      if (! writable)		/* reader looking at undefined data */

+	ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);

+    }

+  }

+  /* Flag the buffer dirty if caller will write in it */

+  if (writable)

+    ptr->dirty = TRUE;

+  /* Return address of proper part of the buffer */

+  return ptr->mem_buffer + (start_row - ptr->cur_start_row);

+}

+

+

+/*

+ * Release all objects belonging to a specified pool.

+ */

+

+METHODDEF void

+free_pool (j_common_ptr cinfo, int pool_id)

+{

+  my_mem_ptr mem = (my_mem_ptr) cinfo->mem;

+  small_pool_ptr shdr_ptr;

+  large_pool_ptr lhdr_ptr;

+  size_t space_freed;

+

+  if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)

+    ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id);	/* safety check */

+

+#ifdef MEM_STATS

+  if (cinfo->err->trace_level > 1)

+    print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */

+#endif

+

+  /* If freeing IMAGE pool, close any virtual arrays first */

+  if (pool_id == JPOOL_IMAGE) {

+    jvirt_sarray_ptr sptr;

+    jvirt_barray_ptr bptr;

+

+    for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {

+      if (sptr->b_s_open) {	/* there may be no backing store */

+	sptr->b_s_open = FALSE;	/* prevent recursive close if error */

+	(*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info);

+      }

+    }

+    mem->virt_sarray_list = NULL;

+    for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {

+      if (bptr->b_s_open) {	/* there may be no backing store */

+	bptr->b_s_open = FALSE;	/* prevent recursive close if error */

+	(*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info);

+      }

+    }

+    mem->virt_barray_list = NULL;

+  }

+

+  /* Release large objects */

+  lhdr_ptr = mem->large_list[pool_id];

+  mem->large_list[pool_id] = NULL;

+

+  while (lhdr_ptr != NULL) {

+    large_pool_ptr next_lhdr_ptr = lhdr_ptr->hdr.next;

+    space_freed = lhdr_ptr->hdr.bytes_used +

+		  lhdr_ptr->hdr.bytes_left +

+		  SIZEOF(large_pool_hdr);

+    jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed);

+    mem->total_space_allocated -= space_freed;

+    lhdr_ptr = next_lhdr_ptr;

+  }

+

+  /* Release small objects */

+  shdr_ptr = mem->small_list[pool_id];

+  mem->small_list[pool_id] = NULL;

+

+  while (shdr_ptr != NULL) {

+    small_pool_ptr next_shdr_ptr = shdr_ptr->hdr.next;

+    space_freed = shdr_ptr->hdr.bytes_used +

+		  shdr_ptr->hdr.bytes_left +

+		  SIZEOF(small_pool_hdr);

+    jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed);

+    mem->total_space_allocated -= space_freed;

+    shdr_ptr = next_shdr_ptr;

+  }

+}

+

+

+/*

+ * Close up shop entirely.

+ * Note that this cannot be called unless cinfo->mem is non-NULL.

+ */

+

+METHODDEF void

+self_destruct (j_common_ptr cinfo)

+{

+  int pool;

+

+  /* Close all backing store, release all memory.

+   * Releasing pools in reverse order might help avoid fragmentation

+   * with some (brain-damaged) malloc libraries.

+   */

+  for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {

+    free_pool(cinfo, pool);

+  }

+

+  /* Release the memory manager control block too. */

+  jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr));

+  cinfo->mem = NULL;		/* ensures I will be called only once */

+

+  jpeg_mem_term(cinfo);		/* system-dependent cleanup */

+}

+

+

+/*

+ * Memory manager initialization.

+ * When this is called, only the error manager pointer is valid in cinfo!

+ */

+

+GLOBAL void

+jinit_memory_mgr (j_common_ptr cinfo)

+{

+  my_mem_ptr mem;

+  long max_to_use;

+  int pool;

+  size_t test_mac;

+

+  cinfo->mem = NULL;		/* for safety if init fails */

+

+  /* Check for configuration errors.

+   * SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably

+   * doesn't reflect any real hardware alignment requirement.

+   * The test is a little tricky: for X>0, X and X-1 have no one-bits

+   * in common if and only if X is a power of 2, ie has only one one-bit.

+   * Some compilers may give an "unreachable code" warning here; ignore it.

+   */

+  if ((SIZEOF(ALIGN_TYPE) & (SIZEOF(ALIGN_TYPE)-1)) != 0)

+    ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE);

+  /* MAX_ALLOC_CHUNK must be representable as type size_t, and must be

+   * a multiple of SIZEOF(ALIGN_TYPE).

+   * Again, an "unreachable code" warning may be ignored here.

+   * But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK.

+   */

+  test_mac = (size_t) MAX_ALLOC_CHUNK;

+  if ((long) test_mac != MAX_ALLOC_CHUNK ||

+      (MAX_ALLOC_CHUNK % SIZEOF(ALIGN_TYPE)) != 0)

+    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);

+

+  max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */

+

+  /* Attempt to allocate memory manager's control block */

+  mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr));

+

+  if (mem == NULL) {

+    jpeg_mem_term(cinfo);	/* system-dependent cleanup */

+    ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0);

+  }

+

+  /* OK, fill in the method pointers */

+  mem->pub.alloc_small = alloc_small;

+  mem->pub.alloc_large = alloc_large;

+  mem->pub.alloc_sarray = alloc_sarray;

+  mem->pub.alloc_barray = alloc_barray;

+  mem->pub.request_virt_sarray = request_virt_sarray;

+  mem->pub.request_virt_barray = request_virt_barray;

+  mem->pub.realize_virt_arrays = realize_virt_arrays;

+  mem->pub.access_virt_sarray = access_virt_sarray;

+  mem->pub.access_virt_barray = access_virt_barray;

+  mem->pub.free_pool = free_pool;

+  mem->pub.self_destruct = self_destruct;

+

+  /* Initialize working state */

+  mem->pub.max_memory_to_use = max_to_use;

+

+  for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {

+    mem->small_list[pool] = NULL;

+    mem->large_list[pool] = NULL;

+  }

+  mem->virt_sarray_list = NULL;

+  mem->virt_barray_list = NULL;

+

+  mem->total_space_allocated = SIZEOF(my_memory_mgr);

+

+  /* Declare ourselves open for business */

+  cinfo->mem = & mem->pub;

+

+  /* Check for an environment variable JPEGMEM; if found, override the

+   * default max_memory setting from jpeg_mem_init.  Note that the

+   * surrounding application may again override this value.

+   * If your system doesn't support getenv(), define NO_GETENV to disable

+   * this feature.

+   */

+#ifndef NO_GETENV

+  { char * memenv;

+

+    if ((memenv = getenv("JPEGMEM")) != NULL) {

+      char ch = 'x';

+

+      if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) {

+	if (ch == 'm' || ch == 'M')

+	  max_to_use *= 1000L;

+	mem->pub.max_memory_to_use = max_to_use * 1000L;

+      }

+    }

+  }

+#endif

+

+}

diff --git a/code/jpeg-6/jmemname.c b/code/jpeg-6/jmemname.c
new file mode 100755
index 0000000..a3f6494
--- /dev/null
+++ b/code/jpeg-6/jmemname.c
@@ -0,0 +1,271 @@
+/*

+ * jmemname.c

+ *

+ * Copyright (C) 1992-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file provides a generic implementation of the system-dependent

+ * portion of the JPEG memory manager.  This implementation assumes that

+ * you must explicitly construct a name for each temp file.

+ * Also, the problem of determining the amount of memory available

+ * is shoved onto the user.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jmemsys.h"		/* import the system-dependent declarations */

+

+#ifndef HAVE_STDLIB_H		/* <stdlib.h> should declare malloc(),free() */

+extern void * malloc JPP((size_t size));

+extern void free JPP((void *ptr));

+#endif

+

+#ifndef SEEK_SET		/* pre-ANSI systems may not define this; */

+#define SEEK_SET  0		/* if not, assume 0 is correct */

+#endif

+

+#ifdef DONT_USE_B_MODE		/* define mode parameters for fopen() */

+#define READ_BINARY	"r"

+#define RW_BINARY	"w+"

+#else

+#define READ_BINARY	"rb"

+#define RW_BINARY	"w+b"

+#endif

+

+

+/*

+ * Selection of a file name for a temporary file.

+ * This is system-dependent!

+ *

+ * The code as given is suitable for most Unix systems, and it is easily

+ * modified for most non-Unix systems.  Some notes:

+ *  1.  The temp file is created in the directory named by TEMP_DIRECTORY.

+ *      The default value is /usr/tmp, which is the conventional place for

+ *      creating large temp files on Unix.  On other systems you'll probably

+ *      want to change the file location.  You can do this by editing the

+ *      #define, or (preferred) by defining TEMP_DIRECTORY in jconfig.h.

+ *

+ *  2.  If you need to change the file name as well as its location,

+ *      you can override the TEMP_FILE_NAME macro.  (Note that this is

+ *      actually a printf format string; it must contain %s and %d.)

+ *      Few people should need to do this.

+ *

+ *  3.  mktemp() is used to ensure that multiple processes running

+ *      simultaneously won't select the same file names.  If your system

+ *      doesn't have mktemp(), define NO_MKTEMP to do it the hard way.

+ *      (If you don't have <errno.h>, also define NO_ERRNO_H.)

+ *

+ *  4.  You probably want to define NEED_SIGNAL_CATCHER so that cjpeg.c/djpeg.c

+ *      will cause the temp files to be removed if you stop the program early.

+ */

+

+#ifndef TEMP_DIRECTORY		/* can override from jconfig.h or Makefile */

+#define TEMP_DIRECTORY  "/usr/tmp/" /* recommended setting for Unix */

+#endif

+

+static int next_file_num;	/* to distinguish among several temp files */

+

+#ifdef NO_MKTEMP

+

+#ifndef TEMP_FILE_NAME		/* can override from jconfig.h or Makefile */

+#define TEMP_FILE_NAME  "%sJPG%03d.TMP"

+#endif

+

+#ifndef NO_ERRNO_H

+#include <errno.h>		/* to define ENOENT */

+#endif

+

+/* ANSI C specifies that errno is a macro, but on older systems it's more

+ * likely to be a plain int variable.  And not all versions of errno.h

+ * bother to declare it, so we have to in order to be most portable.  Thus:

+ */

+#ifndef errno

+extern int errno;

+#endif

+

+

+LOCAL void

+select_file_name (char * fname)

+{

+  FILE * tfile;

+

+  /* Keep generating file names till we find one that's not in use */

+  for (;;) {

+    next_file_num++;		/* advance counter */

+    sprintf(fname, TEMP_FILE_NAME, TEMP_DIRECTORY, next_file_num);

+    if ((tfile = fopen(fname, READ_BINARY)) == NULL) {

+      /* fopen could have failed for a reason other than the file not

+       * being there; for example, file there but unreadable.

+       * If <errno.h> isn't available, then we cannot test the cause.

+       */

+#ifdef ENOENT

+      if (errno != ENOENT)

+	continue;

+#endif

+      break;

+    }

+    fclose(tfile);		/* oops, it's there; close tfile & try again */

+  }

+}

+

+#else /* ! NO_MKTEMP */

+

+/* Note that mktemp() requires the initial filename to end in six X's */

+#ifndef TEMP_FILE_NAME		/* can override from jconfig.h or Makefile */

+#define TEMP_FILE_NAME  "%sJPG%dXXXXXX"

+#endif

+

+LOCAL void

+select_file_name (char * fname)

+{

+  next_file_num++;		/* advance counter */

+  sprintf(fname, TEMP_FILE_NAME, TEMP_DIRECTORY, next_file_num);

+  mktemp(fname);		/* make sure file name is unique */

+  /* mktemp replaces the trailing XXXXXX with a unique string of characters */

+}

+

+#endif /* NO_MKTEMP */

+

+

+/*

+ * Memory allocation and freeing are controlled by the regular library

+ * routines malloc() and free().

+ */

+

+GLOBAL void *

+jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void *) malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)

+{

+  free(object);

+}

+

+

+/*

+ * "Large" objects are treated the same as "small" ones.

+ * NB: although we include FAR keywords in the routine declarations,

+ * this file won't actually work in 80x86 small/medium model; at least,

+ * you probably won't be able to process useful-size images in only 64KB.

+ */

+

+GLOBAL void FAR *

+jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void FAR *) malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)

+{

+  free(object);

+}

+

+

+/*

+ * This routine computes the total memory space available for allocation.

+ * It's impossible to do this in a portable way; our current solution is

+ * to make the user tell us (with a default value set at compile time).

+ * If you can actually get the available space, it's a good idea to subtract

+ * a slop factor of 5% or so.

+ */

+

+#ifndef DEFAULT_MAX_MEM		/* so can override from makefile */

+#define DEFAULT_MAX_MEM		1000000L /* default: one megabyte */

+#endif

+

+GLOBAL long

+jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,

+		    long max_bytes_needed, long already_allocated)

+{

+  return cinfo->mem->max_memory_to_use - already_allocated;

+}

+

+

+/*

+ * Backing store (temporary file) management.

+ * Backing store objects are only used when the value returned by

+ * jpeg_mem_available is less than the total space needed.  You can dispense

+ * with these routines if you have plenty of virtual memory; see jmemnobs.c.

+ */

+

+

+METHODDEF void

+read_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+		    void FAR * buffer_address,

+		    long file_offset, long byte_count)

+{

+  if (fseek(info->temp_file, file_offset, SEEK_SET))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  if (JFREAD(info->temp_file, buffer_address, byte_count)

+      != (size_t) byte_count)

+    ERREXIT(cinfo, JERR_TFILE_READ);

+}

+

+

+METHODDEF void

+write_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+		     void FAR * buffer_address,

+		     long file_offset, long byte_count)

+{

+  if (fseek(info->temp_file, file_offset, SEEK_SET))

+    ERREXIT(cinfo, JERR_TFILE_SEEK);

+  if (JFWRITE(info->temp_file, buffer_address, byte_count)

+      != (size_t) byte_count)

+    ERREXIT(cinfo, JERR_TFILE_WRITE);

+}

+

+

+METHODDEF void

+close_backing_store (j_common_ptr cinfo, backing_store_ptr info)

+{

+  fclose(info->temp_file);	/* close the file */

+  unlink(info->temp_name);	/* delete the file */

+/* If your system doesn't have unlink(), use remove() instead.

+ * remove() is the ANSI-standard name for this function, but if

+ * your system was ANSI you'd be using jmemansi.c, right?

+ */

+  TRACEMSS(cinfo, 1, JTRC_TFILE_CLOSE, info->temp_name);

+}

+

+

+/*

+ * Initial opening of a backing-store object.

+ */

+

+GLOBAL void

+jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+			 long total_bytes_needed)

+{

+  select_file_name(info->temp_name);

+  if ((info->temp_file = fopen(info->temp_name, RW_BINARY)) == NULL)

+    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);

+  info->read_backing_store = read_backing_store;

+  info->write_backing_store = write_backing_store;

+  info->close_backing_store = close_backing_store;

+  TRACEMSS(cinfo, 1, JTRC_TFILE_OPEN, info->temp_name);

+}

+

+

+/*

+ * These routines take care of any system-dependent initialization and

+ * cleanup required.

+ */

+

+GLOBAL long

+jpeg_mem_init (j_common_ptr cinfo)

+{

+  next_file_num = 0;		/* initialize temp file name generator */

+  return DEFAULT_MAX_MEM;	/* default for max_memory_to_use */

+}

+

+GLOBAL void

+jpeg_mem_term (j_common_ptr cinfo)

+{

+  /* no work */

+}

diff --git a/code/jpeg-6/jmemnobs.c b/code/jpeg-6/jmemnobs.c
new file mode 100755
index 0000000..50090c7
--- /dev/null
+++ b/code/jpeg-6/jmemnobs.c
@@ -0,0 +1,105 @@
+/*

+ * jmemnobs.c

+ *

+ * Copyright (C) 1992-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file provides a really simple implementation of the system-

+ * dependent portion of the JPEG memory manager.  This implementation

+ * assumes that no backing-store files are needed: all required space

+ * can be obtained from ri.Malloc().

+ * This is very portable in the sense that it'll compile on almost anything,

+ * but you'd better have lots of main memory (or virtual memory) if you want

+ * to process big images.

+ * Note that the max_memory_to_use option is ignored by this implementation.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+#include "jmemsys.h"		/* import the system-dependent declarations */

+

+#include "../renderer/tr_local.h"

+

+/*

+ * Memory allocation and ri.Freeing are controlled by the regular library

+ * routines ri.Malloc() and ri.Free().

+ */

+

+GLOBAL void *

+jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void *) ri.Malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)

+{

+  ri.Free(object);

+}

+

+

+/*

+ * "Large" objects are treated the same as "small" ones.

+ * NB: although we include FAR keywords in the routine declarations,

+ * this file won't actually work in 80x86 small/medium model; at least,

+ * you probably won't be able to process useful-size images in only 64KB.

+ */

+

+GLOBAL void FAR *

+jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)

+{

+  return (void FAR *) ri.Malloc(sizeofobject);

+}

+

+GLOBAL void

+jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)

+{

+  ri.Free(object);

+}

+

+

+/*

+ * This routine computes the total memory space available for allocation.

+ * Here we always say, "we got all you want bud!"

+ */

+

+GLOBAL long

+jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,

+		    long max_bytes_needed, long already_allocated)

+{

+  return max_bytes_needed;

+}

+

+

+/*

+ * Backing store (temporary file) management.

+ * Since jpeg_mem_available always promised the moon,

+ * this should never be called and we can just error out.

+ */

+

+GLOBAL void

+jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,

+			 long total_bytes_needed)

+{

+  ERREXIT(cinfo, JERR_NO_BACKING_STORE);

+}

+

+

+/*

+ * These routines take care of any system-dependent initialization and

+ * cleanup required.  Here, there isn't any.

+ */

+

+GLOBAL long

+jpeg_mem_init (j_common_ptr cinfo)

+{

+  return 0;			/* just set max_memory_to_use to 0 */

+}

+

+GLOBAL void

+jpeg_mem_term (j_common_ptr cinfo)

+{

+  /* no work */

+}

diff --git a/code/jpeg-6/jmemsys.h b/code/jpeg-6/jmemsys.h
new file mode 100755
index 0000000..0c7d7c1
--- /dev/null
+++ b/code/jpeg-6/jmemsys.h
@@ -0,0 +1,182 @@
+/*

+ * jmemsys.h

+ *

+ * Copyright (C) 1992-1994, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This include file defines the interface between the system-independent

+ * and system-dependent portions of the JPEG memory manager.  No other

+ * modules need include it.  (The system-independent portion is jmemmgr.c;

+ * there are several different versions of the system-dependent portion.)

+ *

+ * This file works as-is for the system-dependent memory managers supplied

+ * in the IJG distribution.  You may need to modify it if you write a

+ * custom memory manager.  If system-dependent changes are needed in

+ * this file, the best method is to #ifdef them based on a configuration

+ * symbol supplied in jconfig.h, as we have done with USE_MSDOS_MEMMGR.

+ */

+

+

+/* Short forms of external names for systems with brain-damaged linkers. */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_get_small		jGetSmall

+#define jpeg_free_small		jFreeSmall

+#define jpeg_get_large		jGetLarge

+#define jpeg_free_large		jFreeLarge

+#define jpeg_mem_available	jMemAvail

+#define jpeg_open_backing_store	jOpenBackStore

+#define jpeg_mem_init		jMemInit

+#define jpeg_mem_term		jMemTerm

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+

+/*

+ * These two functions are used to allocate and release small chunks of

+ * memory.  (Typically the total amount requested through jpeg_get_small is

+ * no more than 20K or so; this will be requested in chunks of a few K each.)

+ * Behavior should be the same as for the standard library functions malloc

+ * and free; in particular, jpeg_get_small must return NULL on failure.

+ * On most systems, these ARE malloc and free.  jpeg_free_small is passed the

+ * size of the object being freed, just in case it's needed.

+ * On an 80x86 machine using small-data memory model, these manage near heap.

+ */

+

+EXTERN void * jpeg_get_small JPP((j_common_ptr cinfo, size_t sizeofobject));

+EXTERN void jpeg_free_small JPP((j_common_ptr cinfo, void * object,

+				 size_t sizeofobject));

+

+/*

+ * These two functions are used to allocate and release large chunks of

+ * memory (up to the total free space designated by jpeg_mem_available).

+ * The interface is the same as above, except that on an 80x86 machine,

+ * far pointers are used.  On most other machines these are identical to

+ * the jpeg_get/free_small routines; but we keep them separate anyway,

+ * in case a different allocation strategy is desirable for large chunks.

+ */

+

+EXTERN void FAR * jpeg_get_large JPP((j_common_ptr cinfo,size_t sizeofobject));

+EXTERN void jpeg_free_large JPP((j_common_ptr cinfo, void FAR * object,

+				 size_t sizeofobject));

+

+/*

+ * The macro MAX_ALLOC_CHUNK designates the maximum number of bytes that may

+ * be requested in a single call to jpeg_get_large (and jpeg_get_small for that

+ * matter, but that case should never come into play).  This macro is needed

+ * to model the 64Kb-segment-size limit of far addressing on 80x86 machines.

+ * On those machines, we expect that jconfig.h will provide a proper value.

+ * On machines with 32-bit flat address spaces, any large constant may be used.

+ *

+ * NB: jmemmgr.c expects that MAX_ALLOC_CHUNK will be representable as type

+ * size_t and will be a multiple of sizeof(align_type).

+ */

+

+#ifndef MAX_ALLOC_CHUNK		/* may be overridden in jconfig.h */

+#define MAX_ALLOC_CHUNK  1000000000L

+#endif

+

+/*

+ * This routine computes the total space still available for allocation by

+ * jpeg_get_large.  If more space than this is needed, backing store will be

+ * used.  NOTE: any memory already allocated must not be counted.

+ *

+ * There is a minimum space requirement, corresponding to the minimum

+ * feasible buffer sizes; jmemmgr.c will request that much space even if

+ * jpeg_mem_available returns zero.  The maximum space needed, enough to hold

+ * all working storage in memory, is also passed in case it is useful.

+ * Finally, the total space already allocated is passed.  If no better

+ * method is available, cinfo->mem->max_memory_to_use - already_allocated

+ * is often a suitable calculation.

+ *

+ * It is OK for jpeg_mem_available to underestimate the space available

+ * (that'll just lead to more backing-store access than is really necessary).

+ * However, an overestimate will lead to failure.  Hence it's wise to subtract

+ * a slop factor from the true available space.  5% should be enough.

+ *

+ * On machines with lots of virtual memory, any large constant may be returned.

+ * Conversely, zero may be returned to always use the minimum amount of memory.

+ */

+

+EXTERN long jpeg_mem_available JPP((j_common_ptr cinfo,

+				    long min_bytes_needed,

+				    long max_bytes_needed,

+				    long already_allocated));

+

+

+/*

+ * This structure holds whatever state is needed to access a single

+ * backing-store object.  The read/write/close method pointers are called

+ * by jmemmgr.c to manipulate the backing-store object; all other fields

+ * are private to the system-dependent backing store routines.

+ */

+

+#define TEMP_NAME_LENGTH   64	/* max length of a temporary file's name */

+

+#ifdef USE_MSDOS_MEMMGR		/* DOS-specific junk */

+

+typedef unsigned short XMSH;	/* type of extended-memory handles */

+typedef unsigned short EMSH;	/* type of expanded-memory handles */

+

+typedef union {

+  short file_handle;		/* DOS file handle if it's a temp file */

+  XMSH xms_handle;		/* handle if it's a chunk of XMS */

+  EMSH ems_handle;		/* handle if it's a chunk of EMS */

+} handle_union;

+

+#endif /* USE_MSDOS_MEMMGR */

+

+typedef struct backing_store_struct * backing_store_ptr;

+

+typedef struct backing_store_struct {

+  /* Methods for reading/writing/closing this backing-store object */

+  JMETHOD(void, read_backing_store, (j_common_ptr cinfo,

+				     backing_store_ptr info,

+				     void FAR * buffer_address,

+				     long file_offset, long byte_count));

+  JMETHOD(void, write_backing_store, (j_common_ptr cinfo,

+				      backing_store_ptr info,

+				      void FAR * buffer_address,

+				      long file_offset, long byte_count));

+  JMETHOD(void, close_backing_store, (j_common_ptr cinfo,

+				      backing_store_ptr info));

+

+  /* Private fields for system-dependent backing-store management */

+#ifdef USE_MSDOS_MEMMGR

+  /* For the MS-DOS manager (jmemdos.c), we need: */

+  handle_union handle;		/* reference to backing-store storage object */

+  char temp_name[TEMP_NAME_LENGTH]; /* name if it's a file */

+#else

+  /* For a typical implementation with temp files, we need: */

+  FILE * temp_file;		/* stdio reference to temp file */

+  char temp_name[TEMP_NAME_LENGTH]; /* name of temp file */

+#endif

+} backing_store_info;

+

+/*

+ * Initial opening of a backing-store object.  This must fill in the

+ * read/write/close pointers in the object.  The read/write routines

+ * may take an error exit if the specified maximum file size is exceeded.

+ * (If jpeg_mem_available always returns a large value, this routine can

+ * just take an error exit.)

+ */

+

+EXTERN void jpeg_open_backing_store JPP((j_common_ptr cinfo,

+					 backing_store_ptr info,

+					 long total_bytes_needed));

+

+

+/*

+ * These routines take care of any system-dependent initialization and

+ * cleanup required.  jpeg_mem_init will be called before anything is

+ * allocated (and, therefore, nothing in cinfo is of use except the error

+ * manager pointer).  It should return a suitable default value for

+ * max_memory_to_use; this may subsequently be overridden by the surrounding

+ * application.  (Note that max_memory_to_use is only important if

+ * jpeg_mem_available chooses to consult it ... no one else will.)

+ * jpeg_mem_term may assume that all requested memory has been freed and that

+ * all opened backing-store objects have been closed.

+ */

+

+EXTERN long jpeg_mem_init JPP((j_common_ptr cinfo));

+EXTERN void jpeg_mem_term JPP((j_common_ptr cinfo));

diff --git a/code/jpeg-6/jmorecfg.h b/code/jpeg-6/jmorecfg.h
new file mode 100755
index 0000000..204dbbd
--- /dev/null
+++ b/code/jpeg-6/jmorecfg.h
@@ -0,0 +1,348 @@
+/*

+ * jmorecfg.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains additional configuration options that customize the

+ * JPEG software for special applications or support machine-dependent

+ * optimizations.  Most users will not need to touch this file.

+ */

+

+

+/*

+ * Define BITS_IN_JSAMPLE as either

+ *   8   for 8-bit sample values (the usual setting)

+ *   12  for 12-bit sample values

+ * Only 8 and 12 are legal data precisions for lossy JPEG according to the

+ * JPEG standard, and the IJG code does not support anything else!

+ * We do not support run-time selection of data precision, sorry.

+ */

+

+#define BITS_IN_JSAMPLE  8	/* use 8 or 12 */

+

+

+/*

+ * Maximum number of components (color channels) allowed in JPEG image.

+ * To meet the letter of the JPEG spec, set this to 255.  However, darn

+ * few applications need more than 4 channels (maybe 5 for CMYK + alpha

+ * mask).  We recommend 10 as a reasonable compromise; use 4 if you are

+ * really short on memory.  (Each allowed component costs a hundred or so

+ * bytes of storage, whether actually used in an image or not.)

+ */

+

+#define MAX_COMPONENTS  10	/* maximum number of image components */

+

+

+/*

+ * Basic data types.

+ * You may need to change these if you have a machine with unusual data

+ * type sizes; for example, "char" not 8 bits, "short" not 16 bits,

+ * or "long" not 32 bits.  We don't care whether "int" is 16 or 32 bits,

+ * but it had better be at least 16.

+ */

+

+/* Representation of a single sample (pixel element value).

+ * We frequently allocate large arrays of these, so it's important to keep

+ * them small.  But if you have memory to burn and access to char or short

+ * arrays is very slow on your hardware, you might want to change these.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+/* JSAMPLE should be the smallest type that will hold the values 0..255.

+ * You can use a signed char by having GETJSAMPLE mask it with 0xFF.

+ */

+

+#ifdef HAVE_UNSIGNED_CHAR

+

+typedef unsigned char JSAMPLE;

+#define GETJSAMPLE(value)  ((int) (value))

+

+#else /* not HAVE_UNSIGNED_CHAR */

+

+typedef char JSAMPLE;

+#ifdef CHAR_IS_UNSIGNED

+#define GETJSAMPLE(value)  ((int) (value))

+#else

+#define GETJSAMPLE(value)  ((int) (value) & 0xFF)

+#endif /* CHAR_IS_UNSIGNED */

+

+#endif /* HAVE_UNSIGNED_CHAR */

+

+#define MAXJSAMPLE	255

+#define CENTERJSAMPLE	128

+

+#endif /* BITS_IN_JSAMPLE == 8 */

+

+

+#if BITS_IN_JSAMPLE == 12

+/* JSAMPLE should be the smallest type that will hold the values 0..4095.

+ * On nearly all machines "short" will do nicely.

+ */

+

+typedef short JSAMPLE;

+#define GETJSAMPLE(value)  ((int) (value))

+

+#define MAXJSAMPLE	4095

+#define CENTERJSAMPLE	2048

+

+#endif /* BITS_IN_JSAMPLE == 12 */

+

+

+/* Representation of a DCT frequency coefficient.

+ * This should be a signed value of at least 16 bits; "short" is usually OK.

+ * Again, we allocate large arrays of these, but you can change to int

+ * if you have memory to burn and "short" is really slow.

+ */

+

+typedef short JCOEF;

+

+

+/* Compressed datastreams are represented as arrays of JOCTET.

+ * These must be EXACTLY 8 bits wide, at least once they are written to

+ * external storage.  Note that when using the stdio data source/destination

+ * managers, this is also the data type passed to fread/fwrite.

+ */

+

+#ifdef HAVE_UNSIGNED_CHAR

+

+typedef unsigned char JOCTET;

+#define GETJOCTET(value)  (value)

+

+#else /* not HAVE_UNSIGNED_CHAR */

+

+typedef char JOCTET;

+#ifdef CHAR_IS_UNSIGNED

+#define GETJOCTET(value)  (value)

+#else

+#define GETJOCTET(value)  ((value) & 0xFF)

+#endif /* CHAR_IS_UNSIGNED */

+

+#endif /* HAVE_UNSIGNED_CHAR */

+

+

+/* These typedefs are used for various table entries and so forth.

+ * They must be at least as wide as specified; but making them too big

+ * won't cost a huge amount of memory, so we don't provide special

+ * extraction code like we did for JSAMPLE.  (In other words, these

+ * typedefs live at a different point on the speed/space tradeoff curve.)

+ */

+

+/* UINT8 must hold at least the values 0..255. */

+

+#ifdef HAVE_UNSIGNED_CHAR

+typedef unsigned char UINT8;

+#else /* not HAVE_UNSIGNED_CHAR */

+#ifdef CHAR_IS_UNSIGNED

+typedef char UINT8;

+#else /* not CHAR_IS_UNSIGNED */

+typedef short UINT8;

+#endif /* CHAR_IS_UNSIGNED */

+#endif /* HAVE_UNSIGNED_CHAR */

+

+/* UINT16 must hold at least the values 0..65535. */

+

+#ifdef HAVE_UNSIGNED_SHORT

+typedef unsigned short UINT16;

+#else /* not HAVE_UNSIGNED_SHORT */

+typedef unsigned int UINT16;

+#endif /* HAVE_UNSIGNED_SHORT */

+

+typedef long INT32;

+

+/* INT16 must hold at least the values -32768..32767. */

+

+#ifndef XMD_H			/* X11/xmd.h correctly defines INT16 */

+typedef short INT16;

+#endif

+

+/* INT32 must hold at least signed 32-bit values. */

+

+//#ifndef XMD_H			/* X11/xmd.h correctly defines INT32 */

+//typedef long INT32;

+//#endif

+

+/* Datatype used for image dimensions.  The JPEG standard only supports

+ * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore

+ * "unsigned int" is sufficient on all machines.  However, if you need to

+ * handle larger images and you don't mind deviating from the spec, you

+ * can change this datatype.

+ */

+

+typedef unsigned int JDIMENSION;

+

+#define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */

+

+

+/* These defines are used in all function definitions and extern declarations.

+ * You could modify them if you need to change function linkage conventions.

+ * Another application is to make all functions global for use with debuggers

+ * or code profilers that require it.

+ */

+

+#define METHODDEF static	/* a function called through method pointers */

+#define LOCAL	  static	/* a function used only in its module */

+#define GLOBAL			/* a function referenced thru EXTERNs */

+#define EXTERN	  extern	/* a reference to a GLOBAL function */

+

+

+/* Here is the pseudo-keyword for declaring pointers that must be "far"

+ * on 80x86 machines.  Most of the specialized coding for 80x86 is handled

+ * by just saying "FAR *" where such a pointer is needed.  In a few places

+ * explicit coding is needed; see uses of the NEED_FAR_POINTERS symbol.

+ */

+

+#ifdef NEED_FAR_POINTERS

+#undef FAR

+#define FAR  far

+#else

+#undef FAR

+#define FAR

+#endif

+

+

+/*

+ * On a few systems, type boolean and/or its values FALSE, TRUE may appear

+ * in standard header files.  Or you may have conflicts with application-

+ * specific header files that you want to include together with these files.

+ * Defining HAVE_BOOLEAN before including jpeglib.h should make it work.

+ */

+

+//#ifndef HAVE_BOOLEAN

+//typedef int boolean;

+//#endif

+#ifndef FALSE			/* in case these macros already exist */

+#define FALSE	0		/* values of boolean */

+#endif

+#ifndef TRUE

+#define TRUE	1

+#endif

+

+

+/*

+ * The remaining options affect code selection within the JPEG library,

+ * but they don't need to be visible to most applications using the library.

+ * To minimize application namespace pollution, the symbols won't be

+ * defined unless JPEG_INTERNALS or JPEG_INTERNAL_OPTIONS has been defined.

+ */

+

+#ifdef JPEG_INTERNALS

+#define JPEG_INTERNAL_OPTIONS

+#endif

+

+#ifdef JPEG_INTERNAL_OPTIONS

+

+

+/*

+ * These defines indicate whether to include various optional functions.

+ * Undefining some of these symbols will produce a smaller but less capable

+ * library.  Note that you can leave certain source files out of the

+ * compilation/linking process if you've #undef'd the corresponding symbols.

+ * (You may HAVE to do that if your compiler doesn't like null source files.)

+ */

+

+/* Arithmetic coding is unsupported for legal reasons.  Complaints to IBM. */

+

+/* Capability options common to encoder and decoder: */

+

+#undef DCT_ISLOW_SUPPORTED	/* slow but accurate integer algorithm */

+#undef DCT_IFAST_SUPPORTED	/* faster, less accurate integer method */

+#define DCT_FLOAT_SUPPORTED	/* floating-point: accurate, fast on fast HW */

+

+/* Encoder capability options: */

+

+#undef  C_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */

+#define C_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */

+#define C_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/

+#define ENTROPY_OPT_SUPPORTED	    /* Optimization of entropy coding parms? */

+/* Note: if you selected 12-bit data precision, it is dangerous to turn off

+ * ENTROPY_OPT_SUPPORTED.  The standard Huffman tables are only good for 8-bit

+ * precision, so jchuff.c normally uses entropy optimization to compute

+ * usable tables for higher precision.  If you don't want to do optimization,

+ * you'll have to supply different default Huffman tables.

+ * The exact same statements apply for progressive JPEG: the default tables

+ * don't work for progressive mode.  (This may get fixed, however.)

+ */

+#define INPUT_SMOOTHING_SUPPORTED   /* Input image smoothing option? */

+

+/* Decoder capability options: */

+

+#undef  D_ARITH_CODING_SUPPORTED    /* Arithmetic coding back end? */

+#undef D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */

+#undef D_PROGRESSIVE_SUPPORTED	    /* Progressive JPEG? (Requires MULTISCAN)*/

+#undef BLOCK_SMOOTHING_SUPPORTED   /* Block smoothing? (Progressive only) */

+#undef IDCT_SCALING_SUPPORTED	    /* Output rescaling via IDCT? */

+#undef  UPSAMPLE_SCALING_SUPPORTED  /* Output rescaling at upsample stage? */

+#undef UPSAMPLE_MERGING_SUPPORTED  /* Fast path for sloppy upsampling? */

+#undef QUANT_1PASS_SUPPORTED	    /* 1-pass color quantization? */

+#undef QUANT_2PASS_SUPPORTED	    /* 2-pass color quantization? */

+

+/* more capability options later, no doubt */

+

+

+/*

+ * Ordering of RGB data in scanlines passed to or from the application.

+ * If your application wants to deal with data in the order B,G,R, just

+ * change these macros.  You can also deal with formats such as R,G,B,X

+ * (one extra byte per pixel) by changing RGB_PIXELSIZE.  Note that changing

+ * the offsets will also change the order in which colormap data is organized.

+ * RESTRICTIONS:

+ * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats.

+ * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not

+ *    useful if you are using JPEG color spaces other than YCbCr or grayscale.

+ * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE

+ *    is not 3 (they don't understand about dummy color components!).  So you

+ *    can't use color quantization if you change that value.

+ */

+

+#define RGB_RED		0	/* Offset of Red in an RGB scanline element */

+#define RGB_GREEN	1	/* Offset of Green */

+#define RGB_BLUE	2	/* Offset of Blue */

+#define RGB_PIXELSIZE	4	/* JSAMPLEs per RGB scanline element */

+

+

+/* Definitions for speed-related optimizations. */

+

+

+/* If your compiler supports inline functions, define INLINE

+ * as the inline keyword; otherwise define it as empty.

+ */

+

+#ifndef INLINE

+#ifdef __GNUC__			/* for instance, GNU C knows about inline */

+#define INLINE __inline__

+#endif

+#ifndef INLINE

+#define INLINE			/* default is to define it as empty */

+#endif

+#endif

+

+

+/* On some machines (notably 68000 series) "int" is 32 bits, but multiplying

+ * two 16-bit shorts is faster than multiplying two ints.  Define MULTIPLIER

+ * as short on such a machine.  MULTIPLIER must be at least 16 bits wide.

+ */

+

+#ifndef MULTIPLIER

+#define MULTIPLIER  int		/* type for fastest integer multiply */

+#endif

+

+

+/* FAST_FLOAT should be either float or double, whichever is done faster

+ * by your compiler.  (Note that this type is only used in the floating point

+ * DCT routines, so it only matters if you've defined DCT_FLOAT_SUPPORTED.)

+ * Typically, float is faster in ANSI C compilers, while double is faster in

+ * pre-ANSI compilers (because they insist on converting to double anyway).

+ * The code below therefore chooses float if we have ANSI-style prototypes.

+ */

+

+#ifndef FAST_FLOAT

+#ifdef HAVE_PROTOTYPES

+#define FAST_FLOAT  float

+#else

+#define FAST_FLOAT  double

+#endif

+#endif

+

+#endif /* JPEG_INTERNAL_OPTIONS */

diff --git a/code/jpeg-6/jpegint.h b/code/jpeg-6/jpegint.h
new file mode 100755
index 0000000..b3b6a6d
--- /dev/null
+++ b/code/jpeg-6/jpegint.h
@@ -0,0 +1,388 @@
+/*

+ * jpegint.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file provides common declarations for the various JPEG modules.

+ * These declarations are considered internal to the JPEG library; most

+ * applications using the library shouldn't need to include this file.

+ */

+

+

+/* Declarations for both compression & decompression */

+

+typedef enum {			/* Operating modes for buffer controllers */

+	JBUF_PASS_THRU,		/* Plain stripwise operation */

+	/* Remaining modes require a full-image buffer to have been created */

+	JBUF_SAVE_SOURCE,	/* Run source subobject only, save output */

+	JBUF_CRANK_DEST,	/* Run dest subobject only, using saved data */

+	JBUF_SAVE_AND_PASS	/* Run both subobjects, save output */

+} J_BUF_MODE;

+

+/* Values of global_state field (jdapi.c has some dependencies on ordering!) */

+#define CSTATE_START	100	/* after create_compress */

+#define CSTATE_SCANNING	101	/* start_compress done, write_scanlines OK */

+#define CSTATE_RAW_OK	102	/* start_compress done, write_raw_data OK */

+#define CSTATE_WRCOEFS	103	/* jpeg_write_coefficients done */

+#define DSTATE_START	200	/* after create_decompress */

+#define DSTATE_INHEADER	201	/* reading header markers, no SOS yet */

+#define DSTATE_READY	202	/* found SOS, ready for start_decompress */

+#define DSTATE_PRELOAD	203	/* reading multiscan file in start_decompress*/

+#define DSTATE_PRESCAN	204	/* performing dummy pass for 2-pass quant */

+#define DSTATE_SCANNING	205	/* start_decompress done, read_scanlines OK */

+#define DSTATE_RAW_OK	206	/* start_decompress done, read_raw_data OK */

+#define DSTATE_BUFIMAGE	207	/* expecting jpeg_start_output */

+#define DSTATE_BUFPOST	208	/* looking for SOS/EOI in jpeg_finish_output */

+#define DSTATE_RDCOEFS	209	/* reading file in jpeg_read_coefficients */

+#define DSTATE_STOPPING	210	/* looking for EOI in jpeg_finish_decompress */

+

+

+/* Declarations for compression modules */

+

+/* Master control module */

+struct jpeg_comp_master {

+  JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo));

+  JMETHOD(void, pass_startup, (j_compress_ptr cinfo));

+  JMETHOD(void, finish_pass, (j_compress_ptr cinfo));

+

+  /* State variables made visible to other modules */

+  boolean call_pass_startup;	/* True if pass_startup must be called */

+  boolean is_last_pass;		/* True during last pass */

+};

+

+/* Main buffer control (downsampled-data buffer) */

+struct jpeg_c_main_controller {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));

+  JMETHOD(void, process_data, (j_compress_ptr cinfo,

+			       JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,

+			       JDIMENSION in_rows_avail));

+};

+

+/* Compression preprocessing (downsampling input buffer control) */

+struct jpeg_c_prep_controller {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));

+  JMETHOD(void, pre_process_data, (j_compress_ptr cinfo,

+				   JSAMPARRAY input_buf,

+				   JDIMENSION *in_row_ctr,

+				   JDIMENSION in_rows_avail,

+				   JSAMPIMAGE output_buf,

+				   JDIMENSION *out_row_group_ctr,

+				   JDIMENSION out_row_groups_avail));

+};

+

+/* Coefficient buffer control */

+struct jpeg_c_coef_controller {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));

+  JMETHOD(boolean, compress_data, (j_compress_ptr cinfo,

+				   JSAMPIMAGE input_buf));

+};

+

+/* Colorspace conversion */

+struct jpeg_color_converter {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo));

+  JMETHOD(void, color_convert, (j_compress_ptr cinfo,

+				JSAMPARRAY input_buf, JSAMPIMAGE output_buf,

+				JDIMENSION output_row, int num_rows));

+};

+

+/* Downsampling */

+struct jpeg_downsampler {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo));

+  JMETHOD(void, downsample, (j_compress_ptr cinfo,

+			     JSAMPIMAGE input_buf, JDIMENSION in_row_index,

+			     JSAMPIMAGE output_buf,

+			     JDIMENSION out_row_group_index));

+

+  boolean need_context_rows;	/* TRUE if need rows above & below */

+};

+

+/* Forward DCT (also controls coefficient quantization) */

+struct jpeg_forward_dct {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo));

+  /* perhaps this should be an array??? */

+  JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,

+			      jpeg_component_info * compptr,

+			      JSAMPARRAY sample_data, JBLOCKROW coef_blocks,

+			      JDIMENSION start_row, JDIMENSION start_col,

+			      JDIMENSION num_blocks));

+};

+

+/* Entropy encoding */

+struct jpeg_entropy_encoder {

+  JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));

+  JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));

+  JMETHOD(void, finish_pass, (j_compress_ptr cinfo));

+};

+

+/* Marker writing */

+struct jpeg_marker_writer {

+  /* write_any_marker is exported for use by applications */

+  /* Probably only COM and APPn markers should be written */

+  JMETHOD(void, write_any_marker, (j_compress_ptr cinfo, int marker,

+				   const JOCTET *dataptr, unsigned int datalen));

+  JMETHOD(void, write_file_header, (j_compress_ptr cinfo));

+  JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));

+  JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));

+  JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));

+  JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));

+};

+

+

+/* Declarations for decompression modules */

+

+/* Master control module */

+struct jpeg_decomp_master {

+  JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));

+  JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));

+

+  /* State variables made visible to other modules */

+  boolean is_dummy_pass;	/* True during 1st pass for 2-pass quant */

+};

+

+/* Input control module */

+struct jpeg_input_controller {

+  JMETHOD(int, consume_input, (j_decompress_ptr cinfo));

+  JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));

+  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));

+  JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));

+

+  /* State variables made visible to other modules */

+  boolean has_multiple_scans;	/* True if file has multiple scans */

+  boolean eoi_reached;		/* True when EOI has been consumed */

+};

+

+/* Main buffer control (downsampled-data buffer) */

+struct jpeg_d_main_controller {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));

+  JMETHOD(void, process_data, (j_decompress_ptr cinfo,

+			       JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,

+			       JDIMENSION out_rows_avail));

+};

+

+/* Coefficient buffer control */

+struct jpeg_d_coef_controller {

+  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));

+  JMETHOD(int, consume_data, (j_decompress_ptr cinfo));

+  JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));

+  JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,

+				 JSAMPIMAGE output_buf));

+  /* Pointer to array of coefficient virtual arrays, or NULL if none */

+  jvirt_barray_ptr *coef_arrays;

+};

+

+/* Decompression postprocessing (color quantization buffer control) */

+struct jpeg_d_post_controller {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));

+  JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,

+				    JSAMPIMAGE input_buf,

+				    JDIMENSION *in_row_group_ctr,

+				    JDIMENSION in_row_groups_avail,

+				    JSAMPARRAY output_buf,

+				    JDIMENSION *out_row_ctr,

+				    JDIMENSION out_rows_avail));

+};

+

+/* Marker reading & parsing */

+struct jpeg_marker_reader {

+  JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));

+  /* Read markers until SOS or EOI.

+   * Returns same codes as are defined for jpeg_consume_input:

+   * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.

+   */

+  JMETHOD(int, read_markers, (j_decompress_ptr cinfo));

+  /* Read a restart marker --- exported for use by entropy decoder only */

+  jpeg_marker_parser_method read_restart_marker;

+  /* Application-overridable marker processing methods */

+  jpeg_marker_parser_method process_COM;

+  jpeg_marker_parser_method process_APPn[16];

+

+  /* State of marker reader --- nominally internal, but applications

+   * supplying COM or APPn handlers might like to know the state.

+   */

+  boolean saw_SOI;		/* found SOI? */

+  boolean saw_SOF;		/* found SOF? */

+  int next_restart_num;		/* next restart number expected (0-7) */

+  unsigned int discarded_bytes;	/* # of bytes skipped looking for a marker */

+};

+

+/* Entropy decoding */

+struct jpeg_entropy_decoder {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));

+  JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,

+				JBLOCKROW *MCU_data));

+};

+

+/* Inverse DCT (also performs dequantization) */

+typedef JMETHOD(void, inverse_DCT_method_ptr,

+		(j_decompress_ptr cinfo, jpeg_component_info * compptr,

+		 JCOEFPTR coef_block,

+		 JSAMPARRAY output_buf, JDIMENSION output_col));

+

+struct jpeg_inverse_dct {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));

+  /* It is useful to allow each component to have a separate IDCT method. */

+  inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];

+};

+

+/* Upsampling (note that upsampler must also call color converter) */

+struct jpeg_upsampler {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));

+  JMETHOD(void, upsample, (j_decompress_ptr cinfo,

+			   JSAMPIMAGE input_buf,

+			   JDIMENSION *in_row_group_ctr,

+			   JDIMENSION in_row_groups_avail,

+			   JSAMPARRAY output_buf,

+			   JDIMENSION *out_row_ctr,

+			   JDIMENSION out_rows_avail));

+

+  boolean need_context_rows;	/* TRUE if need rows above & below */

+};

+

+/* Colorspace conversion */

+struct jpeg_color_deconverter {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));

+  JMETHOD(void, color_convert, (j_decompress_ptr cinfo,

+				JSAMPIMAGE input_buf, JDIMENSION input_row,

+				JSAMPARRAY output_buf, int num_rows));

+};

+

+/* Color quantization or color precision reduction */

+struct jpeg_color_quantizer {

+  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));

+  JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,

+				 JSAMPARRAY input_buf, JSAMPARRAY output_buf,

+				 int num_rows));

+  JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));

+  JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));

+};

+

+

+/* Miscellaneous useful macros */

+

+#undef MAX

+#define MAX(a,b)	((a) > (b) ? (a) : (b))

+#undef MIN

+#define MIN(a,b)	((a) < (b) ? (a) : (b))

+

+

+/* We assume that right shift corresponds to signed division by 2 with

+ * rounding towards minus infinity.  This is correct for typical "arithmetic

+ * shift" instructions that shift in copies of the sign bit.  But some

+ * C compilers implement >> with an unsigned shift.  For these machines you

+ * must define RIGHT_SHIFT_IS_UNSIGNED.

+ * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.

+ * It is only applied with constant shift counts.  SHIFT_TEMPS must be

+ * included in the variables of any routine using RIGHT_SHIFT.

+ */

+

+#ifdef RIGHT_SHIFT_IS_UNSIGNED

+#define SHIFT_TEMPS	INT32 shift_temp;

+#define RIGHT_SHIFT(x,shft)  \

+	((shift_temp = (x)) < 0 ? \

+	 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \

+	 (shift_temp >> (shft)))

+#else

+#define SHIFT_TEMPS

+#define RIGHT_SHIFT(x,shft)	((x) >> (shft))

+#endif

+

+

+/* Short forms of external names for systems with brain-damaged linkers. */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jinit_compress_master	jICompress

+#define jinit_c_master_control	jICMaster

+#define jinit_c_main_controller	jICMainC

+#define jinit_c_prep_controller	jICPrepC

+#define jinit_c_coef_controller	jICCoefC

+#define jinit_color_converter	jICColor

+#define jinit_downsampler	jIDownsampler

+#define jinit_forward_dct	jIFDCT

+#define jinit_huff_encoder	jIHEncoder

+#define jinit_phuff_encoder	jIPHEncoder

+#define jinit_marker_writer	jIMWriter

+#define jinit_master_decompress	jIDMaster

+#define jinit_d_main_controller	jIDMainC

+#define jinit_d_coef_controller	jIDCoefC

+#define jinit_d_post_controller	jIDPostC

+#define jinit_input_controller	jIInCtlr

+#define jinit_marker_reader	jIMReader

+#define jinit_huff_decoder	jIHDecoder

+#define jinit_phuff_decoder	jIPHDecoder

+#define jinit_inverse_dct	jIIDCT

+#define jinit_upsampler		jIUpsampler

+#define jinit_color_deconverter	jIDColor

+#define jinit_1pass_quantizer	jI1Quant

+#define jinit_2pass_quantizer	jI2Quant

+#define jinit_merged_upsampler	jIMUpsampler

+#define jinit_memory_mgr	jIMemMgr

+#define jdiv_round_up		jDivRound

+#define jround_up		jRound

+#define jcopy_sample_rows	jCopySamples

+#define jcopy_block_row		jCopyBlocks

+#define jzero_far		jZeroFar

+#define jpeg_zigzag_order	jZIGTable

+#define jpeg_natural_order	jZAGTable

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+

+/* Compression module initialization routines */

+EXTERN void jinit_compress_master JPP((j_compress_ptr cinfo));

+EXTERN void jinit_c_master_control JPP((j_compress_ptr cinfo,

+					boolean transcode_only));

+EXTERN void jinit_c_main_controller JPP((j_compress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_c_prep_controller JPP((j_compress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_c_coef_controller JPP((j_compress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_color_converter JPP((j_compress_ptr cinfo));

+EXTERN void jinit_downsampler JPP((j_compress_ptr cinfo));

+EXTERN void jinit_forward_dct JPP((j_compress_ptr cinfo));

+EXTERN void jinit_huff_encoder JPP((j_compress_ptr cinfo));

+EXTERN void jinit_phuff_encoder JPP((j_compress_ptr cinfo));

+EXTERN void jinit_marker_writer JPP((j_compress_ptr cinfo));

+/* Decompression module initialization routines */

+EXTERN void jinit_master_decompress JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_d_main_controller JPP((j_decompress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_d_coef_controller JPP((j_decompress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_d_post_controller JPP((j_decompress_ptr cinfo,

+					 boolean need_full_buffer));

+EXTERN void jinit_input_controller JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_marker_reader JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_huff_decoder JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_phuff_decoder JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_inverse_dct JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_upsampler JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_color_deconverter JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));

+EXTERN void jinit_merged_upsampler JPP((j_decompress_ptr cinfo));

+/* Memory manager initialization */

+EXTERN void jinit_memory_mgr JPP((j_common_ptr cinfo));

+

+/* Utility routines in jutils.c */

+EXTERN long jdiv_round_up JPP((long a, long b));

+EXTERN long jround_up JPP((long a, long b));

+EXTERN void jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,

+				   JSAMPARRAY output_array, int dest_row,

+				   int num_rows, JDIMENSION num_cols));

+EXTERN void jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,

+				 JDIMENSION num_blocks));

+EXTERN void jzero_far JPP((void FAR * target, size_t bytestozero));

+/* Constant tables in jutils.c */

+extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */

+extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */

+

+/* Suppress undefined-structure complaints if necessary. */

+

+#ifdef INCOMPLETE_TYPES_BROKEN

+#ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */

+struct jvirt_sarray_control { long dummy; };

+struct jvirt_barray_control { long dummy; };

+#endif

+#endif /* INCOMPLETE_TYPES_BROKEN */

diff --git a/code/jpeg-6/jpeglib.h b/code/jpeg-6/jpeglib.h
new file mode 100755
index 0000000..3c57308
--- /dev/null
+++ b/code/jpeg-6/jpeglib.h
@@ -0,0 +1,1051 @@
+/*

+ * jpeglib.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file defines the application interface for the JPEG library.

+ * Most applications using the library need only include this file,

+ * and perhaps jerror.h if they want to know the exact error codes.

+ */

+

+#ifndef JPEGLIB_H

+#define JPEGLIB_H

+

+typedef unsigned char boolean;

+/*

+ * First we include the configuration files that record how this

+ * installation of the JPEG library is set up.  jconfig.h can be

+ * generated automatically for many systems.  jmorecfg.h contains

+ * manual configuration options that most people need not worry about.

+ */

+

+#ifndef JCONFIG_INCLUDED	/* in case jinclude.h already did */

+#include "../jpeg-6/jconfig.h"		/* widely used configuration options */

+#endif

+#include "../jpeg-6/jmorecfg.h"		/* seldom changed options */

+

+

+/* Version ID for the JPEG library.

+ * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".

+ */

+

+#define JPEG_LIB_VERSION  60	/* Version 6 */

+

+

+/* Various constants determining the sizes of things.

+ * All of these are specified by the JPEG standard, so don't change them

+ * if you want to be compatible.

+ */

+

+#define DCTSIZE		    8	/* The basic DCT block is 8x8 samples */

+#define DCTSIZE2	    64	/* DCTSIZE squared; # of elements in a block */

+#define NUM_QUANT_TBLS      4	/* Quantization tables are numbered 0..3 */

+#define NUM_HUFF_TBLS       4	/* Huffman tables are numbered 0..3 */

+#define NUM_ARITH_TBLS      16	/* Arith-coding tables are numbered 0..15 */

+#define MAX_COMPS_IN_SCAN   4	/* JPEG limit on # of components in one scan */

+#define MAX_SAMP_FACTOR     4	/* JPEG limit on sampling factors */

+/* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;

+ * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.

+ * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU

+ * to handle it.  We even let you do this from the jconfig.h file.  However,

+ * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe

+ * sometimes emits noncompliant files doesn't mean you should too.

+ */

+#define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */

+#ifndef D_MAX_BLOCKS_IN_MCU

+#define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */

+#endif

+

+

+/* This macro is used to declare a "method", that is, a function pointer.

+ * We want to supply prototype parameters if the compiler can cope.

+ * Note that the arglist parameter must be parenthesized!

+ */

+

+#ifdef HAVE_PROTOTYPES

+#define JMETHOD(type,methodname,arglist)  type (*methodname) arglist

+#else

+#define JMETHOD(type,methodname,arglist)  type (*methodname) ()

+#endif

+

+

+/* Data structures for images (arrays of samples and of DCT coefficients).

+ * On 80x86 machines, the image arrays are too big for near pointers,

+ * but the pointer arrays can fit in near memory.

+ */

+

+typedef JSAMPLE FAR *JSAMPROW;	/* ptr to one image row of pixel samples. */

+typedef JSAMPROW *JSAMPARRAY;	/* ptr to some rows (a 2-D sample array) */

+typedef JSAMPARRAY *JSAMPIMAGE;	/* a 3-D sample array: top index is color */

+

+typedef JCOEF JBLOCK[DCTSIZE2];	/* one block of coefficients */

+typedef JBLOCK FAR *JBLOCKROW;	/* pointer to one row of coefficient blocks */

+typedef JBLOCKROW *JBLOCKARRAY;		/* a 2-D array of coefficient blocks */

+typedef JBLOCKARRAY *JBLOCKIMAGE;	/* a 3-D array of coefficient blocks */

+

+typedef JCOEF FAR *JCOEFPTR;	/* useful in a couple of places */

+

+

+/* Types for JPEG compression parameters and working tables. */

+

+

+/* DCT coefficient quantization tables. */

+

+typedef struct {

+  /* This field directly represents the contents of a JPEG DQT marker.

+   * Note: the values are always given in zigzag order.

+   */

+  UINT16 quantval[DCTSIZE2];	/* quantization step for each coefficient */

+  /* This field is used only during compression.  It's initialized FALSE when

+   * the table is created, and set TRUE when it's been output to the file.

+   * You could suppress output of a table by setting this to TRUE.

+   * (See jpeg_suppress_tables for an example.)

+   */

+  boolean sent_table;		/* TRUE when table has been output */

+} JQUANT_TBL;

+

+

+/* Huffman coding tables. */

+

+typedef struct {

+  /* These two fields directly represent the contents of a JPEG DHT marker */

+  UINT8 bits[17];		/* bits[k] = # of symbols with codes of */

+				/* length k bits; bits[0] is unused */

+  UINT8 huffval[256];		/* The symbols, in order of incr code length */

+  /* This field is used only during compression.  It's initialized FALSE when

+   * the table is created, and set TRUE when it's been output to the file.

+   * You could suppress output of a table by setting this to TRUE.

+   * (See jpeg_suppress_tables for an example.)

+   */

+  boolean sent_table;		/* TRUE when table has been output */

+} JHUFF_TBL;

+

+

+/* Basic info about one component (color channel). */

+

+typedef struct {

+  /* These values are fixed over the whole image. */

+  /* For compression, they must be supplied by parameter setup; */

+  /* for decompression, they are read from the SOF marker. */

+  int component_id;		/* identifier for this component (0..255) */

+  int component_index;		/* its index in SOF or cinfo->comp_info[] */

+  int h_samp_factor;		/* horizontal sampling factor (1..4) */

+  int v_samp_factor;		/* vertical sampling factor (1..4) */

+  int quant_tbl_no;		/* quantization table selector (0..3) */

+  /* These values may vary between scans. */

+  /* For compression, they must be supplied by parameter setup; */

+  /* for decompression, they are read from the SOS marker. */

+  /* The decompressor output side may not use these variables. */

+  int dc_tbl_no;		/* DC entropy table selector (0..3) */

+  int ac_tbl_no;		/* AC entropy table selector (0..3) */

+  

+  /* Remaining fields should be treated as private by applications. */

+  

+  /* These values are computed during compression or decompression startup: */

+  /* Component's size in DCT blocks.

+   * Any dummy blocks added to complete an MCU are not counted; therefore

+   * these values do not depend on whether a scan is interleaved or not.

+   */

+  JDIMENSION width_in_blocks;

+  JDIMENSION height_in_blocks;

+  /* Size of a DCT block in samples.  Always DCTSIZE for compression.

+   * For decompression this is the size of the output from one DCT block,

+   * reflecting any scaling we choose to apply during the IDCT step.

+   * Values of 1,2,4,8 are likely to be supported.  Note that different

+   * components may receive different IDCT scalings.

+   */

+  int DCT_scaled_size;

+  /* The downsampled dimensions are the component's actual, unpadded number

+   * of samples at the main buffer (preprocessing/compression interface), thus

+   * downsampled_width = ceil(image_width * Hi/Hmax)

+   * and similarly for height.  For decompression, IDCT scaling is included, so

+   * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)

+   */

+  JDIMENSION downsampled_width;	 /* actual width in samples */

+  JDIMENSION downsampled_height; /* actual height in samples */

+  /* This flag is used only for decompression.  In cases where some of the

+   * components will be ignored (eg grayscale output from YCbCr image),

+   * we can skip most computations for the unused components.

+   */

+  boolean component_needed;	/* do we need the value of this component? */

+

+  /* These values are computed before starting a scan of the component. */

+  /* The decompressor output side may not use these variables. */

+  int MCU_width;		/* number of blocks per MCU, horizontally */

+  int MCU_height;		/* number of blocks per MCU, vertically */

+  int MCU_blocks;		/* MCU_width * MCU_height */

+  int MCU_sample_width;		/* MCU width in samples, MCU_width*DCT_scaled_size */

+  int last_col_width;		/* # of non-dummy blocks across in last MCU */

+  int last_row_height;		/* # of non-dummy blocks down in last MCU */

+

+  /* Saved quantization table for component; NULL if none yet saved.

+   * See jdinput.c comments about the need for this information.

+   * This field is not currently used by the compressor.

+   */

+  JQUANT_TBL * quant_table;

+

+  /* Private per-component storage for DCT or IDCT subsystem. */

+  void * dct_table;

+} jpeg_component_info;

+

+

+/* The script for encoding a multiple-scan file is an array of these: */

+

+typedef struct {

+  int comps_in_scan;		/* number of components encoded in this scan */

+  int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */

+  int Ss, Se;			/* progressive JPEG spectral selection parms */

+  int Ah, Al;			/* progressive JPEG successive approx. parms */

+} jpeg_scan_info;

+

+

+/* Known color spaces. */

+

+typedef enum {

+	JCS_UNKNOWN,		/* error/unspecified */

+	JCS_GRAYSCALE,		/* monochrome */

+	JCS_RGB,		/* red/green/blue */

+	JCS_YCbCr,		/* Y/Cb/Cr (also known as YUV) */

+	JCS_CMYK,		/* C/M/Y/K */

+	JCS_YCCK		/* Y/Cb/Cr/K */

+} J_COLOR_SPACE;

+

+/* DCT/IDCT algorithm options. */

+

+typedef enum {

+	JDCT_ISLOW,		/* slow but accurate integer algorithm */

+	JDCT_IFAST,		/* faster, less accurate integer method */

+	JDCT_FLOAT		/* floating-point: accurate, fast on fast HW */

+} J_DCT_METHOD;

+

+#ifndef JDCT_DEFAULT		/* may be overridden in jconfig.h */

+#define JDCT_DEFAULT  JDCT_ISLOW

+#endif

+#ifndef JDCT_FASTEST		/* may be overridden in jconfig.h */

+#define JDCT_FASTEST  JDCT_IFAST

+#endif

+

+/* Dithering options for decompression. */

+

+typedef enum {

+	JDITHER_NONE,		/* no dithering */

+	JDITHER_ORDERED,	/* simple ordered dither */

+	JDITHER_FS		/* Floyd-Steinberg error diffusion dither */

+} J_DITHER_MODE;

+

+

+/* Common fields between JPEG compression and decompression master structs. */

+

+#define jpeg_common_fields \

+  struct jpeg_error_mgr * err;	/* Error handler module */\

+  struct jpeg_memory_mgr * mem;	/* Memory manager module */\

+  struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\

+  boolean is_decompressor;	/* so common code can tell which is which */\

+  int global_state		/* for checking call sequence validity */

+

+/* Routines that are to be used by both halves of the library are declared

+ * to receive a pointer to this structure.  There are no actual instances of

+ * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.

+ */

+struct jpeg_common_struct {

+  jpeg_common_fields;		/* Fields common to both master struct types */

+  /* Additional fields follow in an actual jpeg_compress_struct or

+   * jpeg_decompress_struct.  All three structs must agree on these

+   * initial fields!  (This would be a lot cleaner in C++.)

+   */

+};

+

+typedef struct jpeg_common_struct * j_common_ptr;

+typedef struct jpeg_compress_struct * j_compress_ptr;

+typedef struct jpeg_decompress_struct * j_decompress_ptr;

+

+

+/* Master record for a compression instance */

+

+struct jpeg_compress_struct {

+  jpeg_common_fields;		/* Fields shared with jpeg_decompress_struct */

+

+  /* Destination for compressed data */

+  struct jpeg_destination_mgr * dest;

+

+  /* Description of source image --- these fields must be filled in by

+   * outer application before starting compression.  in_color_space must

+   * be correct before you can even call jpeg_set_defaults().

+   */

+

+  JDIMENSION image_width;	/* input image width */

+  JDIMENSION image_height;	/* input image height */

+  int input_components;		/* # of color components in input image */

+  J_COLOR_SPACE in_color_space;	/* colorspace of input image */

+

+  double input_gamma;		/* image gamma of input image */

+

+  /* Compression parameters --- these fields must be set before calling

+   * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to

+   * initialize everything to reasonable defaults, then changing anything

+   * the application specifically wants to change.  That way you won't get

+   * burnt when new parameters are added.  Also note that there are several

+   * helper routines to simplify changing parameters.

+   */

+

+  int data_precision;		/* bits of precision in image data */

+

+  int num_components;		/* # of color components in JPEG image */

+  J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */

+

+  jpeg_component_info * comp_info;

+  /* comp_info[i] describes component that appears i'th in SOF */

+  

+  JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];

+  /* ptrs to coefficient quantization tables, or NULL if not defined */

+  

+  JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];

+  JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];

+  /* ptrs to Huffman coding tables, or NULL if not defined */

+  

+  UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */

+  UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */

+  UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */

+

+  int num_scans;		/* # of entries in scan_info array */

+  const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */

+  /* The default value of scan_info is NULL, which causes a single-scan

+   * sequential JPEG file to be emitted.  To create a multi-scan file,

+   * set num_scans and scan_info to point to an array of scan definitions.

+   */

+

+  boolean raw_data_in;		/* TRUE=caller supplies downsampled data */

+  boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */

+  boolean optimize_coding;	/* TRUE=optimize entropy encoding parms */

+  boolean CCIR601_sampling;	/* TRUE=first samples are cosited */

+  int smoothing_factor;		/* 1..100, or 0 for no input smoothing */

+  J_DCT_METHOD dct_method;	/* DCT algorithm selector */

+

+  /* The restart interval can be specified in absolute MCUs by setting

+   * restart_interval, or in MCU rows by setting restart_in_rows

+   * (in which case the correct restart_interval will be figured

+   * for each scan).

+   */

+  unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */

+  int restart_in_rows;		/* if > 0, MCU rows per restart interval */

+

+  /* Parameters controlling emission of special markers. */

+

+  boolean write_JFIF_header;	/* should a JFIF marker be written? */

+  /* These three values are not used by the JPEG code, merely copied */

+  /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */

+  /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */

+  /* ratio is defined by X_density/Y_density even when density_unit=0. */

+  UINT8 density_unit;		/* JFIF code for pixel size units */

+  UINT16 X_density;		/* Horizontal pixel density */

+  UINT16 Y_density;		/* Vertical pixel density */

+  boolean write_Adobe_marker;	/* should an Adobe marker be written? */

+  

+  /* State variable: index of next scanline to be written to

+   * jpeg_write_scanlines().  Application may use this to control its

+   * processing loop, e.g., "while (next_scanline < image_height)".

+   */

+

+  JDIMENSION next_scanline;	/* 0 .. image_height-1  */

+

+  /* Remaining fields are known throughout compressor, but generally

+   * should not be touched by a surrounding application.

+   */

+

+  /*

+   * These fields are computed during compression startup

+   */

+  boolean progressive_mode;	/* TRUE if scan script uses progressive mode */

+  int max_h_samp_factor;	/* largest h_samp_factor */

+  int max_v_samp_factor;	/* largest v_samp_factor */

+

+  JDIMENSION total_iMCU_rows;	/* # of iMCU rows to be input to coef ctlr */

+  /* The coefficient controller receives data in units of MCU rows as defined

+   * for fully interleaved scans (whether the JPEG file is interleaved or not).

+   * There are v_samp_factor * DCTSIZE sample rows of each component in an

+   * "iMCU" (interleaved MCU) row.

+   */

+  

+  /*

+   * These fields are valid during any one scan.

+   * They describe the components and MCUs actually appearing in the scan.

+   */

+  int comps_in_scan;		/* # of JPEG components in this scan */

+  jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];

+  /* *cur_comp_info[i] describes component that appears i'th in SOS */

+  

+  JDIMENSION MCUs_per_row;	/* # of MCUs across the image */

+  JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */

+  

+  int blocks_in_MCU;		/* # of DCT blocks per MCU */

+  int MCU_membership[C_MAX_BLOCKS_IN_MCU];

+  /* MCU_membership[i] is index in cur_comp_info of component owning */

+  /* i'th block in an MCU */

+

+  int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */

+

+  /*

+   * Links to compression subobjects (methods and private variables of modules)

+   */

+  struct jpeg_comp_master * master;

+  struct jpeg_c_main_controller * main;

+  struct jpeg_c_prep_controller * prep;

+  struct jpeg_c_coef_controller * coef;

+  struct jpeg_marker_writer * marker;

+  struct jpeg_color_converter * cconvert;

+  struct jpeg_downsampler * downsample;

+  struct jpeg_forward_dct * fdct;

+  struct jpeg_entropy_encoder * entropy;

+};

+

+

+/* Master record for a decompression instance */

+

+struct jpeg_decompress_struct {

+  jpeg_common_fields;		/* Fields shared with jpeg_compress_struct */

+

+  /* Source of compressed data */

+  struct jpeg_source_mgr * src;

+

+  /* Basic description of image --- filled in by jpeg_read_header(). */

+  /* Application may inspect these values to decide how to process image. */

+

+  JDIMENSION image_width;	/* nominal image width (from SOF marker) */

+  JDIMENSION image_height;	/* nominal image height */

+  int num_components;		/* # of color components in JPEG image */

+  J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */

+

+  /* Decompression processing parameters --- these fields must be set before

+   * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes

+   * them to default values.

+   */

+

+  J_COLOR_SPACE out_color_space; /* colorspace for output */

+

+  unsigned int scale_num, scale_denom; /* fraction by which to scale image */

+

+  double output_gamma;		/* image gamma wanted in output */

+

+  boolean buffered_image;	/* TRUE=multiple output passes */

+  boolean raw_data_out;		/* TRUE=downsampled data wanted */

+

+  J_DCT_METHOD dct_method;	/* IDCT algorithm selector */

+  boolean do_fancy_upsampling;	/* TRUE=apply fancy upsampling */

+  boolean do_block_smoothing;	/* TRUE=apply interblock smoothing */

+

+  boolean quantize_colors;	/* TRUE=colormapped output wanted */

+  /* the following are ignored if not quantize_colors: */

+  J_DITHER_MODE dither_mode;	/* type of color dithering to use */

+  boolean two_pass_quantize;	/* TRUE=use two-pass color quantization */

+  int desired_number_of_colors;	/* max # colors to use in created colormap */

+  /* these are significant only in buffered-image mode: */

+  boolean enable_1pass_quant;	/* enable future use of 1-pass quantizer */

+  boolean enable_external_quant;/* enable future use of external colormap */

+  boolean enable_2pass_quant;	/* enable future use of 2-pass quantizer */

+

+  /* Description of actual output image that will be returned to application.

+   * These fields are computed by jpeg_start_decompress().

+   * You can also use jpeg_calc_output_dimensions() to determine these values

+   * in advance of calling jpeg_start_decompress().

+   */

+

+  JDIMENSION output_width;	/* scaled image width */

+  JDIMENSION output_height;	/* scaled image height */

+  int out_color_components;	/* # of color components in out_color_space */

+  int output_components;	/* # of color components returned */

+  /* output_components is 1 (a colormap index) when quantizing colors;

+   * otherwise it equals out_color_components.

+   */

+  int rec_outbuf_height;	/* min recommended height of scanline buffer */

+  /* If the buffer passed to jpeg_read_scanlines() is less than this many rows

+   * high, space and time will be wasted due to unnecessary data copying.

+   * Usually rec_outbuf_height will be 1 or 2, at most 4.

+   */

+

+  /* When quantizing colors, the output colormap is described by these fields.

+   * The application can supply a colormap by setting colormap non-NULL before

+   * calling jpeg_start_decompress; otherwise a colormap is created during

+   * jpeg_start_decompress or jpeg_start_output.

+   * The map has out_color_components rows and actual_number_of_colors columns.

+   */

+  int actual_number_of_colors;	/* number of entries in use */

+  JSAMPARRAY colormap;		/* The color map as a 2-D pixel array */

+

+  /* State variables: these variables indicate the progress of decompression.

+   * The application may examine these but must not modify them.

+   */

+

+  /* Row index of next scanline to be read from jpeg_read_scanlines().

+   * Application may use this to control its processing loop, e.g.,

+   * "while (output_scanline < output_height)".

+   */

+  JDIMENSION output_scanline;	/* 0 .. output_height-1  */

+

+  /* Current input scan number and number of iMCU rows completed in scan.

+   * These indicate the progress of the decompressor input side.

+   */

+  int input_scan_number;	/* Number of SOS markers seen so far */

+  JDIMENSION input_iMCU_row;	/* Number of iMCU rows completed */

+

+  /* The "output scan number" is the notional scan being displayed by the

+   * output side.  The decompressor will not allow output scan/row number

+   * to get ahead of input scan/row, but it can fall arbitrarily far behind.

+   */

+  int output_scan_number;	/* Nominal scan number being displayed */

+  JDIMENSION output_iMCU_row;	/* Number of iMCU rows read */

+

+  /* Current progression status.  coef_bits[c][i] indicates the precision

+   * with which component c's DCT coefficient i (in zigzag order) is known.

+   * It is -1 when no data has yet been received, otherwise it is the point

+   * transform (shift) value for the most recent scan of the coefficient

+   * (thus, 0 at completion of the progression).

+   * This pointer is NULL when reading a non-progressive file.

+   */

+  int (*coef_bits)[DCTSIZE2];	/* -1 or current Al value for each coef */

+

+  /* Internal JPEG parameters --- the application usually need not look at

+   * these fields.  Note that the decompressor output side may not use

+   * any parameters that can change between scans.

+   */

+

+  /* Quantization and Huffman tables are carried forward across input

+   * datastreams when processing abbreviated JPEG datastreams.

+   */

+

+  JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];

+  /* ptrs to coefficient quantization tables, or NULL if not defined */

+

+  JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];

+  JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];

+  /* ptrs to Huffman coding tables, or NULL if not defined */

+

+  /* These parameters are never carried across datastreams, since they

+   * are given in SOF/SOS markers or defined to be reset by SOI.

+   */

+

+  int data_precision;		/* bits of precision in image data */

+

+  jpeg_component_info * comp_info;

+  /* comp_info[i] describes component that appears i'th in SOF */

+

+  boolean progressive_mode;	/* TRUE if SOFn specifies progressive mode */

+  boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */

+

+  UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */

+  UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */

+  UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */

+

+  unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */

+

+  /* These fields record data obtained from optional markers recognized by

+   * the JPEG library.

+   */

+  boolean saw_JFIF_marker;	/* TRUE iff a JFIF APP0 marker was found */

+  /* Data copied from JFIF marker: */

+  UINT8 density_unit;		/* JFIF code for pixel size units */

+  UINT16 X_density;		/* Horizontal pixel density */

+  UINT16 Y_density;		/* Vertical pixel density */

+  boolean saw_Adobe_marker;	/* TRUE iff an Adobe APP14 marker was found */

+  UINT8 Adobe_transform;	/* Color transform code from Adobe marker */

+

+  boolean CCIR601_sampling;	/* TRUE=first samples are cosited */

+

+  /* Remaining fields are known throughout decompressor, but generally

+   * should not be touched by a surrounding application.

+   */

+

+  /*

+   * These fields are computed during decompression startup

+   */

+  int max_h_samp_factor;	/* largest h_samp_factor */

+  int max_v_samp_factor;	/* largest v_samp_factor */

+

+  int min_DCT_scaled_size;	/* smallest DCT_scaled_size of any component */

+

+  JDIMENSION total_iMCU_rows;	/* # of iMCU rows in image */

+  /* The coefficient controller's input and output progress is measured in

+   * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows

+   * in fully interleaved JPEG scans, but are used whether the scan is

+   * interleaved or not.  We define an iMCU row as v_samp_factor DCT block

+   * rows of each component.  Therefore, the IDCT output contains

+   * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.

+   */

+

+  JSAMPLE * sample_range_limit; /* table for fast range-limiting */

+

+  /*

+   * These fields are valid during any one scan.

+   * They describe the components and MCUs actually appearing in the scan.

+   * Note that the decompressor output side must not use these fields.

+   */

+  int comps_in_scan;		/* # of JPEG components in this scan */

+  jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];

+  /* *cur_comp_info[i] describes component that appears i'th in SOS */

+

+  JDIMENSION MCUs_per_row;	/* # of MCUs across the image */

+  JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */

+

+  int blocks_in_MCU;		/* # of DCT blocks per MCU */

+  int MCU_membership[D_MAX_BLOCKS_IN_MCU];

+  /* MCU_membership[i] is index in cur_comp_info of component owning */

+  /* i'th block in an MCU */

+

+  int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */

+

+  /* This field is shared between entropy decoder and marker parser.

+   * It is either zero or the code of a JPEG marker that has been

+   * read from the data source, but has not yet been processed.

+   */

+  int unread_marker;

+

+  /*

+   * Links to decompression subobjects (methods, private variables of modules)

+   */

+  struct jpeg_decomp_master * master;

+  struct jpeg_d_main_controller * main;

+  struct jpeg_d_coef_controller * coef;

+  struct jpeg_d_post_controller * post;

+  struct jpeg_input_controller * inputctl;

+  struct jpeg_marker_reader * marker;

+  struct jpeg_entropy_decoder * entropy;

+  struct jpeg_inverse_dct * idct;

+  struct jpeg_upsampler * upsample;

+  struct jpeg_color_deconverter * cconvert;

+  struct jpeg_color_quantizer * cquantize;

+};

+

+

+/* "Object" declarations for JPEG modules that may be supplied or called

+ * directly by the surrounding application.

+ * As with all objects in the JPEG library, these structs only define the

+ * publicly visible methods and state variables of a module.  Additional

+ * private fields may exist after the public ones.

+ */

+

+

+/* Error handler object */

+

+struct jpeg_error_mgr {

+  /* Error exit handler: does not return to caller */

+  JMETHOD(void, error_exit, (j_common_ptr cinfo));

+  /* Conditionally emit a trace or warning message */

+  JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));

+  /* Routine that actually outputs a trace or error message */

+  JMETHOD(void, output_message, (j_common_ptr cinfo));

+  /* Format a message string for the most recent JPEG error or message */

+  JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));

+#define JMSG_LENGTH_MAX  200	/* recommended size of format_message buffer */

+  /* Reset error state variables at start of a new image */

+  JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));

+  

+  /* The message ID code and any parameters are saved here.

+   * A message can have one string parameter or up to 8 int parameters.

+   */

+  int msg_code;

+#define JMSG_STR_PARM_MAX  80

+  union {

+    int i[8];

+    char s[JMSG_STR_PARM_MAX];

+  } msg_parm;

+  

+  /* Standard state variables for error facility */

+  

+  int trace_level;		/* max msg_level that will be displayed */

+  

+  /* For recoverable corrupt-data errors, we emit a warning message,

+   * but keep going unless emit_message chooses to abort.  emit_message

+   * should count warnings in num_warnings.  The surrounding application

+   * can check for bad data by seeing if num_warnings is nonzero at the

+   * end of processing.

+   */

+  long num_warnings;		/* number of corrupt-data warnings */

+

+  /* These fields point to the table(s) of error message strings.

+   * An application can change the table pointer to switch to a different

+   * message list (typically, to change the language in which errors are

+   * reported).  Some applications may wish to add additional error codes

+   * that will be handled by the JPEG library error mechanism; the second

+   * table pointer is used for this purpose.

+   *

+   * First table includes all errors generated by JPEG library itself.

+   * Error code 0 is reserved for a "no such error string" message.

+   */

+  const char * const * jpeg_message_table; /* Library errors */

+  int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */

+  /* Second table can be added by application (see cjpeg/djpeg for example).

+   * It contains strings numbered first_addon_message..last_addon_message.

+   */

+  const char * const * addon_message_table; /* Non-library errors */

+  int first_addon_message;	/* code for first string in addon table */

+  int last_addon_message;	/* code for last string in addon table */

+};

+

+

+/* Progress monitor object */

+

+struct jpeg_progress_mgr {

+  JMETHOD(void, progress_monitor, (j_common_ptr cinfo));

+

+  long pass_counter;		/* work units completed in this pass */

+  long pass_limit;		/* total number of work units in this pass */

+  int completed_passes;		/* passes completed so far */

+  int total_passes;		/* total number of passes expected */

+};

+

+

+/* Data destination object for compression */

+

+struct jpeg_destination_mgr {

+  JOCTET * next_output_byte;	/* => next byte to write in buffer */

+  size_t free_in_buffer;	/* # of byte spaces remaining in buffer */

+

+  JMETHOD(void, init_destination, (j_compress_ptr cinfo));

+  JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));

+  JMETHOD(void, term_destination, (j_compress_ptr cinfo));

+};

+

+

+/* Data source object for decompression */

+

+struct jpeg_source_mgr {

+  const JOCTET * next_input_byte; /* => next byte to read from buffer */

+  size_t bytes_in_buffer;	/* # of bytes remaining in buffer */

+

+  JMETHOD(void, init_source, (j_decompress_ptr cinfo));

+  JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));

+  JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));

+  JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));

+  JMETHOD(void, term_source, (j_decompress_ptr cinfo));

+};

+

+

+/* Memory manager object.

+ * Allocates "small" objects (a few K total), "large" objects (tens of K),

+ * and "really big" objects (virtual arrays with backing store if needed).

+ * The memory manager does not allow individual objects to be freed; rather,

+ * each created object is assigned to a pool, and whole pools can be freed

+ * at once.  This is faster and more convenient than remembering exactly what

+ * to free, especially where malloc()/free() are not too speedy.

+ * NB: alloc routines never return NULL.  They exit to error_exit if not

+ * successful.

+ */

+

+#define JPOOL_PERMANENT	0	/* lasts until master record is destroyed */

+#define JPOOL_IMAGE	1	/* lasts until done with image/datastream */

+#define JPOOL_NUMPOOLS	2

+

+typedef struct jvirt_sarray_control * jvirt_sarray_ptr;

+typedef struct jvirt_barray_control * jvirt_barray_ptr;

+

+

+struct jpeg_memory_mgr {

+  /* Method pointers */

+  JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,

+				size_t sizeofobject));

+  JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,

+				     size_t sizeofobject));

+  JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,

+				     JDIMENSION samplesperrow,

+				     JDIMENSION numrows));

+  JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,

+				      JDIMENSION blocksperrow,

+				      JDIMENSION numrows));

+  JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,

+						  int pool_id,

+						  boolean pre_zero,

+						  JDIMENSION samplesperrow,

+						  JDIMENSION numrows,

+						  JDIMENSION maxaccess));

+  JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,

+						  int pool_id,

+						  boolean pre_zero,

+						  JDIMENSION blocksperrow,

+						  JDIMENSION numrows,

+						  JDIMENSION maxaccess));

+  JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));

+  JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,

+					   jvirt_sarray_ptr ptr,

+					   JDIMENSION start_row,

+					   JDIMENSION num_rows,

+					   boolean writable));

+  JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,

+					    jvirt_barray_ptr ptr,

+					    JDIMENSION start_row,

+					    JDIMENSION num_rows,

+					    boolean writable));

+  JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));

+  JMETHOD(void, self_destruct, (j_common_ptr cinfo));

+

+  /* Limit on memory allocation for this JPEG object.  (Note that this is

+   * merely advisory, not a guaranteed maximum; it only affects the space

+   * used for virtual-array buffers.)  May be changed by outer application

+   * after creating the JPEG object.

+   */

+  long max_memory_to_use;

+};

+

+

+/* Routine signature for application-supplied marker processing methods.

+ * Need not pass marker code since it is stored in cinfo->unread_marker.

+ */

+typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));

+

+

+/* Declarations for routines called by application.

+ * The JPP macro hides prototype parameters from compilers that can't cope.

+ * Note JPP requires double parentheses.

+ */

+

+#ifdef HAVE_PROTOTYPES

+#define JPP(arglist)	arglist

+#else

+#define JPP(arglist)	()

+#endif

+

+

+/* Short forms of external names for systems with brain-damaged linkers.

+ * We shorten external names to be unique in the first six letters, which

+ * is good enough for all known systems.

+ * (If your compiler itself needs names to be unique in less than 15 

+ * characters, you are out of luck.  Get a better compiler.)

+ */

+

+#ifdef NEED_SHORT_EXTERNAL_NAMES

+#define jpeg_std_error		jStdError

+#define jpeg_create_compress	jCreaCompress

+#define jpeg_create_decompress	jCreaDecompress

+#define jpeg_destroy_compress	jDestCompress

+#define jpeg_destroy_decompress	jDestDecompress

+#define jpeg_stdio_dest		jStdDest

+#define jpeg_stdio_src		jStdSrc

+#define jpeg_set_defaults	jSetDefaults

+#define jpeg_set_colorspace	jSetColorspace

+#define jpeg_default_colorspace	jDefColorspace

+#define jpeg_set_quality	jSetQuality

+#define jpeg_set_linear_quality	jSetLQuality

+#define jpeg_add_quant_table	jAddQuantTable

+#define jpeg_quality_scaling	jQualityScaling

+#define jpeg_simple_progression	jSimProgress

+#define jpeg_suppress_tables	jSuppressTables

+#define jpeg_alloc_quant_table	jAlcQTable

+#define jpeg_alloc_huff_table	jAlcHTable

+#define jpeg_start_compress	jStrtCompress

+#define jpeg_write_scanlines	jWrtScanlines

+#define jpeg_finish_compress	jFinCompress

+#define jpeg_write_raw_data	jWrtRawData

+#define jpeg_write_marker	jWrtMarker

+#define jpeg_write_tables	jWrtTables

+#define jpeg_read_header	jReadHeader

+#define jpeg_start_decompress	jStrtDecompress

+#define jpeg_read_scanlines	jReadScanlines

+#define jpeg_finish_decompress	jFinDecompress

+#define jpeg_read_raw_data	jReadRawData

+#define jpeg_has_multiple_scans	jHasMultScn

+#define jpeg_start_output	jStrtOutput

+#define jpeg_finish_output	jFinOutput

+#define jpeg_input_complete	jInComplete

+#define jpeg_new_colormap	jNewCMap

+#define jpeg_consume_input	jConsumeInput

+#define jpeg_calc_output_dimensions	jCalcDimensions

+#define jpeg_set_marker_processor	jSetMarker

+#define jpeg_read_coefficients	jReadCoefs

+#define jpeg_write_coefficients	jWrtCoefs

+#define jpeg_copy_critical_parameters	jCopyCrit

+#define jpeg_abort_compress	jAbrtCompress

+#define jpeg_abort_decompress	jAbrtDecompress

+#define jpeg_abort		jAbort

+#define jpeg_destroy		jDestroy

+#define jpeg_resync_to_restart	jResyncRestart

+#endif /* NEED_SHORT_EXTERNAL_NAMES */

+

+

+/* Default error-management setup */

+EXTERN struct jpeg_error_mgr *jpeg_std_error JPP((struct jpeg_error_mgr *err));

+

+/* Initialization and destruction of JPEG compression objects */

+/* NB: you must set up the error-manager BEFORE calling jpeg_create_xxx */

+EXTERN void jpeg_create_compress JPP((j_compress_ptr cinfo));

+EXTERN void jpeg_create_decompress JPP((j_decompress_ptr cinfo));

+EXTERN void jpeg_destroy_compress JPP((j_compress_ptr cinfo));

+EXTERN void jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));

+

+/* Standard data source and destination managers: stdio streams. */

+/* Caller is responsible for opening the file before and closing after. */

+EXTERN void jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));

+EXTERN void jpeg_stdio_src JPP((j_decompress_ptr cinfo, unsigned char *infile));

+

+/* Default parameter setup for compression */

+EXTERN void jpeg_set_defaults JPP((j_compress_ptr cinfo));

+/* Compression parameter setup aids */

+EXTERN void jpeg_set_colorspace JPP((j_compress_ptr cinfo,

+				     J_COLOR_SPACE colorspace));

+EXTERN void jpeg_default_colorspace JPP((j_compress_ptr cinfo));

+EXTERN void jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,

+				  boolean force_baseline));

+EXTERN void jpeg_set_linear_quality JPP((j_compress_ptr cinfo,

+					 int scale_factor,

+					 boolean force_baseline));

+EXTERN void jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,

+				      const unsigned int *basic_table,

+				      int scale_factor,

+				      boolean force_baseline));

+EXTERN int jpeg_quality_scaling JPP((int quality));

+EXTERN void jpeg_simple_progression JPP((j_compress_ptr cinfo));

+EXTERN void jpeg_suppress_tables JPP((j_compress_ptr cinfo,

+				      boolean suppress));

+EXTERN JQUANT_TBL * jpeg_alloc_quant_table JPP((j_common_ptr cinfo));

+EXTERN JHUFF_TBL * jpeg_alloc_huff_table JPP((j_common_ptr cinfo));

+

+/* Main entry points for compression */

+EXTERN void jpeg_start_compress JPP((j_compress_ptr cinfo,

+				     boolean write_all_tables));

+EXTERN JDIMENSION jpeg_write_scanlines JPP((j_compress_ptr cinfo,

+					    JSAMPARRAY scanlines,

+					    JDIMENSION num_lines));

+EXTERN void jpeg_finish_compress JPP((j_compress_ptr cinfo));

+

+/* Replaces jpeg_write_scanlines when writing raw downsampled data. */

+EXTERN JDIMENSION jpeg_write_raw_data JPP((j_compress_ptr cinfo,

+					   JSAMPIMAGE data,

+					   JDIMENSION num_lines));

+

+/* Write a special marker.  See libjpeg.doc concerning safe usage. */

+EXTERN void jpeg_write_marker JPP((j_compress_ptr cinfo, int marker,

+				   const JOCTET *dataptr, unsigned int datalen));

+

+/* Alternate compression function: just write an abbreviated table file */

+EXTERN void jpeg_write_tables JPP((j_compress_ptr cinfo));

+

+/* Decompression startup: read start of JPEG datastream to see what's there */

+EXTERN int jpeg_read_header JPP((j_decompress_ptr cinfo,

+				 boolean require_image));

+/* Return value is one of: */

+#define JPEG_SUSPENDED		0 /* Suspended due to lack of input data */

+#define JPEG_HEADER_OK		1 /* Found valid image datastream */

+#define JPEG_HEADER_TABLES_ONLY	2 /* Found valid table-specs-only datastream */

+/* If you pass require_image = TRUE (normal case), you need not check for

+ * a TABLES_ONLY return code; an abbreviated file will cause an error exit.

+ * JPEG_SUSPENDED is only possible if you use a data source module that can

+ * give a suspension return (the stdio source module doesn't).

+ */

+

+/* Main entry points for decompression */

+EXTERN boolean jpeg_start_decompress JPP((j_decompress_ptr cinfo));

+EXTERN JDIMENSION jpeg_read_scanlines JPP((j_decompress_ptr cinfo,

+					   JSAMPARRAY scanlines,

+					   JDIMENSION max_lines));

+EXTERN boolean jpeg_finish_decompress JPP((j_decompress_ptr cinfo));

+

+/* Replaces jpeg_read_scanlines when reading raw downsampled data. */

+EXTERN JDIMENSION jpeg_read_raw_data JPP((j_decompress_ptr cinfo,

+					  JSAMPIMAGE data,

+					  JDIMENSION max_lines));

+

+/* Additional entry points for buffered-image mode. */

+EXTERN boolean jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));

+EXTERN boolean jpeg_start_output JPP((j_decompress_ptr cinfo,

+				      int scan_number));

+EXTERN boolean jpeg_finish_output JPP((j_decompress_ptr cinfo));

+EXTERN boolean jpeg_input_complete JPP((j_decompress_ptr cinfo));

+EXTERN void jpeg_new_colormap JPP((j_decompress_ptr cinfo));

+EXTERN int jpeg_consume_input JPP((j_decompress_ptr cinfo));

+/* Return value is one of: */

+/* #define JPEG_SUSPENDED	0    Suspended due to lack of input data */

+#define JPEG_REACHED_SOS	1 /* Reached start of new scan */

+#define JPEG_REACHED_EOI	2 /* Reached end of image */

+#define JPEG_ROW_COMPLETED	3 /* Completed one iMCU row */

+#define JPEG_SCAN_COMPLETED	4 /* Completed last iMCU row of a scan */

+

+/* Precalculate output dimensions for current decompression parameters. */

+EXTERN void jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));

+

+/* Install a special processing method for COM or APPn markers. */

+EXTERN void jpeg_set_marker_processor JPP((j_decompress_ptr cinfo,

+					   int marker_code,

+					   jpeg_marker_parser_method routine));

+

+/* Read or write raw DCT coefficients --- useful for lossless transcoding. */

+EXTERN jvirt_barray_ptr * jpeg_read_coefficients JPP((j_decompress_ptr cinfo));

+EXTERN void jpeg_write_coefficients JPP((j_compress_ptr cinfo,

+					 jvirt_barray_ptr * coef_arrays));

+EXTERN void jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,

+					       j_compress_ptr dstinfo));

+

+/* If you choose to abort compression or decompression before completing

+ * jpeg_finish_(de)compress, then you need to clean up to release memory,

+ * temporary files, etc.  You can just call jpeg_destroy_(de)compress

+ * if you're done with the JPEG object, but if you want to clean it up and

+ * reuse it, call this:

+ */

+EXTERN void jpeg_abort_compress JPP((j_compress_ptr cinfo));

+EXTERN void jpeg_abort_decompress JPP((j_decompress_ptr cinfo));

+

+/* Generic versions of jpeg_abort and jpeg_destroy that work on either

+ * flavor of JPEG object.  These may be more convenient in some places.

+ */

+EXTERN void jpeg_abort JPP((j_common_ptr cinfo));

+EXTERN void jpeg_destroy JPP((j_common_ptr cinfo));

+

+/* Default restart-marker-resync procedure for use by data source modules */

+EXTERN boolean jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,

+					   int desired));

+

+

+/* These marker codes are exported since applications and data source modules

+ * are likely to want to use them.

+ */

+

+#define JPEG_RST0	0xD0	/* RST0 marker code */

+#define JPEG_EOI	0xD9	/* EOI marker code */

+#define JPEG_APP0	0xE0	/* APP0 marker code */

+#define JPEG_COM	0xFE	/* COM marker code */

+

+

+/* If we have a brain-damaged compiler that emits warnings (or worse, errors)

+ * for structure definitions that are never filled in, keep it quiet by

+ * supplying dummy definitions for the various substructures.

+ */

+

+#ifdef INCOMPLETE_TYPES_BROKEN

+#ifndef JPEG_INTERNALS		/* will be defined in jpegint.h */

+struct jvirt_sarray_control { long dummy; };

+struct jvirt_barray_control { long dummy; };

+struct jpeg_comp_master { long dummy; };

+struct jpeg_c_main_controller { long dummy; };

+struct jpeg_c_prep_controller { long dummy; };

+struct jpeg_c_coef_controller { long dummy; };

+struct jpeg_marker_writer { long dummy; };

+struct jpeg_color_converter { long dummy; };

+struct jpeg_downsampler { long dummy; };

+struct jpeg_forward_dct { long dummy; };

+struct jpeg_entropy_encoder { long dummy; };

+struct jpeg_decomp_master { long dummy; };

+struct jpeg_d_main_controller { long dummy; };

+struct jpeg_d_coef_controller { long dummy; };

+struct jpeg_d_post_controller { long dummy; };

+struct jpeg_input_controller { long dummy; };

+struct jpeg_marker_reader { long dummy; };

+struct jpeg_entropy_decoder { long dummy; };

+struct jpeg_inverse_dct { long dummy; };

+struct jpeg_upsampler { long dummy; };

+struct jpeg_color_deconverter { long dummy; };

+struct jpeg_color_quantizer { long dummy; };

+#endif /* JPEG_INTERNALS */

+#endif /* INCOMPLETE_TYPES_BROKEN */

+

+

+/*

+ * The JPEG library modules define JPEG_INTERNALS before including this file.

+ * The internal structure declarations are read only when that is true.

+ * Applications using the library should not include jpegint.h, but may wish

+ * to include jerror.h.

+ */

+

+#ifdef JPEG_INTERNALS

+#include "../jpeg-6/jpegint.h"		/* fetch private declarations */

+#include "../jpeg-6/jerror.h"		/* fetch error codes too */

+#endif

+

+#endif /* JPEGLIB_H */

diff --git a/code/jpeg-6/jpegtran.c b/code/jpeg-6/jpegtran.c
new file mode 100755
index 0000000..f23a4b4
--- /dev/null
+++ b/code/jpeg-6/jpegtran.c
@@ -0,0 +1,370 @@
+/*

+ * jpegtran.c

+ *

+ * Copyright (C) 1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains a command-line user interface for JPEG transcoding.

+ * It is very similar to cjpeg.c, but provides lossless transcoding between

+ * different JPEG file formats.

+ */

+

+#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */

+#include "jversion.h"		/* for version message */

+

+#ifdef USE_CCOMMAND		/* command-line reader for Macintosh */

+#ifdef __MWERKS__

+#include <SIOUX.h>              /* Metrowerks declares it here */

+#endif

+#ifdef THINK_C

+#include <console.h>		/* Think declares it here */

+#endif

+#endif

+

+

+/*

+ * Argument-parsing code.

+ * The switch parser is designed to be useful with DOS-style command line

+ * syntax, ie, intermixed switches and file names, where only the switches

+ * to the left of a given file name affect processing of that file.

+ * The main program in this file doesn't actually use this capability...

+ */

+

+

+static const char * progname;	/* program name for error messages */

+static char * outfilename;	/* for -outfile switch */

+

+

+LOCAL void

+usage (void)

+/* complain about bad command line */

+{

+  fprintf(stderr, "usage: %s [switches] ", progname);

+#ifdef TWO_FILE_COMMANDLINE

+  fprintf(stderr, "inputfile outputfile\n");

+#else

+  fprintf(stderr, "[inputfile]\n");

+#endif

+

+  fprintf(stderr, "Switches (names may be abbreviated):\n");

+#ifdef ENTROPY_OPT_SUPPORTED

+  fprintf(stderr, "  -optimize      Optimize Huffman table (smaller file, but slow compression)\n");

+#endif

+#ifdef C_PROGRESSIVE_SUPPORTED

+  fprintf(stderr, "  -progressive   Create progressive JPEG file\n");

+#endif

+  fprintf(stderr, "Switches for advanced users:\n");

+  fprintf(stderr, "  -restart N     Set restart interval in rows, or in blocks with B\n");

+  fprintf(stderr, "  -maxmemory N   Maximum memory to use (in kbytes)\n");

+  fprintf(stderr, "  -outfile name  Specify name for output file\n");

+  fprintf(stderr, "  -verbose  or  -debug   Emit debug output\n");

+  fprintf(stderr, "Switches for wizards:\n");

+#ifdef C_ARITH_CODING_SUPPORTED

+  fprintf(stderr, "  -arithmetic    Use arithmetic coding\n");

+#endif

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+  fprintf(stderr, "  -scans file    Create multi-scan JPEG per script file\n");

+#endif

+  exit(EXIT_FAILURE);

+}

+

+

+LOCAL int

+parse_switches (j_compress_ptr cinfo, int argc, char **argv,

+		int last_file_arg_seen, boolean for_real)

+/* Parse optional switches.

+ * Returns argv[] index of first file-name argument (== argc if none).

+ * Any file names with indexes <= last_file_arg_seen are ignored;

+ * they have presumably been processed in a previous iteration.

+ * (Pass 0 for last_file_arg_seen on the first or only iteration.)

+ * for_real is FALSE on the first (dummy) pass; we may skip any expensive

+ * processing.

+ */

+{

+  int argn;

+  char * arg;

+  boolean simple_progressive;

+  char * scansarg = NULL;	/* saves -scans parm if any */

+

+  /* Set up default JPEG parameters. */

+  simple_progressive = FALSE;

+  outfilename = NULL;

+  cinfo->err->trace_level = 0;

+

+  /* Scan command line options, adjust parameters */

+

+  for (argn = 1; argn < argc; argn++) {

+    arg = argv[argn];

+    if (*arg != '-') {

+      /* Not a switch, must be a file name argument */

+      if (argn <= last_file_arg_seen) {

+	outfilename = NULL;	/* -outfile applies to just one input file */

+	continue;		/* ignore this name if previously processed */

+      }

+      break;			/* else done parsing switches */

+    }

+    arg++;			/* advance past switch marker character */

+

+    if (keymatch(arg, "arithmetic", 1)) {

+      /* Use arithmetic coding. */

+#ifdef C_ARITH_CODING_SUPPORTED

+      cinfo->arith_code = TRUE;

+#else

+      fprintf(stderr, "%s: sorry, arithmetic coding not supported\n",

+	      progname);

+      exit(EXIT_FAILURE);

+#endif

+

+    } else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {

+      /* Enable debug printouts. */

+      /* On first -d, print version identification */

+      static boolean printed_version = FALSE;

+

+      if (! printed_version) {

+	fprintf(stderr, "Independent JPEG Group's JPEGTRAN, version %s\n%s\n",

+		JVERSION, JCOPYRIGHT);

+	printed_version = TRUE;

+      }

+      cinfo->err->trace_level++;

+

+    } else if (keymatch(arg, "maxmemory", 3)) {

+      /* Maximum memory in Kb (or Mb with 'm'). */

+      long lval;

+      char ch = 'x';

+

+      if (++argn >= argc)	/* advance to next argument */

+	usage();

+      if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)

+	usage();

+      if (ch == 'm' || ch == 'M')

+	lval *= 1000L;

+      cinfo->mem->max_memory_to_use = lval * 1000L;

+

+    } else if (keymatch(arg, "optimize", 1) || keymatch(arg, "optimise", 1)) {

+      /* Enable entropy parm optimization. */

+#ifdef ENTROPY_OPT_SUPPORTED

+      cinfo->optimize_coding = TRUE;

+#else

+      fprintf(stderr, "%s: sorry, entropy optimization was not compiled\n",

+	      progname);

+      exit(EXIT_FAILURE);

+#endif

+

+    } else if (keymatch(arg, "outfile", 4)) {

+      /* Set output file name. */

+      if (++argn >= argc)	/* advance to next argument */

+	usage();

+      outfilename = argv[argn];	/* save it away for later use */

+

+    } else if (keymatch(arg, "progressive", 1)) {

+      /* Select simple progressive mode. */

+#ifdef C_PROGRESSIVE_SUPPORTED

+      simple_progressive = TRUE;

+      /* We must postpone execution until num_components is known. */

+#else

+      fprintf(stderr, "%s: sorry, progressive output was not compiled\n",

+	      progname);

+      exit(EXIT_FAILURE);

+#endif

+

+    } else if (keymatch(arg, "restart", 1)) {

+      /* Restart interval in MCU rows (or in MCUs with 'b'). */

+      long lval;

+      char ch = 'x';

+

+      if (++argn >= argc)	/* advance to next argument */

+	usage();

+      if (sscanf(argv[argn], "%ld%c", &lval, &ch) < 1)

+	usage();

+      if (lval < 0 || lval > 65535L)

+	usage();

+      if (ch == 'b' || ch == 'B') {

+	cinfo->restart_interval = (unsigned int) lval;

+	cinfo->restart_in_rows = 0; /* else prior '-restart n' overrides me */

+      } else {

+	cinfo->restart_in_rows = (int) lval;

+	/* restart_interval will be computed during startup */

+      }

+

+    } else if (keymatch(arg, "scans", 2)) {

+      /* Set scan script. */

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+      if (++argn >= argc)	/* advance to next argument */

+	usage();

+      scansarg = argv[argn];

+      /* We must postpone reading the file in case -progressive appears. */

+#else

+      fprintf(stderr, "%s: sorry, multi-scan output was not compiled\n",

+	      progname);

+      exit(EXIT_FAILURE);

+#endif

+

+    } else {

+      usage();			/* bogus switch */

+    }

+  }

+

+  /* Post-switch-scanning cleanup */

+

+  if (for_real) {

+

+#ifdef C_PROGRESSIVE_SUPPORTED

+    if (simple_progressive)	/* process -progressive; -scans can override */

+      jpeg_simple_progression(cinfo);

+#endif

+

+#ifdef C_MULTISCAN_FILES_SUPPORTED

+    if (scansarg != NULL)	/* process -scans if it was present */

+      if (! read_scan_script(cinfo, scansarg))

+	usage();

+#endif

+  }

+

+  return argn;			/* return index of next arg (file name) */

+}

+

+

+/*

+ * The main program.

+ */

+

+GLOBAL int

+main (int argc, char **argv)

+{

+  struct jpeg_decompress_struct srcinfo;

+  struct jpeg_compress_struct dstinfo;

+  struct jpeg_error_mgr jsrcerr, jdsterr;

+#ifdef PROGRESS_REPORT

+  struct cdjpeg_progress_mgr progress;

+#endif

+  jvirt_barray_ptr * coef_arrays;

+  int file_index;

+  FILE * input_file;

+  FILE * output_file;

+

+  /* On Mac, fetch a command line. */

+#ifdef USE_CCOMMAND

+  argc = ccommand(&argv);

+#endif

+

+  progname = argv[0];

+  if (progname == NULL || progname[0] == 0)

+    progname = "jpegtran";	/* in case C library doesn't provide it */

+

+  /* Initialize the JPEG decompression object with default error handling. */

+  srcinfo.err = jpeg_std_error(&jsrcerr);

+  jpeg_create_decompress(&srcinfo);

+  /* Initialize the JPEG compression object with default error handling. */

+  dstinfo.err = jpeg_std_error(&jdsterr);

+  jpeg_create_compress(&dstinfo);

+

+  /* Now safe to enable signal catcher.

+   * Note: we assume only the decompression object will have virtual arrays.

+   */

+#ifdef NEED_SIGNAL_CATCHER

+  enable_signal_catcher((j_common_ptr) &srcinfo);

+#endif

+

+  /* Scan command line to find file names.

+   * It is convenient to use just one switch-parsing routine, but the switch

+   * values read here are ignored; we will rescan the switches after opening

+   * the input file.

+   */

+

+  file_index = parse_switches(&dstinfo, argc, argv, 0, FALSE);

+  jsrcerr.trace_level = jdsterr.trace_level;

+

+#ifdef TWO_FILE_COMMANDLINE

+  /* Must have either -outfile switch or explicit output file name */

+  if (outfilename == NULL) {

+    if (file_index != argc-2) {

+      fprintf(stderr, "%s: must name one input and one output file\n",

+	      progname);

+      usage();

+    }

+    outfilename = argv[file_index+1];

+  } else {

+    if (file_index != argc-1) {

+      fprintf(stderr, "%s: must name one input and one output file\n",

+	      progname);

+      usage();

+    }

+  }

+#else

+  /* Unix style: expect zero or one file name */

+  if (file_index < argc-1) {

+    fprintf(stderr, "%s: only one input file\n", progname);

+    usage();

+  }

+#endif /* TWO_FILE_COMMANDLINE */

+

+  /* Open the input file. */

+  if (file_index < argc) {

+    if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {

+      fprintf(stderr, "%s: can't open %s\n", progname, argv[file_index]);

+      exit(EXIT_FAILURE);

+    }

+  } else {

+    /* default input file is stdin */

+    input_file = read_stdin();

+  }

+

+  /* Open the output file. */

+  if (outfilename != NULL) {

+    if ((output_file = fopen(outfilename, WRITE_BINARY)) == NULL) {

+      fprintf(stderr, "%s: can't open %s\n", progname, outfilename);

+      exit(EXIT_FAILURE);

+    }

+  } else {

+    /* default output file is stdout */

+    output_file = write_stdout();

+  }

+

+#ifdef PROGRESS_REPORT

+  start_progress_monitor((j_common_ptr) &dstinfo, &progress);

+#endif

+

+  /* Specify data source for decompression */

+  jpeg_stdio_src(&srcinfo, input_file);

+

+  /* Read file header */

+  (void) jpeg_read_header(&srcinfo, TRUE);

+

+  /* Read source file as DCT coefficients */

+  coef_arrays = jpeg_read_coefficients(&srcinfo);

+

+  /* Initialize destination compression parameters from source values */

+  jpeg_copy_critical_parameters(&srcinfo, &dstinfo);

+

+  /* Adjust default compression parameters by re-parsing the options */

+  file_index = parse_switches(&dstinfo, argc, argv, 0, TRUE);

+

+  /* Specify data destination for compression */

+  jpeg_stdio_dest(&dstinfo, output_file);

+

+  /* Start compressor */

+  jpeg_write_coefficients(&dstinfo, coef_arrays);

+

+  /* ought to copy source comments here... */

+

+  /* Finish compression and release memory */

+  jpeg_finish_compress(&dstinfo);

+  jpeg_destroy_compress(&dstinfo);

+  (void) jpeg_finish_decompress(&srcinfo);

+  jpeg_destroy_decompress(&srcinfo);

+

+  /* Close files, if we opened them */

+  if (input_file != stdin)

+    fclose(input_file);

+  if (output_file != stdout)

+    fclose(output_file);

+

+#ifdef PROGRESS_REPORT

+  end_progress_monitor((j_common_ptr) &dstinfo);

+#endif

+

+  /* All done. */

+  exit(jsrcerr.num_warnings + jdsterr.num_warnings ?EXIT_WARNING:EXIT_SUCCESS);

+  return 0;			/* suppress no-return-value warnings */

+}

diff --git a/code/jpeg-6/jquant1.c b/code/jpeg-6/jquant1.c
new file mode 100755
index 0000000..ab7e99c
--- /dev/null
+++ b/code/jpeg-6/jquant1.c
@@ -0,0 +1,856 @@
+/*

+ * jquant1.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains 1-pass color quantization (color mapping) routines.

+ * These routines provide mapping to a fixed color map using equally spaced

+ * color values.  Optional Floyd-Steinberg or ordered dithering is available.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+#ifdef QUANT_1PASS_SUPPORTED

+

+

+/*

+ * The main purpose of 1-pass quantization is to provide a fast, if not very

+ * high quality, colormapped output capability.  A 2-pass quantizer usually

+ * gives better visual quality; however, for quantized grayscale output this

+ * quantizer is perfectly adequate.  Dithering is highly recommended with this

+ * quantizer, though you can turn it off if you really want to.

+ *

+ * In 1-pass quantization the colormap must be chosen in advance of seeing the

+ * image.  We use a map consisting of all combinations of Ncolors[i] color

+ * values for the i'th component.  The Ncolors[] values are chosen so that

+ * their product, the total number of colors, is no more than that requested.

+ * (In most cases, the product will be somewhat less.)

+ *

+ * Since the colormap is orthogonal, the representative value for each color

+ * component can be determined without considering the other components;

+ * then these indexes can be combined into a colormap index by a standard

+ * N-dimensional-array-subscript calculation.  Most of the arithmetic involved

+ * can be precalculated and stored in the lookup table colorindex[].

+ * colorindex[i][j] maps pixel value j in component i to the nearest

+ * representative value (grid plane) for that component; this index is

+ * multiplied by the array stride for component i, so that the

+ * index of the colormap entry closest to a given pixel value is just

+ *    sum( colorindex[component-number][pixel-component-value] )

+ * Aside from being fast, this scheme allows for variable spacing between

+ * representative values with no additional lookup cost.

+ *

+ * If gamma correction has been applied in color conversion, it might be wise

+ * to adjust the color grid spacing so that the representative colors are

+ * equidistant in linear space.  At this writing, gamma correction is not

+ * implemented by jdcolor, so nothing is done here.

+ */

+

+

+/* Declarations for ordered dithering.

+ *

+ * We use a standard 16x16 ordered dither array.  The basic concept of ordered

+ * dithering is described in many references, for instance Dale Schumacher's

+ * chapter II.2 of Graphics Gems II (James Arvo, ed. Academic Press, 1991).

+ * In place of Schumacher's comparisons against a "threshold" value, we add a

+ * "dither" value to the input pixel and then round the result to the nearest

+ * output value.  The dither value is equivalent to (0.5 - threshold) times

+ * the distance between output values.  For ordered dithering, we assume that

+ * the output colors are equally spaced; if not, results will probably be

+ * worse, since the dither may be too much or too little at a given point.

+ *

+ * The normal calculation would be to form pixel value + dither, range-limit

+ * this to 0..MAXJSAMPLE, and then index into the colorindex table as usual.

+ * We can skip the separate range-limiting step by extending the colorindex

+ * table in both directions.

+ */

+

+#define ODITHER_SIZE  16	/* dimension of dither matrix */

+/* NB: if ODITHER_SIZE is not a power of 2, ODITHER_MASK uses will break */

+#define ODITHER_CELLS (ODITHER_SIZE*ODITHER_SIZE)	/* # cells in matrix */

+#define ODITHER_MASK  (ODITHER_SIZE-1) /* mask for wrapping around counters */

+

+typedef int ODITHER_MATRIX[ODITHER_SIZE][ODITHER_SIZE];

+typedef int (*ODITHER_MATRIX_PTR)[ODITHER_SIZE];

+

+static const UINT8 base_dither_matrix[ODITHER_SIZE][ODITHER_SIZE] = {

+  /* Bayer's order-4 dither array.  Generated by the code given in

+   * Stephen Hawley's article "Ordered Dithering" in Graphics Gems I.

+   * The values in this array must range from 0 to ODITHER_CELLS-1.

+   */

+  {   0,192, 48,240, 12,204, 60,252,  3,195, 51,243, 15,207, 63,255 },

+  { 128, 64,176,112,140, 76,188,124,131, 67,179,115,143, 79,191,127 },

+  {  32,224, 16,208, 44,236, 28,220, 35,227, 19,211, 47,239, 31,223 },

+  { 160, 96,144, 80,172,108,156, 92,163, 99,147, 83,175,111,159, 95 },

+  {   8,200, 56,248,  4,196, 52,244, 11,203, 59,251,  7,199, 55,247 },

+  { 136, 72,184,120,132, 68,180,116,139, 75,187,123,135, 71,183,119 },

+  {  40,232, 24,216, 36,228, 20,212, 43,235, 27,219, 39,231, 23,215 },

+  { 168,104,152, 88,164,100,148, 84,171,107,155, 91,167,103,151, 87 },

+  {   2,194, 50,242, 14,206, 62,254,  1,193, 49,241, 13,205, 61,253 },

+  { 130, 66,178,114,142, 78,190,126,129, 65,177,113,141, 77,189,125 },

+  {  34,226, 18,210, 46,238, 30,222, 33,225, 17,209, 45,237, 29,221 },

+  { 162, 98,146, 82,174,110,158, 94,161, 97,145, 81,173,109,157, 93 },

+  {  10,202, 58,250,  6,198, 54,246,  9,201, 57,249,  5,197, 53,245 },

+  { 138, 74,186,122,134, 70,182,118,137, 73,185,121,133, 69,181,117 },

+  {  42,234, 26,218, 38,230, 22,214, 41,233, 25,217, 37,229, 21,213 },

+  { 170,106,154, 90,166,102,150, 86,169,105,153, 89,165,101,149, 85 }

+};

+

+

+/* Declarations for Floyd-Steinberg dithering.

+ *

+ * Errors are accumulated into the array fserrors[], at a resolution of

+ * 1/16th of a pixel count.  The error at a given pixel is propagated

+ * to its not-yet-processed neighbors using the standard F-S fractions,

+ *		...	(here)	7/16

+ *		3/16	5/16	1/16

+ * We work left-to-right on even rows, right-to-left on odd rows.

+ *

+ * We can get away with a single array (holding one row's worth of errors)

+ * by using it to store the current row's errors at pixel columns not yet

+ * processed, but the next row's errors at columns already processed.  We

+ * need only a few extra variables to hold the errors immediately around the

+ * current column.  (If we are lucky, those variables are in registers, but

+ * even if not, they're probably cheaper to access than array elements are.)

+ *

+ * The fserrors[] array is indexed [component#][position].

+ * We provide (#columns + 2) entries per component; the extra entry at each

+ * end saves us from special-casing the first and last pixels.

+ *

+ * Note: on a wide image, we might not have enough room in a PC's near data

+ * segment to hold the error array; so it is allocated with alloc_large.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+typedef INT16 FSERROR;		/* 16 bits should be enough */

+typedef int LOCFSERROR;		/* use 'int' for calculation temps */

+#else

+typedef INT32 FSERROR;		/* may need more than 16 bits */

+typedef INT32 LOCFSERROR;	/* be sure calculation temps are big enough */

+#endif

+

+typedef FSERROR FAR *FSERRPTR;	/* pointer to error array (in FAR storage!) */

+

+

+/* Private subobject */

+

+#define MAX_Q_COMPS 4		/* max components I can handle */

+

+typedef struct {

+  struct jpeg_color_quantizer pub; /* public fields */

+

+  /* Initially allocated colormap is saved here */

+  JSAMPARRAY sv_colormap;	/* The color map as a 2-D pixel array */

+  int sv_actual;		/* number of entries in use */

+

+  JSAMPARRAY colorindex;	/* Precomputed mapping for speed */

+  /* colorindex[i][j] = index of color closest to pixel value j in component i,

+   * premultiplied as described above.  Since colormap indexes must fit into

+   * JSAMPLEs, the entries of this array will too.

+   */

+  boolean is_padded;		/* is the colorindex padded for odither? */

+

+  int Ncolors[MAX_Q_COMPS];	/* # of values alloced to each component */

+

+  /* Variables for ordered dithering */

+  int row_index;		/* cur row's vertical index in dither matrix */

+  ODITHER_MATRIX_PTR odither[MAX_Q_COMPS]; /* one dither array per component */

+

+  /* Variables for Floyd-Steinberg dithering */

+  FSERRPTR fserrors[MAX_Q_COMPS]; /* accumulated errors */

+  boolean on_odd_row;		/* flag to remember which row we are on */

+} my_cquantizer;

+

+typedef my_cquantizer * my_cquantize_ptr;

+

+

+/*

+ * Policy-making subroutines for create_colormap and create_colorindex.

+ * These routines determine the colormap to be used.  The rest of the module

+ * only assumes that the colormap is orthogonal.

+ *

+ *  * select_ncolors decides how to divvy up the available colors

+ *    among the components.

+ *  * output_value defines the set of representative values for a component.

+ *  * largest_input_value defines the mapping from input values to

+ *    representative values for a component.

+ * Note that the latter two routines may impose different policies for

+ * different components, though this is not currently done.

+ */

+

+

+LOCAL int

+select_ncolors (j_decompress_ptr cinfo, int Ncolors[])

+/* Determine allocation of desired colors to components, */

+/* and fill in Ncolors[] array to indicate choice. */

+/* Return value is total number of colors (product of Ncolors[] values). */

+{

+  int nc = cinfo->out_color_components; /* number of color components */

+  int max_colors = cinfo->desired_number_of_colors;

+  int total_colors, iroot, i, j;

+  boolean changed;

+  long temp;

+  static const int RGB_order[3] = { RGB_GREEN, RGB_RED, RGB_BLUE };

+

+  /* We can allocate at least the nc'th root of max_colors per component. */

+  /* Compute floor(nc'th root of max_colors). */

+  iroot = 1;

+  do {

+    iroot++;

+    temp = iroot;		/* set temp = iroot ** nc */

+    for (i = 1; i < nc; i++)

+      temp *= iroot;

+  } while (temp <= (long) max_colors); /* repeat till iroot exceeds root */

+  iroot--;			/* now iroot = floor(root) */

+

+  /* Must have at least 2 color values per component */

+  if (iroot < 2)

+    ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, (int) temp);

+

+  /* Initialize to iroot color values for each component */

+  total_colors = 1;

+  for (i = 0; i < nc; i++) {

+    Ncolors[i] = iroot;

+    total_colors *= iroot;

+  }

+  /* We may be able to increment the count for one or more components without

+   * exceeding max_colors, though we know not all can be incremented.

+   * Sometimes, the first component can be incremented more than once!

+   * (Example: for 16 colors, we start at 2*2*2, go to 3*2*2, then 4*2*2.)

+   * In RGB colorspace, try to increment G first, then R, then B.

+   */

+  do {

+    changed = FALSE;

+    for (i = 0; i < nc; i++) {

+      j = (cinfo->out_color_space == JCS_RGB ? RGB_order[i] : i);

+      /* calculate new total_colors if Ncolors[j] is incremented */

+      temp = total_colors / Ncolors[j];

+      temp *= Ncolors[j]+1;	/* done in long arith to avoid oflo */

+      if (temp > (long) max_colors)

+	break;			/* won't fit, done with this pass */

+      Ncolors[j]++;		/* OK, apply the increment */

+      total_colors = (int) temp;

+      changed = TRUE;

+    }

+  } while (changed);

+

+  return total_colors;

+}

+

+

+LOCAL int

+output_value (j_decompress_ptr cinfo, int ci, int j, int maxj)

+/* Return j'th output value, where j will range from 0 to maxj */

+/* The output values must fall in 0..MAXJSAMPLE in increasing order */

+{

+  /* We always provide values 0 and MAXJSAMPLE for each component;

+   * any additional values are equally spaced between these limits.

+   * (Forcing the upper and lower values to the limits ensures that

+   * dithering can't produce a color outside the selected gamut.)

+   */

+  return (int) (((INT32) j * MAXJSAMPLE + maxj/2) / maxj);

+}

+

+

+LOCAL int

+largest_input_value (j_decompress_ptr cinfo, int ci, int j, int maxj)

+/* Return largest input value that should map to j'th output value */

+/* Must have largest(j=0) >= 0, and largest(j=maxj) >= MAXJSAMPLE */

+{

+  /* Breakpoints are halfway between values returned by output_value */

+  return (int) (((INT32) (2*j + 1) * MAXJSAMPLE + maxj) / (2*maxj));

+}

+

+

+/*

+ * Create the colormap.

+ */

+

+LOCAL void

+create_colormap (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  JSAMPARRAY colormap;		/* Created colormap */

+  int total_colors;		/* Number of distinct output colors */

+  int i,j,k, nci, blksize, blkdist, ptr, val;

+

+  /* Select number of colors for each component */

+  total_colors = select_ncolors(cinfo, cquantize->Ncolors);

+

+  /* Report selected color counts */

+  if (cinfo->out_color_components == 3)

+    TRACEMS4(cinfo, 1, JTRC_QUANT_3_NCOLORS,

+	     total_colors, cquantize->Ncolors[0],

+	     cquantize->Ncolors[1], cquantize->Ncolors[2]);

+  else

+    TRACEMS1(cinfo, 1, JTRC_QUANT_NCOLORS, total_colors);

+

+  /* Allocate and fill in the colormap. */

+  /* The colors are ordered in the map in standard row-major order, */

+  /* i.e. rightmost (highest-indexed) color changes most rapidly. */

+

+  colormap = (*cinfo->mem->alloc_sarray)

+    ((j_common_ptr) cinfo, JPOOL_IMAGE,

+     (JDIMENSION) total_colors, (JDIMENSION) cinfo->out_color_components);

+

+  /* blksize is number of adjacent repeated entries for a component */

+  /* blkdist is distance between groups of identical entries for a component */

+  blkdist = total_colors;

+

+  for (i = 0; i < cinfo->out_color_components; i++) {

+    /* fill in colormap entries for i'th color component */

+    nci = cquantize->Ncolors[i]; /* # of distinct values for this color */

+    blksize = blkdist / nci;

+    for (j = 0; j < nci; j++) {

+      /* Compute j'th output value (out of nci) for component */

+      val = output_value(cinfo, i, j, nci-1);

+      /* Fill in all colormap entries that have this value of this component */

+      for (ptr = j * blksize; ptr < total_colors; ptr += blkdist) {

+	/* fill in blksize entries beginning at ptr */

+	for (k = 0; k < blksize; k++)

+	  colormap[i][ptr+k] = (JSAMPLE) val;

+      }

+    }

+    blkdist = blksize;		/* blksize of this color is blkdist of next */

+  }

+

+  /* Save the colormap in private storage,

+   * where it will survive color quantization mode changes.

+   */

+  cquantize->sv_colormap = colormap;

+  cquantize->sv_actual = total_colors;

+}

+

+

+/*

+ * Create the color index table.

+ */

+

+LOCAL void

+create_colorindex (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  JSAMPROW indexptr;

+  int i,j,k, nci, blksize, val, pad;

+

+  /* For ordered dither, we pad the color index tables by MAXJSAMPLE in

+   * each direction (input index values can be -MAXJSAMPLE .. 2*MAXJSAMPLE).

+   * This is not necessary in the other dithering modes.  However, we

+   * flag whether it was done in case user changes dithering mode.

+   */

+  if (cinfo->dither_mode == JDITHER_ORDERED) {

+    pad = MAXJSAMPLE*2;

+    cquantize->is_padded = TRUE;

+  } else {

+    pad = 0;

+    cquantize->is_padded = FALSE;

+  }

+

+  cquantize->colorindex = (*cinfo->mem->alloc_sarray)

+    ((j_common_ptr) cinfo, JPOOL_IMAGE,

+     (JDIMENSION) (MAXJSAMPLE+1 + pad),

+     (JDIMENSION) cinfo->out_color_components);

+

+  /* blksize is number of adjacent repeated entries for a component */

+  blksize = cquantize->sv_actual;

+

+  for (i = 0; i < cinfo->out_color_components; i++) {

+    /* fill in colorindex entries for i'th color component */

+    nci = cquantize->Ncolors[i]; /* # of distinct values for this color */

+    blksize = blksize / nci;

+

+    /* adjust colorindex pointers to provide padding at negative indexes. */

+    if (pad)

+      cquantize->colorindex[i] += MAXJSAMPLE;

+

+    /* in loop, val = index of current output value, */

+    /* and k = largest j that maps to current val */

+    indexptr = cquantize->colorindex[i];

+    val = 0;

+    k = largest_input_value(cinfo, i, 0, nci-1);

+    for (j = 0; j <= MAXJSAMPLE; j++) {

+      while (j > k)		/* advance val if past boundary */

+	k = largest_input_value(cinfo, i, ++val, nci-1);

+      /* premultiply so that no multiplication needed in main processing */

+      indexptr[j] = (JSAMPLE) (val * blksize);

+    }

+    /* Pad at both ends if necessary */

+    if (pad)

+      for (j = 1; j <= MAXJSAMPLE; j++) {

+	indexptr[-j] = indexptr[0];

+	indexptr[MAXJSAMPLE+j] = indexptr[MAXJSAMPLE];

+      }

+  }

+}

+

+

+/*

+ * Create an ordered-dither array for a component having ncolors

+ * distinct output values.

+ */

+

+LOCAL ODITHER_MATRIX_PTR

+make_odither_array (j_decompress_ptr cinfo, int ncolors)

+{

+  ODITHER_MATRIX_PTR odither;

+  int j,k;

+  INT32 num,den;

+

+  odither = (ODITHER_MATRIX_PTR)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(ODITHER_MATRIX));

+  /* The inter-value distance for this color is MAXJSAMPLE/(ncolors-1).

+   * Hence the dither value for the matrix cell with fill order f

+   * (f=0..N-1) should be (N-1-2*f)/(2*N) * MAXJSAMPLE/(ncolors-1).

+   * On 16-bit-int machine, be careful to avoid overflow.

+   */

+  den = 2 * ODITHER_CELLS * ((INT32) (ncolors - 1));

+  for (j = 0; j < ODITHER_SIZE; j++) {

+    for (k = 0; k < ODITHER_SIZE; k++) {

+      num = ((INT32) (ODITHER_CELLS-1 - 2*((int)base_dither_matrix[j][k])))

+	    * MAXJSAMPLE;

+      /* Ensure round towards zero despite C's lack of consistency

+       * about rounding negative values in integer division...

+       */

+      odither[j][k] = (int) (num<0 ? -((-num)/den) : num/den);

+    }

+  }

+  return odither;

+}

+

+

+/*

+ * Create the ordered-dither tables.

+ * Components having the same number of representative colors may 

+ * share a dither table.

+ */

+

+LOCAL void

+create_odither_tables (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  ODITHER_MATRIX_PTR odither;

+  int i, j, nci;

+

+  for (i = 0; i < cinfo->out_color_components; i++) {

+    nci = cquantize->Ncolors[i]; /* # of distinct values for this color */

+    odither = NULL;		/* search for matching prior component */

+    for (j = 0; j < i; j++) {

+      if (nci == cquantize->Ncolors[j]) {

+	odither = cquantize->odither[j];

+	break;

+      }

+    }

+    if (odither == NULL)	/* need a new table? */

+      odither = make_odither_array(cinfo, nci);

+    cquantize->odither[i] = odither;

+  }

+}

+

+

+/*

+ * Map some rows of pixels to the output colormapped representation.

+ */

+

+METHODDEF void

+color_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		JSAMPARRAY output_buf, int num_rows)

+/* General case, no dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  JSAMPARRAY colorindex = cquantize->colorindex;

+  register int pixcode, ci;

+  register JSAMPROW ptrin, ptrout;

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+  register int nc = cinfo->out_color_components;

+

+  for (row = 0; row < num_rows; row++) {

+    ptrin = input_buf[row];

+    ptrout = output_buf[row];

+    for (col = width; col > 0; col--) {

+      pixcode = 0;

+      for (ci = 0; ci < nc; ci++) {

+	pixcode += GETJSAMPLE(colorindex[ci][GETJSAMPLE(*ptrin++)]);

+      }

+      *ptrout++ = (JSAMPLE) pixcode;

+    }

+  }

+}

+

+

+METHODDEF void

+color_quantize3 (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		 JSAMPARRAY output_buf, int num_rows)

+/* Fast path for out_color_components==3, no dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  register int pixcode;

+  register JSAMPROW ptrin, ptrout;

+  JSAMPROW colorindex0 = cquantize->colorindex[0];

+  JSAMPROW colorindex1 = cquantize->colorindex[1];

+  JSAMPROW colorindex2 = cquantize->colorindex[2];

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+

+  for (row = 0; row < num_rows; row++) {

+    ptrin = input_buf[row];

+    ptrout = output_buf[row];

+    for (col = width; col > 0; col--) {

+      pixcode  = GETJSAMPLE(colorindex0[GETJSAMPLE(*ptrin++)]);

+      pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*ptrin++)]);

+      pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*ptrin++)]);

+      *ptrout++ = (JSAMPLE) pixcode;

+    }

+  }

+}

+

+

+METHODDEF void

+quantize_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		     JSAMPARRAY output_buf, int num_rows)

+/* General case, with ordered dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  register JSAMPROW input_ptr;

+  register JSAMPROW output_ptr;

+  JSAMPROW colorindex_ci;

+  int * dither;			/* points to active row of dither matrix */

+  int row_index, col_index;	/* current indexes into dither matrix */

+  int nc = cinfo->out_color_components;

+  int ci;

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+

+  for (row = 0; row < num_rows; row++) {

+    /* Initialize output values to 0 so can process components separately */

+    jzero_far((void FAR *) output_buf[row],

+	      (size_t) (width * SIZEOF(JSAMPLE)));

+    row_index = cquantize->row_index;

+    for (ci = 0; ci < nc; ci++) {

+      input_ptr = input_buf[row] + ci;

+      output_ptr = output_buf[row];

+      colorindex_ci = cquantize->colorindex[ci];

+      dither = cquantize->odither[ci][row_index];

+      col_index = 0;

+

+      for (col = width; col > 0; col--) {

+	/* Form pixel value + dither, range-limit to 0..MAXJSAMPLE,

+	 * select output value, accumulate into output code for this pixel.

+	 * Range-limiting need not be done explicitly, as we have extended

+	 * the colorindex table to produce the right answers for out-of-range

+	 * inputs.  The maximum dither is +- MAXJSAMPLE; this sets the

+	 * required amount of padding.

+	 */

+	*output_ptr += colorindex_ci[GETJSAMPLE(*input_ptr)+dither[col_index]];

+	input_ptr += nc;

+	output_ptr++;

+	col_index = (col_index + 1) & ODITHER_MASK;

+      }

+    }

+    /* Advance row index for next row */

+    row_index = (row_index + 1) & ODITHER_MASK;

+    cquantize->row_index = row_index;

+  }

+}

+

+

+METHODDEF void

+quantize3_ord_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		      JSAMPARRAY output_buf, int num_rows)

+/* Fast path for out_color_components==3, with ordered dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  register int pixcode;

+  register JSAMPROW input_ptr;

+  register JSAMPROW output_ptr;

+  JSAMPROW colorindex0 = cquantize->colorindex[0];

+  JSAMPROW colorindex1 = cquantize->colorindex[1];

+  JSAMPROW colorindex2 = cquantize->colorindex[2];

+  int * dither0;		/* points to active row of dither matrix */

+  int * dither1;

+  int * dither2;

+  int row_index, col_index;	/* current indexes into dither matrix */

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+

+  for (row = 0; row < num_rows; row++) {

+    row_index = cquantize->row_index;

+    input_ptr = input_buf[row];

+    output_ptr = output_buf[row];

+    dither0 = cquantize->odither[0][row_index];

+    dither1 = cquantize->odither[1][row_index];

+    dither2 = cquantize->odither[2][row_index];

+    col_index = 0;

+

+    for (col = width; col > 0; col--) {

+      pixcode  = GETJSAMPLE(colorindex0[GETJSAMPLE(*input_ptr++) +

+					dither0[col_index]]);

+      pixcode += GETJSAMPLE(colorindex1[GETJSAMPLE(*input_ptr++) +

+					dither1[col_index]]);

+      pixcode += GETJSAMPLE(colorindex2[GETJSAMPLE(*input_ptr++) +

+					dither2[col_index]]);

+      *output_ptr++ = (JSAMPLE) pixcode;

+      col_index = (col_index + 1) & ODITHER_MASK;

+    }

+    row_index = (row_index + 1) & ODITHER_MASK;

+    cquantize->row_index = row_index;

+  }

+}

+

+

+METHODDEF void

+quantize_fs_dither (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		    JSAMPARRAY output_buf, int num_rows)

+/* General case, with Floyd-Steinberg dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  register LOCFSERROR cur;	/* current error or pixel value */

+  LOCFSERROR belowerr;		/* error for pixel below cur */

+  LOCFSERROR bpreverr;		/* error for below/prev col */

+  LOCFSERROR bnexterr;		/* error for below/next col */

+  LOCFSERROR delta;

+  register FSERRPTR errorptr;	/* => fserrors[] at column before current */

+  register JSAMPROW input_ptr;

+  register JSAMPROW output_ptr;

+  JSAMPROW colorindex_ci;

+  JSAMPROW colormap_ci;

+  int pixcode;

+  int nc = cinfo->out_color_components;

+  int dir;			/* 1 for left-to-right, -1 for right-to-left */

+  int dirnc;			/* dir * nc */

+  int ci;

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+  JSAMPLE *range_limit = cinfo->sample_range_limit;

+  SHIFT_TEMPS

+

+  for (row = 0; row < num_rows; row++) {

+    /* Initialize output values to 0 so can process components separately */

+    jzero_far((void FAR *) output_buf[row],

+	      (size_t) (width * SIZEOF(JSAMPLE)));

+    for (ci = 0; ci < nc; ci++) {

+      input_ptr = input_buf[row] + ci;

+      output_ptr = output_buf[row];

+      if (cquantize->on_odd_row) {

+	/* work right to left in this row */

+	input_ptr += (width-1) * nc; /* so point to rightmost pixel */

+	output_ptr += width-1;

+	dir = -1;

+	dirnc = -nc;

+	errorptr = cquantize->fserrors[ci] + (width+1); /* => entry after last column */

+      } else {

+	/* work left to right in this row */

+	dir = 1;

+	dirnc = nc;

+	errorptr = cquantize->fserrors[ci]; /* => entry before first column */

+      }

+      colorindex_ci = cquantize->colorindex[ci];

+      colormap_ci = cquantize->sv_colormap[ci];

+      /* Preset error values: no error propagated to first pixel from left */

+      cur = 0;

+      /* and no error propagated to row below yet */

+      belowerr = bpreverr = 0;

+

+      for (col = width; col > 0; col--) {

+	/* cur holds the error propagated from the previous pixel on the

+	 * current line.  Add the error propagated from the previous line

+	 * to form the complete error correction term for this pixel, and

+	 * round the error term (which is expressed * 16) to an integer.

+	 * RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct

+	 * for either sign of the error value.

+	 * Note: errorptr points to *previous* column's array entry.

+	 */

+	cur = RIGHT_SHIFT(cur + errorptr[dir] + 8, 4);

+	/* Form pixel value + error, and range-limit to 0..MAXJSAMPLE.

+	 * The maximum error is +- MAXJSAMPLE; this sets the required size

+	 * of the range_limit array.

+	 */

+	cur += GETJSAMPLE(*input_ptr);

+	cur = GETJSAMPLE(range_limit[cur]);

+	/* Select output value, accumulate into output code for this pixel */

+	pixcode = GETJSAMPLE(colorindex_ci[cur]);

+	*output_ptr += (JSAMPLE) pixcode;

+	/* Compute actual representation error at this pixel */

+	/* Note: we can do this even though we don't have the final */

+	/* pixel code, because the colormap is orthogonal. */

+	cur -= GETJSAMPLE(colormap_ci[pixcode]);

+	/* Compute error fractions to be propagated to adjacent pixels.

+	 * Add these into the running sums, and simultaneously shift the

+	 * next-line error sums left by 1 column.

+	 */

+	bnexterr = cur;

+	delta = cur * 2;

+	cur += delta;		/* form error * 3 */

+	errorptr[0] = (FSERROR) (bpreverr + cur);

+	cur += delta;		/* form error * 5 */

+	bpreverr = belowerr + cur;

+	belowerr = bnexterr;

+	cur += delta;		/* form error * 7 */

+	/* At this point cur contains the 7/16 error value to be propagated

+	 * to the next pixel on the current line, and all the errors for the

+	 * next line have been shifted over. We are therefore ready to move on.

+	 */

+	input_ptr += dirnc;	/* advance input ptr to next column */

+	output_ptr += dir;	/* advance output ptr to next column */

+	errorptr += dir;	/* advance errorptr to current column */

+      }

+      /* Post-loop cleanup: we must unload the final error value into the

+       * final fserrors[] entry.  Note we need not unload belowerr because

+       * it is for the dummy column before or after the actual array.

+       */

+      errorptr[0] = (FSERROR) bpreverr; /* unload prev err into array */

+    }

+    cquantize->on_odd_row = (cquantize->on_odd_row ? FALSE : TRUE);

+  }

+}

+

+

+/*

+ * Allocate workspace for Floyd-Steinberg errors.

+ */

+

+LOCAL void

+alloc_fs_workspace (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  size_t arraysize;

+  int i;

+

+  arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR));

+  for (i = 0; i < cinfo->out_color_components; i++) {

+    cquantize->fserrors[i] = (FSERRPTR)

+      (*cinfo->mem->alloc_large)((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize);

+  }

+}

+

+

+/*

+ * Initialize for one-pass color quantization.

+ */

+

+METHODDEF void

+start_pass_1_quant (j_decompress_ptr cinfo, boolean is_pre_scan)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  size_t arraysize;

+  int i;

+

+  /* Install my colormap. */

+  cinfo->colormap = cquantize->sv_colormap;

+  cinfo->actual_number_of_colors = cquantize->sv_actual;

+

+  /* Initialize for desired dithering mode. */

+  switch (cinfo->dither_mode) {

+  case JDITHER_NONE:

+    if (cinfo->out_color_components == 3)

+      cquantize->pub.color_quantize = color_quantize3;

+    else

+      cquantize->pub.color_quantize = color_quantize;

+    break;

+  case JDITHER_ORDERED:

+    if (cinfo->out_color_components == 3)

+      cquantize->pub.color_quantize = quantize3_ord_dither;

+    else

+      cquantize->pub.color_quantize = quantize_ord_dither;

+    cquantize->row_index = 0;	/* initialize state for ordered dither */

+    /* If user changed to ordered dither from another mode,

+     * we must recreate the color index table with padding.

+     * This will cost extra space, but probably isn't very likely.

+     */

+    if (! cquantize->is_padded)

+      create_colorindex(cinfo);

+    /* Create ordered-dither tables if we didn't already. */

+    if (cquantize->odither[0] == NULL)

+      create_odither_tables(cinfo);

+    break;

+  case JDITHER_FS:

+    cquantize->pub.color_quantize = quantize_fs_dither;

+    cquantize->on_odd_row = FALSE; /* initialize state for F-S dither */

+    /* Allocate Floyd-Steinberg workspace if didn't already. */

+    if (cquantize->fserrors[0] == NULL)

+      alloc_fs_workspace(cinfo);

+    /* Initialize the propagated errors to zero. */

+    arraysize = (size_t) ((cinfo->output_width + 2) * SIZEOF(FSERROR));

+    for (i = 0; i < cinfo->out_color_components; i++)

+      jzero_far((void FAR *) cquantize->fserrors[i], arraysize);

+    break;

+  default:

+    ERREXIT(cinfo, JERR_NOT_COMPILED);

+    break;

+  }

+}

+

+

+/*

+ * Finish up at the end of the pass.

+ */

+

+METHODDEF void

+finish_pass_1_quant (j_decompress_ptr cinfo)

+{

+  /* no work in 1-pass case */

+}

+

+

+/*

+ * Switch to a new external colormap between output passes.

+ * Shouldn't get to this module!

+ */

+

+METHODDEF void

+new_color_map_1_quant (j_decompress_ptr cinfo)

+{

+  ERREXIT(cinfo, JERR_MODE_CHANGE);

+}

+

+

+/*

+ * Module initialization routine for 1-pass color quantization.

+ */

+

+GLOBAL void

+jinit_1pass_quantizer (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize;

+

+  cquantize = (my_cquantize_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_cquantizer));

+  cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize;

+  cquantize->pub.start_pass = start_pass_1_quant;

+  cquantize->pub.finish_pass = finish_pass_1_quant;

+  cquantize->pub.new_color_map = new_color_map_1_quant;

+  cquantize->fserrors[0] = NULL; /* Flag FS workspace not allocated */

+  cquantize->odither[0] = NULL;	/* Also flag odither arrays not allocated */

+

+  /* Make sure my internal arrays won't overflow */

+  if (cinfo->out_color_components > MAX_Q_COMPS)

+    ERREXIT1(cinfo, JERR_QUANT_COMPONENTS, MAX_Q_COMPS);

+  /* Make sure colormap indexes can be represented by JSAMPLEs */

+  if (cinfo->desired_number_of_colors > (MAXJSAMPLE+1))

+    ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXJSAMPLE+1);

+

+  /* Create the colormap and color index table. */

+  create_colormap(cinfo);

+  create_colorindex(cinfo);

+

+  /* Allocate Floyd-Steinberg workspace now if requested.

+   * We do this now since it is FAR storage and may affect the memory

+   * manager's space calculations.  If the user changes to FS dither

+   * mode in a later pass, we will allocate the space then, and will

+   * possibly overrun the max_memory_to_use setting.

+   */

+  if (cinfo->dither_mode == JDITHER_FS)

+    alloc_fs_workspace(cinfo);

+}

+

+#endif /* QUANT_1PASS_SUPPORTED */

diff --git a/code/jpeg-6/jquant2.c b/code/jpeg-6/jquant2.c
new file mode 100755
index 0000000..c944e4b
--- /dev/null
+++ b/code/jpeg-6/jquant2.c
@@ -0,0 +1,1310 @@
+/*

+ * jquant2.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains 2-pass color quantization (color mapping) routines.

+ * These routines provide selection of a custom color map for an image,

+ * followed by mapping of the image to that color map, with optional

+ * Floyd-Steinberg dithering.

+ * It is also possible to use just the second pass to map to an arbitrary

+ * externally-given color map.

+ *

+ * Note: ordered dithering is not supported, since there isn't any fast

+ * way to compute intercolor distances; it's unclear that ordered dither's

+ * fundamental assumptions even hold with an irregularly spaced color map.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+#ifdef QUANT_2PASS_SUPPORTED

+

+

+/*

+ * This module implements the well-known Heckbert paradigm for color

+ * quantization.  Most of the ideas used here can be traced back to

+ * Heckbert's seminal paper

+ *   Heckbert, Paul.  "Color Image Quantization for Frame Buffer Display",

+ *   Proc. SIGGRAPH '82, Computer Graphics v.16 #3 (July 1982), pp 297-304.

+ *

+ * In the first pass over the image, we accumulate a histogram showing the

+ * usage count of each possible color.  To keep the histogram to a reasonable

+ * size, we reduce the precision of the input; typical practice is to retain

+ * 5 or 6 bits per color, so that 8 or 4 different input values are counted

+ * in the same histogram cell.

+ *

+ * Next, the color-selection step begins with a box representing the whole

+ * color space, and repeatedly splits the "largest" remaining box until we

+ * have as many boxes as desired colors.  Then the mean color in each

+ * remaining box becomes one of the possible output colors.

+ * 

+ * The second pass over the image maps each input pixel to the closest output

+ * color (optionally after applying a Floyd-Steinberg dithering correction).

+ * This mapping is logically trivial, but making it go fast enough requires

+ * considerable care.

+ *

+ * Heckbert-style quantizers vary a good deal in their policies for choosing

+ * the "largest" box and deciding where to cut it.  The particular policies

+ * used here have proved out well in experimental comparisons, but better ones

+ * may yet be found.

+ *

+ * In earlier versions of the IJG code, this module quantized in YCbCr color

+ * space, processing the raw upsampled data without a color conversion step.

+ * This allowed the color conversion math to be done only once per colormap

+ * entry, not once per pixel.  However, that optimization precluded other

+ * useful optimizations (such as merging color conversion with upsampling)

+ * and it also interfered with desired capabilities such as quantizing to an

+ * externally-supplied colormap.  We have therefore abandoned that approach.

+ * The present code works in the post-conversion color space, typically RGB.

+ *

+ * To improve the visual quality of the results, we actually work in scaled

+ * RGB space, giving G distances more weight than R, and R in turn more than

+ * B.  To do everything in integer math, we must use integer scale factors.

+ * The 2/3/1 scale factors used here correspond loosely to the relative

+ * weights of the colors in the NTSC grayscale equation.

+ * If you want to use this code to quantize a non-RGB color space, you'll

+ * probably need to change these scale factors.

+ */

+

+#define R_SCALE 2		/* scale R distances by this much */

+#define G_SCALE 3		/* scale G distances by this much */

+#define B_SCALE 1		/* and B by this much */

+

+/* Relabel R/G/B as components 0/1/2, respecting the RGB ordering defined

+ * in jmorecfg.h.  As the code stands, it will do the right thing for R,G,B

+ * and B,G,R orders.  If you define some other weird order in jmorecfg.h,

+ * you'll get compile errors until you extend this logic.  In that case

+ * you'll probably want to tweak the histogram sizes too.

+ */

+

+#if RGB_RED == 0

+#define C0_SCALE R_SCALE

+#endif

+#if RGB_BLUE == 0

+#define C0_SCALE B_SCALE

+#endif

+#if RGB_GREEN == 1

+#define C1_SCALE G_SCALE

+#endif

+#if RGB_RED == 2

+#define C2_SCALE R_SCALE

+#endif

+#if RGB_BLUE == 2

+#define C2_SCALE B_SCALE

+#endif

+

+

+/*

+ * First we have the histogram data structure and routines for creating it.

+ *

+ * The number of bits of precision can be adjusted by changing these symbols.

+ * We recommend keeping 6 bits for G and 5 each for R and B.

+ * If you have plenty of memory and cycles, 6 bits all around gives marginally

+ * better results; if you are short of memory, 5 bits all around will save

+ * some space but degrade the results.

+ * To maintain a fully accurate histogram, we'd need to allocate a "long"

+ * (preferably unsigned long) for each cell.  In practice this is overkill;

+ * we can get by with 16 bits per cell.  Few of the cell counts will overflow,

+ * and clamping those that do overflow to the maximum value will give close-

+ * enough results.  This reduces the recommended histogram size from 256Kb

+ * to 128Kb, which is a useful savings on PC-class machines.

+ * (In the second pass the histogram space is re-used for pixel mapping data;

+ * in that capacity, each cell must be able to store zero to the number of

+ * desired colors.  16 bits/cell is plenty for that too.)

+ * Since the JPEG code is intended to run in small memory model on 80x86

+ * machines, we can't just allocate the histogram in one chunk.  Instead

+ * of a true 3-D array, we use a row of pointers to 2-D arrays.  Each

+ * pointer corresponds to a C0 value (typically 2^5 = 32 pointers) and

+ * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries.  Note that

+ * on 80x86 machines, the pointer row is in near memory but the actual

+ * arrays are in far memory (same arrangement as we use for image arrays).

+ */

+

+#define MAXNUMCOLORS  (MAXJSAMPLE+1) /* maximum size of colormap */

+

+/* These will do the right thing for either R,G,B or B,G,R color order,

+ * but you may not like the results for other color orders.

+ */

+#define HIST_C0_BITS  5		/* bits of precision in R/B histogram */

+#define HIST_C1_BITS  6		/* bits of precision in G histogram */

+#define HIST_C2_BITS  5		/* bits of precision in B/R histogram */

+

+/* Number of elements along histogram axes. */

+#define HIST_C0_ELEMS  (1<<HIST_C0_BITS)

+#define HIST_C1_ELEMS  (1<<HIST_C1_BITS)

+#define HIST_C2_ELEMS  (1<<HIST_C2_BITS)

+

+/* These are the amounts to shift an input value to get a histogram index. */

+#define C0_SHIFT  (BITS_IN_JSAMPLE-HIST_C0_BITS)

+#define C1_SHIFT  (BITS_IN_JSAMPLE-HIST_C1_BITS)

+#define C2_SHIFT  (BITS_IN_JSAMPLE-HIST_C2_BITS)

+

+

+typedef UINT16 histcell;	/* histogram cell; prefer an unsigned type */

+

+typedef histcell FAR * histptr;	/* for pointers to histogram cells */

+

+typedef histcell hist1d[HIST_C2_ELEMS]; /* typedefs for the array */

+typedef hist1d FAR * hist2d;	/* type for the 2nd-level pointers */

+typedef hist2d * hist3d;	/* type for top-level pointer */

+

+

+/* Declarations for Floyd-Steinberg dithering.

+ *

+ * Errors are accumulated into the array fserrors[], at a resolution of

+ * 1/16th of a pixel count.  The error at a given pixel is propagated

+ * to its not-yet-processed neighbors using the standard F-S fractions,

+ *		...	(here)	7/16

+ *		3/16	5/16	1/16

+ * We work left-to-right on even rows, right-to-left on odd rows.

+ *

+ * We can get away with a single array (holding one row's worth of errors)

+ * by using it to store the current row's errors at pixel columns not yet

+ * processed, but the next row's errors at columns already processed.  We

+ * need only a few extra variables to hold the errors immediately around the

+ * current column.  (If we are lucky, those variables are in registers, but

+ * even if not, they're probably cheaper to access than array elements are.)

+ *

+ * The fserrors[] array has (#columns + 2) entries; the extra entry at

+ * each end saves us from special-casing the first and last pixels.

+ * Each entry is three values long, one value for each color component.

+ *

+ * Note: on a wide image, we might not have enough room in a PC's near data

+ * segment to hold the error array; so it is allocated with alloc_large.

+ */

+

+#if BITS_IN_JSAMPLE == 8

+typedef INT16 FSERROR;		/* 16 bits should be enough */

+typedef int LOCFSERROR;		/* use 'int' for calculation temps */

+#else

+typedef INT32 FSERROR;		/* may need more than 16 bits */

+typedef INT32 LOCFSERROR;	/* be sure calculation temps are big enough */

+#endif

+

+typedef FSERROR FAR *FSERRPTR;	/* pointer to error array (in FAR storage!) */

+

+

+/* Private subobject */

+

+typedef struct {

+  struct jpeg_color_quantizer pub; /* public fields */

+

+  /* Space for the eventually created colormap is stashed here */

+  JSAMPARRAY sv_colormap;	/* colormap allocated at init time */

+  int desired;			/* desired # of colors = size of colormap */

+

+  /* Variables for accumulating image statistics */

+  hist3d histogram;		/* pointer to the histogram */

+

+  boolean needs_zeroed;		/* TRUE if next pass must zero histogram */

+

+  /* Variables for Floyd-Steinberg dithering */

+  FSERRPTR fserrors;		/* accumulated errors */

+  boolean on_odd_row;		/* flag to remember which row we are on */

+  int * error_limiter;		/* table for clamping the applied error */

+} my_cquantizer;

+

+typedef my_cquantizer * my_cquantize_ptr;

+

+

+/*

+ * Prescan some rows of pixels.

+ * In this module the prescan simply updates the histogram, which has been

+ * initialized to zeroes by start_pass.

+ * An output_buf parameter is required by the method signature, but no data

+ * is actually output (in fact the buffer controller is probably passing a

+ * NULL pointer).

+ */

+

+METHODDEF void

+prescan_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf,

+		  JSAMPARRAY output_buf, int num_rows)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  register JSAMPROW ptr;

+  register histptr histp;

+  register hist3d histogram = cquantize->histogram;

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+

+  for (row = 0; row < num_rows; row++) {

+    ptr = input_buf[row];

+    for (col = width; col > 0; col--) {

+      /* get pixel value and index into the histogram */

+      histp = & histogram[GETJSAMPLE(ptr[0]) >> C0_SHIFT]

+			 [GETJSAMPLE(ptr[1]) >> C1_SHIFT]

+			 [GETJSAMPLE(ptr[2]) >> C2_SHIFT];

+      /* increment, check for overflow and undo increment if so. */

+      if (++(*histp) <= 0)

+	(*histp)--;

+      ptr += 3;

+    }

+  }

+}

+

+

+/*

+ * Next we have the really interesting routines: selection of a colormap

+ * given the completed histogram.

+ * These routines work with a list of "boxes", each representing a rectangular

+ * subset of the input color space (to histogram precision).

+ */

+

+typedef struct {

+  /* The bounds of the box (inclusive); expressed as histogram indexes */

+  int c0min, c0max;

+  int c1min, c1max;

+  int c2min, c2max;

+  /* The volume (actually 2-norm) of the box */

+  INT32 volume;

+  /* The number of nonzero histogram cells within this box */

+  long colorcount;

+} box;

+

+typedef box * boxptr;

+

+

+LOCAL boxptr

+find_biggest_color_pop (boxptr boxlist, int numboxes)

+/* Find the splittable box with the largest color population */

+/* Returns NULL if no splittable boxes remain */

+{

+  register boxptr boxp;

+  register int i;

+  register long maxc = 0;

+  boxptr which = NULL;

+  

+  for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {

+    if (boxp->colorcount > maxc && boxp->volume > 0) {

+      which = boxp;

+      maxc = boxp->colorcount;

+    }

+  }

+  return which;

+}

+

+

+LOCAL boxptr

+find_biggest_volume (boxptr boxlist, int numboxes)

+/* Find the splittable box with the largest (scaled) volume */

+/* Returns NULL if no splittable boxes remain */

+{

+  register boxptr boxp;

+  register int i;

+  register INT32 maxv = 0;

+  boxptr which = NULL;

+  

+  for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {

+    if (boxp->volume > maxv) {

+      which = boxp;

+      maxv = boxp->volume;

+    }

+  }

+  return which;

+}

+

+

+LOCAL void

+update_box (j_decompress_ptr cinfo, boxptr boxp)

+/* Shrink the min/max bounds of a box to enclose only nonzero elements, */

+/* and recompute its volume and population */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  histptr histp;

+  int c0,c1,c2;

+  int c0min,c0max,c1min,c1max,c2min,c2max;

+  INT32 dist0,dist1,dist2;

+  long ccount;

+  

+  c0min = boxp->c0min;  c0max = boxp->c0max;

+  c1min = boxp->c1min;  c1max = boxp->c1max;

+  c2min = boxp->c2min;  c2max = boxp->c2max;

+  

+  if (c0max > c0min)

+    for (c0 = c0min; c0 <= c0max; c0++)

+      for (c1 = c1min; c1 <= c1max; c1++) {

+	histp = & histogram[c0][c1][c2min];

+	for (c2 = c2min; c2 <= c2max; c2++)

+	  if (*histp++ != 0) {

+	    boxp->c0min = c0min = c0;

+	    goto have_c0min;

+	  }

+      }

+ have_c0min:

+  if (c0max > c0min)

+    for (c0 = c0max; c0 >= c0min; c0--)

+      for (c1 = c1min; c1 <= c1max; c1++) {

+	histp = & histogram[c0][c1][c2min];

+	for (c2 = c2min; c2 <= c2max; c2++)

+	  if (*histp++ != 0) {

+	    boxp->c0max = c0max = c0;

+	    goto have_c0max;

+	  }

+      }

+ have_c0max:

+  if (c1max > c1min)

+    for (c1 = c1min; c1 <= c1max; c1++)

+      for (c0 = c0min; c0 <= c0max; c0++) {

+	histp = & histogram[c0][c1][c2min];

+	for (c2 = c2min; c2 <= c2max; c2++)

+	  if (*histp++ != 0) {

+	    boxp->c1min = c1min = c1;

+	    goto have_c1min;

+	  }

+      }

+ have_c1min:

+  if (c1max > c1min)

+    for (c1 = c1max; c1 >= c1min; c1--)

+      for (c0 = c0min; c0 <= c0max; c0++) {

+	histp = & histogram[c0][c1][c2min];

+	for (c2 = c2min; c2 <= c2max; c2++)

+	  if (*histp++ != 0) {

+	    boxp->c1max = c1max = c1;

+	    goto have_c1max;

+	  }

+      }

+ have_c1max:

+  if (c2max > c2min)

+    for (c2 = c2min; c2 <= c2max; c2++)

+      for (c0 = c0min; c0 <= c0max; c0++) {

+	histp = & histogram[c0][c1min][c2];

+	for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)

+	  if (*histp != 0) {

+	    boxp->c2min = c2min = c2;

+	    goto have_c2min;

+	  }

+      }

+ have_c2min:

+  if (c2max > c2min)

+    for (c2 = c2max; c2 >= c2min; c2--)

+      for (c0 = c0min; c0 <= c0max; c0++) {

+	histp = & histogram[c0][c1min][c2];

+	for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)

+	  if (*histp != 0) {

+	    boxp->c2max = c2max = c2;

+	    goto have_c2max;

+	  }

+      }

+ have_c2max:

+

+  /* Update box volume.

+   * We use 2-norm rather than real volume here; this biases the method

+   * against making long narrow boxes, and it has the side benefit that

+   * a box is splittable iff norm > 0.

+   * Since the differences are expressed in histogram-cell units,

+   * we have to shift back to JSAMPLE units to get consistent distances;

+   * after which, we scale according to the selected distance scale factors.

+   */

+  dist0 = ((c0max - c0min) << C0_SHIFT) * C0_SCALE;

+  dist1 = ((c1max - c1min) << C1_SHIFT) * C1_SCALE;

+  dist2 = ((c2max - c2min) << C2_SHIFT) * C2_SCALE;

+  boxp->volume = dist0*dist0 + dist1*dist1 + dist2*dist2;

+  

+  /* Now scan remaining volume of box and compute population */

+  ccount = 0;

+  for (c0 = c0min; c0 <= c0max; c0++)

+    for (c1 = c1min; c1 <= c1max; c1++) {

+      histp = & histogram[c0][c1][c2min];

+      for (c2 = c2min; c2 <= c2max; c2++, histp++)

+	if (*histp != 0) {

+	  ccount++;

+	}

+    }

+  boxp->colorcount = ccount;

+}

+

+

+LOCAL int

+median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes,

+	    int desired_colors)

+/* Repeatedly select and split the largest box until we have enough boxes */

+{

+  int n,lb;

+  int c0,c1,c2,cmax;

+  register boxptr b1,b2;

+

+  while (numboxes < desired_colors) {

+    /* Select box to split.

+     * Current algorithm: by population for first half, then by volume.

+     */

+    if (numboxes*2 <= desired_colors) {

+      b1 = find_biggest_color_pop(boxlist, numboxes);

+    } else {

+      b1 = find_biggest_volume(boxlist, numboxes);

+    }

+    if (b1 == NULL)		/* no splittable boxes left! */

+      break;

+    b2 = &boxlist[numboxes];	/* where new box will go */

+    /* Copy the color bounds to the new box. */

+    b2->c0max = b1->c0max; b2->c1max = b1->c1max; b2->c2max = b1->c2max;

+    b2->c0min = b1->c0min; b2->c1min = b1->c1min; b2->c2min = b1->c2min;

+    /* Choose which axis to split the box on.

+     * Current algorithm: longest scaled axis.

+     * See notes in update_box about scaling distances.

+     */

+    c0 = ((b1->c0max - b1->c0min) << C0_SHIFT) * C0_SCALE;

+    c1 = ((b1->c1max - b1->c1min) << C1_SHIFT) * C1_SCALE;

+    c2 = ((b1->c2max - b1->c2min) << C2_SHIFT) * C2_SCALE;

+    /* We want to break any ties in favor of green, then red, blue last.

+     * This code does the right thing for R,G,B or B,G,R color orders only.

+     */

+#if RGB_RED == 0

+    cmax = c1; n = 1;

+    if (c0 > cmax) { cmax = c0; n = 0; }

+    if (c2 > cmax) { n = 2; }

+#else

+    cmax = c1; n = 1;

+    if (c2 > cmax) { cmax = c2; n = 2; }

+    if (c0 > cmax) { n = 0; }

+#endif

+    /* Choose split point along selected axis, and update box bounds.

+     * Current algorithm: split at halfway point.

+     * (Since the box has been shrunk to minimum volume,

+     * any split will produce two nonempty subboxes.)

+     * Note that lb value is max for lower box, so must be < old max.

+     */

+    switch (n) {

+    case 0:

+      lb = (b1->c0max + b1->c0min) / 2;

+      b1->c0max = lb;

+      b2->c0min = lb+1;

+      break;

+    case 1:

+      lb = (b1->c1max + b1->c1min) / 2;

+      b1->c1max = lb;

+      b2->c1min = lb+1;

+      break;

+    case 2:

+      lb = (b1->c2max + b1->c2min) / 2;

+      b1->c2max = lb;

+      b2->c2min = lb+1;

+      break;

+    }

+    /* Update stats for boxes */

+    update_box(cinfo, b1);

+    update_box(cinfo, b2);

+    numboxes++;

+  }

+  return numboxes;

+}

+

+

+LOCAL void

+compute_color (j_decompress_ptr cinfo, boxptr boxp, int icolor)

+/* Compute representative color for a box, put it in colormap[icolor] */

+{

+  /* Current algorithm: mean weighted by pixels (not colors) */

+  /* Note it is important to get the rounding correct! */

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  histptr histp;

+  int c0,c1,c2;

+  int c0min,c0max,c1min,c1max,c2min,c2max;

+  long count;

+  long total = 0;

+  long c0total = 0;

+  long c1total = 0;

+  long c2total = 0;

+  

+  c0min = boxp->c0min;  c0max = boxp->c0max;

+  c1min = boxp->c1min;  c1max = boxp->c1max;

+  c2min = boxp->c2min;  c2max = boxp->c2max;

+  

+  for (c0 = c0min; c0 <= c0max; c0++)

+    for (c1 = c1min; c1 <= c1max; c1++) {

+      histp = & histogram[c0][c1][c2min];

+      for (c2 = c2min; c2 <= c2max; c2++) {

+	if ((count = *histp++) != 0) {

+	  total += count;

+	  c0total += ((c0 << C0_SHIFT) + ((1<<C0_SHIFT)>>1)) * count;

+	  c1total += ((c1 << C1_SHIFT) + ((1<<C1_SHIFT)>>1)) * count;

+	  c2total += ((c2 << C2_SHIFT) + ((1<<C2_SHIFT)>>1)) * count;

+	}

+      }

+    }

+  

+  cinfo->colormap[0][icolor] = (JSAMPLE) ((c0total + (total>>1)) / total);

+  cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total>>1)) / total);

+  cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total>>1)) / total);

+}

+

+

+LOCAL void

+select_colors (j_decompress_ptr cinfo, int desired_colors)

+/* Master routine for color selection */

+{

+  boxptr boxlist;

+  int numboxes;

+  int i;

+

+  /* Allocate workspace for box list */

+  boxlist = (boxptr) (*cinfo->mem->alloc_small)

+    ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * SIZEOF(box));

+  /* Initialize one box containing whole space */

+  numboxes = 1;

+  boxlist[0].c0min = 0;

+  boxlist[0].c0max = MAXJSAMPLE >> C0_SHIFT;

+  boxlist[0].c1min = 0;

+  boxlist[0].c1max = MAXJSAMPLE >> C1_SHIFT;

+  boxlist[0].c2min = 0;

+  boxlist[0].c2max = MAXJSAMPLE >> C2_SHIFT;

+  /* Shrink it to actually-used volume and set its statistics */

+  update_box(cinfo, & boxlist[0]);

+  /* Perform median-cut to produce final box list */

+  numboxes = median_cut(cinfo, boxlist, numboxes, desired_colors);

+  /* Compute the representative color for each box, fill colormap */

+  for (i = 0; i < numboxes; i++)

+    compute_color(cinfo, & boxlist[i], i);

+  cinfo->actual_number_of_colors = numboxes;

+  TRACEMS1(cinfo, 1, JTRC_QUANT_SELECTED, numboxes);

+}

+

+

+/*

+ * These routines are concerned with the time-critical task of mapping input

+ * colors to the nearest color in the selected colormap.

+ *

+ * We re-use the histogram space as an "inverse color map", essentially a

+ * cache for the results of nearest-color searches.  All colors within a

+ * histogram cell will be mapped to the same colormap entry, namely the one

+ * closest to the cell's center.  This may not be quite the closest entry to

+ * the actual input color, but it's almost as good.  A zero in the cache

+ * indicates we haven't found the nearest color for that cell yet; the array

+ * is cleared to zeroes before starting the mapping pass.  When we find the

+ * nearest color for a cell, its colormap index plus one is recorded in the

+ * cache for future use.  The pass2 scanning routines call fill_inverse_cmap

+ * when they need to use an unfilled entry in the cache.

+ *

+ * Our method of efficiently finding nearest colors is based on the "locally

+ * sorted search" idea described by Heckbert and on the incremental distance

+ * calculation described by Spencer W. Thomas in chapter III.1 of Graphics

+ * Gems II (James Arvo, ed.  Academic Press, 1991).  Thomas points out that

+ * the distances from a given colormap entry to each cell of the histogram can

+ * be computed quickly using an incremental method: the differences between

+ * distances to adjacent cells themselves differ by a constant.  This allows a

+ * fairly fast implementation of the "brute force" approach of computing the

+ * distance from every colormap entry to every histogram cell.  Unfortunately,

+ * it needs a work array to hold the best-distance-so-far for each histogram

+ * cell (because the inner loop has to be over cells, not colormap entries).

+ * The work array elements have to be INT32s, so the work array would need

+ * 256Kb at our recommended precision.  This is not feasible in DOS machines.

+ *

+ * To get around these problems, we apply Thomas' method to compute the

+ * nearest colors for only the cells within a small subbox of the histogram.

+ * The work array need be only as big as the subbox, so the memory usage

+ * problem is solved.  Furthermore, we need not fill subboxes that are never

+ * referenced in pass2; many images use only part of the color gamut, so a

+ * fair amount of work is saved.  An additional advantage of this

+ * approach is that we can apply Heckbert's locality criterion to quickly

+ * eliminate colormap entries that are far away from the subbox; typically

+ * three-fourths of the colormap entries are rejected by Heckbert's criterion,

+ * and we need not compute their distances to individual cells in the subbox.

+ * The speed of this approach is heavily influenced by the subbox size: too

+ * small means too much overhead, too big loses because Heckbert's criterion

+ * can't eliminate as many colormap entries.  Empirically the best subbox

+ * size seems to be about 1/512th of the histogram (1/8th in each direction).

+ *

+ * Thomas' article also describes a refined method which is asymptotically

+ * faster than the brute-force method, but it is also far more complex and

+ * cannot efficiently be applied to small subboxes.  It is therefore not

+ * useful for programs intended to be portable to DOS machines.  On machines

+ * with plenty of memory, filling the whole histogram in one shot with Thomas'

+ * refined method might be faster than the present code --- but then again,

+ * it might not be any faster, and it's certainly more complicated.

+ */

+

+

+/* log2(histogram cells in update box) for each axis; this can be adjusted */

+#define BOX_C0_LOG  (HIST_C0_BITS-3)

+#define BOX_C1_LOG  (HIST_C1_BITS-3)

+#define BOX_C2_LOG  (HIST_C2_BITS-3)

+

+#define BOX_C0_ELEMS  (1<<BOX_C0_LOG) /* # of hist cells in update box */

+#define BOX_C1_ELEMS  (1<<BOX_C1_LOG)

+#define BOX_C2_ELEMS  (1<<BOX_C2_LOG)

+

+#define BOX_C0_SHIFT  (C0_SHIFT + BOX_C0_LOG)

+#define BOX_C1_SHIFT  (C1_SHIFT + BOX_C1_LOG)

+#define BOX_C2_SHIFT  (C2_SHIFT + BOX_C2_LOG)

+

+

+/*

+ * The next three routines implement inverse colormap filling.  They could

+ * all be folded into one big routine, but splitting them up this way saves

+ * some stack space (the mindist[] and bestdist[] arrays need not coexist)

+ * and may allow some compilers to produce better code by registerizing more

+ * inner-loop variables.

+ */

+

+LOCAL int

+find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,

+		    JSAMPLE colorlist[])

+/* Locate the colormap entries close enough to an update box to be candidates

+ * for the nearest entry to some cell(s) in the update box.  The update box

+ * is specified by the center coordinates of its first cell.  The number of

+ * candidate colormap entries is returned, and their colormap indexes are

+ * placed in colorlist[].

+ * This routine uses Heckbert's "locally sorted search" criterion to select

+ * the colors that need further consideration.

+ */

+{

+  int numcolors = cinfo->actual_number_of_colors;

+  int maxc0, maxc1, maxc2;

+  int centerc0, centerc1, centerc2;

+  int i, x, ncolors;

+  INT32 minmaxdist, min_dist, max_dist, tdist;

+  INT32 mindist[MAXNUMCOLORS];	/* min distance to colormap entry i */

+

+  /* Compute true coordinates of update box's upper corner and center.

+   * Actually we compute the coordinates of the center of the upper-corner

+   * histogram cell, which are the upper bounds of the volume we care about.

+   * Note that since ">>" rounds down, the "center" values may be closer to

+   * min than to max; hence comparisons to them must be "<=", not "<".

+   */

+  maxc0 = minc0 + ((1 << BOX_C0_SHIFT) - (1 << C0_SHIFT));

+  centerc0 = (minc0 + maxc0) >> 1;

+  maxc1 = minc1 + ((1 << BOX_C1_SHIFT) - (1 << C1_SHIFT));

+  centerc1 = (minc1 + maxc1) >> 1;

+  maxc2 = minc2 + ((1 << BOX_C2_SHIFT) - (1 << C2_SHIFT));

+  centerc2 = (minc2 + maxc2) >> 1;

+

+  /* For each color in colormap, find:

+   *  1. its minimum squared-distance to any point in the update box

+   *     (zero if color is within update box);

+   *  2. its maximum squared-distance to any point in the update box.

+   * Both of these can be found by considering only the corners of the box.

+   * We save the minimum distance for each color in mindist[];

+   * only the smallest maximum distance is of interest.

+   */

+  minmaxdist = 0x7FFFFFFFL;

+

+  for (i = 0; i < numcolors; i++) {

+    /* We compute the squared-c0-distance term, then add in the other two. */

+    x = GETJSAMPLE(cinfo->colormap[0][i]);

+    if (x < minc0) {

+      tdist = (x - minc0) * C0_SCALE;

+      min_dist = tdist*tdist;

+      tdist = (x - maxc0) * C0_SCALE;

+      max_dist = tdist*tdist;

+    } else if (x > maxc0) {

+      tdist = (x - maxc0) * C0_SCALE;

+      min_dist = tdist*tdist;

+      tdist = (x - minc0) * C0_SCALE;

+      max_dist = tdist*tdist;

+    } else {

+      /* within cell range so no contribution to min_dist */

+      min_dist = 0;

+      if (x <= centerc0) {

+	tdist = (x - maxc0) * C0_SCALE;

+	max_dist = tdist*tdist;

+      } else {

+	tdist = (x - minc0) * C0_SCALE;

+	max_dist = tdist*tdist;

+      }

+    }

+

+    x = GETJSAMPLE(cinfo->colormap[1][i]);

+    if (x < minc1) {

+      tdist = (x - minc1) * C1_SCALE;

+      min_dist += tdist*tdist;

+      tdist = (x - maxc1) * C1_SCALE;

+      max_dist += tdist*tdist;

+    } else if (x > maxc1) {

+      tdist = (x - maxc1) * C1_SCALE;

+      min_dist += tdist*tdist;

+      tdist = (x - minc1) * C1_SCALE;

+      max_dist += tdist*tdist;

+    } else {

+      /* within cell range so no contribution to min_dist */

+      if (x <= centerc1) {

+	tdist = (x - maxc1) * C1_SCALE;

+	max_dist += tdist*tdist;

+      } else {

+	tdist = (x - minc1) * C1_SCALE;

+	max_dist += tdist*tdist;

+      }

+    }

+

+    x = GETJSAMPLE(cinfo->colormap[2][i]);

+    if (x < minc2) {

+      tdist = (x - minc2) * C2_SCALE;

+      min_dist += tdist*tdist;

+      tdist = (x - maxc2) * C2_SCALE;

+      max_dist += tdist*tdist;

+    } else if (x > maxc2) {

+      tdist = (x - maxc2) * C2_SCALE;

+      min_dist += tdist*tdist;

+      tdist = (x - minc2) * C2_SCALE;

+      max_dist += tdist*tdist;

+    } else {

+      /* within cell range so no contribution to min_dist */

+      if (x <= centerc2) {

+	tdist = (x - maxc2) * C2_SCALE;

+	max_dist += tdist*tdist;

+      } else {

+	tdist = (x - minc2) * C2_SCALE;

+	max_dist += tdist*tdist;

+      }

+    }

+

+    mindist[i] = min_dist;	/* save away the results */

+    if (max_dist < minmaxdist)

+      minmaxdist = max_dist;

+  }

+

+  /* Now we know that no cell in the update box is more than minmaxdist

+   * away from some colormap entry.  Therefore, only colors that are

+   * within minmaxdist of some part of the box need be considered.

+   */

+  ncolors = 0;

+  for (i = 0; i < numcolors; i++) {

+    if (mindist[i] <= minmaxdist)

+      colorlist[ncolors++] = (JSAMPLE) i;

+  }

+  return ncolors;

+}

+

+

+LOCAL void

+find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,

+		  int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[])

+/* Find the closest colormap entry for each cell in the update box,

+ * given the list of candidate colors prepared by find_nearby_colors.

+ * Return the indexes of the closest entries in the bestcolor[] array.

+ * This routine uses Thomas' incremental distance calculation method to

+ * find the distance from a colormap entry to successive cells in the box.

+ */

+{

+  int ic0, ic1, ic2;

+  int i, icolor;

+  register INT32 * bptr;	/* pointer into bestdist[] array */

+  JSAMPLE * cptr;		/* pointer into bestcolor[] array */

+  INT32 dist0, dist1;		/* initial distance values */

+  register INT32 dist2;		/* current distance in inner loop */

+  INT32 xx0, xx1;		/* distance increments */

+  register INT32 xx2;

+  INT32 inc0, inc1, inc2;	/* initial values for increments */

+  /* This array holds the distance to the nearest-so-far color for each cell */

+  INT32 bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];

+

+  /* Initialize best-distance for each cell of the update box */

+  bptr = bestdist;

+  for (i = BOX_C0_ELEMS*BOX_C1_ELEMS*BOX_C2_ELEMS-1; i >= 0; i--)

+    *bptr++ = 0x7FFFFFFFL;

+  

+  /* For each color selected by find_nearby_colors,

+   * compute its distance to the center of each cell in the box.

+   * If that's less than best-so-far, update best distance and color number.

+   */

+  

+  /* Nominal steps between cell centers ("x" in Thomas article) */

+#define STEP_C0  ((1 << C0_SHIFT) * C0_SCALE)

+#define STEP_C1  ((1 << C1_SHIFT) * C1_SCALE)

+#define STEP_C2  ((1 << C2_SHIFT) * C2_SCALE)

+  

+  for (i = 0; i < numcolors; i++) {

+    icolor = GETJSAMPLE(colorlist[i]);

+    /* Compute (square of) distance from minc0/c1/c2 to this color */

+    inc0 = (minc0 - GETJSAMPLE(cinfo->colormap[0][icolor])) * C0_SCALE;

+    dist0 = inc0*inc0;

+    inc1 = (minc1 - GETJSAMPLE(cinfo->colormap[1][icolor])) * C1_SCALE;

+    dist0 += inc1*inc1;

+    inc2 = (minc2 - GETJSAMPLE(cinfo->colormap[2][icolor])) * C2_SCALE;

+    dist0 += inc2*inc2;

+    /* Form the initial difference increments */

+    inc0 = inc0 * (2 * STEP_C0) + STEP_C0 * STEP_C0;

+    inc1 = inc1 * (2 * STEP_C1) + STEP_C1 * STEP_C1;

+    inc2 = inc2 * (2 * STEP_C2) + STEP_C2 * STEP_C2;

+    /* Now loop over all cells in box, updating distance per Thomas method */

+    bptr = bestdist;

+    cptr = bestcolor;

+    xx0 = inc0;

+    for (ic0 = BOX_C0_ELEMS-1; ic0 >= 0; ic0--) {

+      dist1 = dist0;

+      xx1 = inc1;

+      for (ic1 = BOX_C1_ELEMS-1; ic1 >= 0; ic1--) {

+	dist2 = dist1;

+	xx2 = inc2;

+	for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) {

+	  if (dist2 < *bptr) {

+	    *bptr = dist2;

+	    *cptr = (JSAMPLE) icolor;

+	  }

+	  dist2 += xx2;

+	  xx2 += 2 * STEP_C2 * STEP_C2;

+	  bptr++;

+	  cptr++;

+	}

+	dist1 += xx1;

+	xx1 += 2 * STEP_C1 * STEP_C1;

+      }

+      dist0 += xx0;

+      xx0 += 2 * STEP_C0 * STEP_C0;

+    }

+  }

+}

+

+

+LOCAL void

+fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)

+/* Fill the inverse-colormap entries in the update box that contains */

+/* histogram cell c0/c1/c2.  (Only that one cell MUST be filled, but */

+/* we can fill as many others as we wish.) */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  int minc0, minc1, minc2;	/* lower left corner of update box */

+  int ic0, ic1, ic2;

+  register JSAMPLE * cptr;	/* pointer into bestcolor[] array */

+  register histptr cachep;	/* pointer into main cache array */

+  /* This array lists the candidate colormap indexes. */

+  JSAMPLE colorlist[MAXNUMCOLORS];

+  int numcolors;		/* number of candidate colors */

+  /* This array holds the actually closest colormap index for each cell. */

+  JSAMPLE bestcolor[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];

+

+  /* Convert cell coordinates to update box ID */

+  c0 >>= BOX_C0_LOG;

+  c1 >>= BOX_C1_LOG;

+  c2 >>= BOX_C2_LOG;

+

+  /* Compute true coordinates of update box's origin corner.

+   * Actually we compute the coordinates of the center of the corner

+   * histogram cell, which are the lower bounds of the volume we care about.

+   */

+  minc0 = (c0 << BOX_C0_SHIFT) + ((1 << C0_SHIFT) >> 1);

+  minc1 = (c1 << BOX_C1_SHIFT) + ((1 << C1_SHIFT) >> 1);

+  minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1);

+  

+  /* Determine which colormap entries are close enough to be candidates

+   * for the nearest entry to some cell in the update box.

+   */

+  numcolors = find_nearby_colors(cinfo, minc0, minc1, minc2, colorlist);

+

+  /* Determine the actually nearest colors. */

+  find_best_colors(cinfo, minc0, minc1, minc2, numcolors, colorlist,

+		   bestcolor);

+

+  /* Save the best color numbers (plus 1) in the main cache array */

+  c0 <<= BOX_C0_LOG;		/* convert ID back to base cell indexes */

+  c1 <<= BOX_C1_LOG;

+  c2 <<= BOX_C2_LOG;

+  cptr = bestcolor;

+  for (ic0 = 0; ic0 < BOX_C0_ELEMS; ic0++) {

+    for (ic1 = 0; ic1 < BOX_C1_ELEMS; ic1++) {

+      cachep = & histogram[c0+ic0][c1+ic1][c2];

+      for (ic2 = 0; ic2 < BOX_C2_ELEMS; ic2++) {

+	*cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1);

+      }

+    }

+  }

+}

+

+

+/*

+ * Map some rows of pixels to the output colormapped representation.

+ */

+

+METHODDEF void

+pass2_no_dither (j_decompress_ptr cinfo,

+		 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)

+/* This version performs no dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  register JSAMPROW inptr, outptr;

+  register histptr cachep;

+  register int c0, c1, c2;

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+

+  for (row = 0; row < num_rows; row++) {

+    inptr = input_buf[row];

+    outptr = output_buf[row];

+    for (col = width; col > 0; col--) {

+      /* get pixel value and index into the cache */

+      c0 = GETJSAMPLE(*inptr++) >> C0_SHIFT;

+      c1 = GETJSAMPLE(*inptr++) >> C1_SHIFT;

+      c2 = GETJSAMPLE(*inptr++) >> C2_SHIFT;

+      cachep = & histogram[c0][c1][c2];

+      /* If we have not seen this color before, find nearest colormap entry */

+      /* and update the cache */

+      if (*cachep == 0)

+	fill_inverse_cmap(cinfo, c0,c1,c2);

+      /* Now emit the colormap index for this cell */

+      *outptr++ = (JSAMPLE) (*cachep - 1);

+    }

+  }

+}

+

+

+METHODDEF void

+pass2_fs_dither (j_decompress_ptr cinfo,

+		 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)

+/* This version performs Floyd-Steinberg dithering */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  register LOCFSERROR cur0, cur1, cur2;	/* current error or pixel value */

+  LOCFSERROR belowerr0, belowerr1, belowerr2; /* error for pixel below cur */

+  LOCFSERROR bpreverr0, bpreverr1, bpreverr2; /* error for below/prev col */

+  register FSERRPTR errorptr;	/* => fserrors[] at column before current */

+  JSAMPROW inptr;		/* => current input pixel */

+  JSAMPROW outptr;		/* => current output pixel */

+  histptr cachep;

+  int dir;			/* +1 or -1 depending on direction */

+  int dir3;			/* 3*dir, for advancing inptr & errorptr */

+  int row;

+  JDIMENSION col;

+  JDIMENSION width = cinfo->output_width;

+  JSAMPLE *range_limit = cinfo->sample_range_limit;

+  int *error_limit = cquantize->error_limiter;

+  JSAMPROW colormap0 = cinfo->colormap[0];

+  JSAMPROW colormap1 = cinfo->colormap[1];

+  JSAMPROW colormap2 = cinfo->colormap[2];

+  SHIFT_TEMPS

+

+  for (row = 0; row < num_rows; row++) {

+    inptr = input_buf[row];

+    outptr = output_buf[row];

+    if (cquantize->on_odd_row) {

+      /* work right to left in this row */

+      inptr += (width-1) * 3;	/* so point to rightmost pixel */

+      outptr += width-1;

+      dir = -1;

+      dir3 = -3;

+      errorptr = cquantize->fserrors + (width+1)*3; /* => entry after last column */

+      cquantize->on_odd_row = FALSE; /* flip for next time */

+    } else {

+      /* work left to right in this row */

+      dir = 1;

+      dir3 = 3;

+      errorptr = cquantize->fserrors; /* => entry before first real column */

+      cquantize->on_odd_row = TRUE; /* flip for next time */

+    }

+    /* Preset error values: no error propagated to first pixel from left */

+    cur0 = cur1 = cur2 = 0;

+    /* and no error propagated to row below yet */

+    belowerr0 = belowerr1 = belowerr2 = 0;

+    bpreverr0 = bpreverr1 = bpreverr2 = 0;

+

+    for (col = width; col > 0; col--) {

+      /* curN holds the error propagated from the previous pixel on the

+       * current line.  Add the error propagated from the previous line

+       * to form the complete error correction term for this pixel, and

+       * round the error term (which is expressed * 16) to an integer.

+       * RIGHT_SHIFT rounds towards minus infinity, so adding 8 is correct

+       * for either sign of the error value.

+       * Note: errorptr points to *previous* column's array entry.

+       */

+      cur0 = RIGHT_SHIFT(cur0 + errorptr[dir3+0] + 8, 4);

+      cur1 = RIGHT_SHIFT(cur1 + errorptr[dir3+1] + 8, 4);

+      cur2 = RIGHT_SHIFT(cur2 + errorptr[dir3+2] + 8, 4);

+      /* Limit the error using transfer function set by init_error_limit.

+       * See comments with init_error_limit for rationale.

+       */

+      cur0 = error_limit[cur0];

+      cur1 = error_limit[cur1];

+      cur2 = error_limit[cur2];

+      /* Form pixel value + error, and range-limit to 0..MAXJSAMPLE.

+       * The maximum error is +- MAXJSAMPLE (or less with error limiting);

+       * this sets the required size of the range_limit array.

+       */

+      cur0 += GETJSAMPLE(inptr[0]);

+      cur1 += GETJSAMPLE(inptr[1]);

+      cur2 += GETJSAMPLE(inptr[2]);

+      cur0 = GETJSAMPLE(range_limit[cur0]);

+      cur1 = GETJSAMPLE(range_limit[cur1]);

+      cur2 = GETJSAMPLE(range_limit[cur2]);

+      /* Index into the cache with adjusted pixel value */

+      cachep = & histogram[cur0>>C0_SHIFT][cur1>>C1_SHIFT][cur2>>C2_SHIFT];

+      /* If we have not seen this color before, find nearest colormap */

+      /* entry and update the cache */

+      if (*cachep == 0)

+	fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT);

+      /* Now emit the colormap index for this cell */

+      { register int pixcode = *cachep - 1;

+	*outptr = (JSAMPLE) pixcode;

+	/* Compute representation error for this pixel */

+	cur0 -= GETJSAMPLE(colormap0[pixcode]);

+	cur1 -= GETJSAMPLE(colormap1[pixcode]);

+	cur2 -= GETJSAMPLE(colormap2[pixcode]);

+      }

+      /* Compute error fractions to be propagated to adjacent pixels.

+       * Add these into the running sums, and simultaneously shift the

+       * next-line error sums left by 1 column.

+       */

+      { register LOCFSERROR bnexterr, delta;

+

+	bnexterr = cur0;	/* Process component 0 */

+	delta = cur0 * 2;

+	cur0 += delta;		/* form error * 3 */

+	errorptr[0] = (FSERROR) (bpreverr0 + cur0);

+	cur0 += delta;		/* form error * 5 */

+	bpreverr0 = belowerr0 + cur0;

+	belowerr0 = bnexterr;

+	cur0 += delta;		/* form error * 7 */

+	bnexterr = cur1;	/* Process component 1 */

+	delta = cur1 * 2;

+	cur1 += delta;		/* form error * 3 */

+	errorptr[1] = (FSERROR) (bpreverr1 + cur1);

+	cur1 += delta;		/* form error * 5 */

+	bpreverr1 = belowerr1 + cur1;

+	belowerr1 = bnexterr;

+	cur1 += delta;		/* form error * 7 */

+	bnexterr = cur2;	/* Process component 2 */

+	delta = cur2 * 2;

+	cur2 += delta;		/* form error * 3 */

+	errorptr[2] = (FSERROR) (bpreverr2 + cur2);

+	cur2 += delta;		/* form error * 5 */

+	bpreverr2 = belowerr2 + cur2;

+	belowerr2 = bnexterr;

+	cur2 += delta;		/* form error * 7 */

+      }

+      /* At this point curN contains the 7/16 error value to be propagated

+       * to the next pixel on the current line, and all the errors for the

+       * next line have been shifted over.  We are therefore ready to move on.

+       */

+      inptr += dir3;		/* Advance pixel pointers to next column */

+      outptr += dir;

+      errorptr += dir3;		/* advance errorptr to current column */

+    }

+    /* Post-loop cleanup: we must unload the final error values into the

+     * final fserrors[] entry.  Note we need not unload belowerrN because

+     * it is for the dummy column before or after the actual array.

+     */

+    errorptr[0] = (FSERROR) bpreverr0; /* unload prev errs into array */

+    errorptr[1] = (FSERROR) bpreverr1;

+    errorptr[2] = (FSERROR) bpreverr2;

+  }

+}

+

+

+/*

+ * Initialize the error-limiting transfer function (lookup table).

+ * The raw F-S error computation can potentially compute error values of up to

+ * +- MAXJSAMPLE.  But we want the maximum correction applied to a pixel to be

+ * much less, otherwise obviously wrong pixels will be created.  (Typical

+ * effects include weird fringes at color-area boundaries, isolated bright

+ * pixels in a dark area, etc.)  The standard advice for avoiding this problem

+ * is to ensure that the "corners" of the color cube are allocated as output

+ * colors; then repeated errors in the same direction cannot cause cascading

+ * error buildup.  However, that only prevents the error from getting

+ * completely out of hand; Aaron Giles reports that error limiting improves

+ * the results even with corner colors allocated.

+ * A simple clamping of the error values to about +- MAXJSAMPLE/8 works pretty

+ * well, but the smoother transfer function used below is even better.  Thanks

+ * to Aaron Giles for this idea.

+ */

+

+LOCAL void

+init_error_limit (j_decompress_ptr cinfo)

+/* Allocate and fill in the error_limiter table */

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  int * table;

+  int in, out;

+

+  table = (int *) (*cinfo->mem->alloc_small)

+    ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * SIZEOF(int));

+  table += MAXJSAMPLE;		/* so can index -MAXJSAMPLE .. +MAXJSAMPLE */

+  cquantize->error_limiter = table;

+

+#define STEPSIZE ((MAXJSAMPLE+1)/16)

+  /* Map errors 1:1 up to +- MAXJSAMPLE/16 */

+  out = 0;

+  for (in = 0; in < STEPSIZE; in++, out++) {

+    table[in] = out; table[-in] = -out;

+  }

+  /* Map errors 1:2 up to +- 3*MAXJSAMPLE/16 */

+  for (; in < STEPSIZE*3; in++, out += (in&1) ? 0 : 1) {

+    table[in] = out; table[-in] = -out;

+  }

+  /* Clamp the rest to final out value (which is (MAXJSAMPLE+1)/8) */

+  for (; in <= MAXJSAMPLE; in++) {

+    table[in] = out; table[-in] = -out;

+  }

+#undef STEPSIZE

+}

+

+

+/*

+ * Finish up at the end of each pass.

+ */

+

+METHODDEF void

+finish_pass1 (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+

+  /* Select the representative colors and fill in cinfo->colormap */

+  cinfo->colormap = cquantize->sv_colormap;

+  select_colors(cinfo, cquantize->desired);

+  /* Force next pass to zero the color index table */

+  cquantize->needs_zeroed = TRUE;

+}

+

+

+METHODDEF void

+finish_pass2 (j_decompress_ptr cinfo)

+{

+  /* no work */

+}

+

+

+/*

+ * Initialize for each processing pass.

+ */

+

+METHODDEF void

+start_pass_2_quant (j_decompress_ptr cinfo, boolean is_pre_scan)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+  hist3d histogram = cquantize->histogram;

+  int i;

+

+  /* Only F-S dithering or no dithering is supported. */

+  /* If user asks for ordered dither, give him F-S. */

+  if (cinfo->dither_mode != JDITHER_NONE)

+    cinfo->dither_mode = JDITHER_FS;

+

+  if (is_pre_scan) {

+    /* Set up method pointers */

+    cquantize->pub.color_quantize = prescan_quantize;

+    cquantize->pub.finish_pass = finish_pass1;

+    cquantize->needs_zeroed = TRUE; /* Always zero histogram */

+  } else {

+    /* Set up method pointers */

+    if (cinfo->dither_mode == JDITHER_FS)

+      cquantize->pub.color_quantize = pass2_fs_dither;

+    else

+      cquantize->pub.color_quantize = pass2_no_dither;

+    cquantize->pub.finish_pass = finish_pass2;

+

+    /* Make sure color count is acceptable */

+    i = cinfo->actual_number_of_colors;

+    if (i < 1)

+      ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 1);

+    if (i > MAXNUMCOLORS)

+      ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS);

+

+    if (cinfo->dither_mode == JDITHER_FS) {

+      size_t arraysize = (size_t) ((cinfo->output_width + 2) *

+				   (3 * SIZEOF(FSERROR)));

+      /* Allocate Floyd-Steinberg workspace if we didn't already. */

+      if (cquantize->fserrors == NULL)

+	cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)

+	  ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize);

+      /* Initialize the propagated errors to zero. */

+      jzero_far((void FAR *) cquantize->fserrors, arraysize);

+      /* Make the error-limit table if we didn't already. */

+      if (cquantize->error_limiter == NULL)

+	init_error_limit(cinfo);

+      cquantize->on_odd_row = FALSE;

+    }

+

+  }

+  /* Zero the histogram or inverse color map, if necessary */

+  if (cquantize->needs_zeroed) {

+    for (i = 0; i < HIST_C0_ELEMS; i++) {

+      jzero_far((void FAR *) histogram[i],

+		HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell));

+    }

+    cquantize->needs_zeroed = FALSE;

+  }

+}

+

+

+/*

+ * Switch to a new external colormap between output passes.

+ */

+

+METHODDEF void

+new_color_map_2_quant (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;

+

+  /* Reset the inverse color map */

+  cquantize->needs_zeroed = TRUE;

+}

+

+

+/*

+ * Module initialization routine for 2-pass color quantization.

+ */

+

+GLOBAL void

+jinit_2pass_quantizer (j_decompress_ptr cinfo)

+{

+  my_cquantize_ptr cquantize;

+  int i;

+

+  cquantize = (my_cquantize_ptr)

+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

+				SIZEOF(my_cquantizer));

+  cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize;

+  cquantize->pub.start_pass = start_pass_2_quant;

+  cquantize->pub.new_color_map = new_color_map_2_quant;

+  cquantize->fserrors = NULL;	/* flag optional arrays not allocated */

+  cquantize->error_limiter = NULL;

+

+  /* Make sure jdmaster didn't give me a case I can't handle */

+  if (cinfo->out_color_components != 3)

+    ERREXIT(cinfo, JERR_NOTIMPL);

+

+  /* Allocate the histogram/inverse colormap storage */

+  cquantize->histogram = (hist3d) (*cinfo->mem->alloc_small)

+    ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * SIZEOF(hist2d));

+  for (i = 0; i < HIST_C0_ELEMS; i++) {

+    cquantize->histogram[i] = (hist2d) (*cinfo->mem->alloc_large)

+      ((j_common_ptr) cinfo, JPOOL_IMAGE,

+       HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell));

+  }

+  cquantize->needs_zeroed = TRUE; /* histogram is garbage now */

+

+  /* Allocate storage for the completed colormap, if required.

+   * We do this now since it is FAR storage and may affect

+   * the memory manager's space calculations.

+   */

+  if (cinfo->enable_2pass_quant) {

+    /* Make sure color count is acceptable */

+    int desired = cinfo->desired_number_of_colors;

+    /* Lower bound on # of colors ... somewhat arbitrary as long as > 0 */

+    if (desired < 8)

+      ERREXIT1(cinfo, JERR_QUANT_FEW_COLORS, 8);

+    /* Make sure colormap indexes can be represented by JSAMPLEs */

+    if (desired > MAXNUMCOLORS)

+      ERREXIT1(cinfo, JERR_QUANT_MANY_COLORS, MAXNUMCOLORS);

+    cquantize->sv_colormap = (*cinfo->mem->alloc_sarray)

+      ((j_common_ptr) cinfo,JPOOL_IMAGE, (JDIMENSION) desired, (JDIMENSION) 3);

+    cquantize->desired = desired;

+  } else

+    cquantize->sv_colormap = NULL;

+

+  /* Only F-S dithering or no dithering is supported. */

+  /* If user asks for ordered dither, give him F-S. */

+  if (cinfo->dither_mode != JDITHER_NONE)

+    cinfo->dither_mode = JDITHER_FS;

+

+  /* Allocate Floyd-Steinberg workspace if necessary.

+   * This isn't really needed until pass 2, but again it is FAR storage.

+   * Although we will cope with a later change in dither_mode,

+   * we do not promise to honor max_memory_to_use if dither_mode changes.

+   */

+  if (cinfo->dither_mode == JDITHER_FS) {

+    cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)

+      ((j_common_ptr) cinfo, JPOOL_IMAGE,

+       (size_t) ((cinfo->output_width + 2) * (3 * SIZEOF(FSERROR))));

+    /* Might as well create the error-limiting table too. */

+    init_error_limit(cinfo);

+  }

+}

+

+#endif /* QUANT_2PASS_SUPPORTED */

diff --git a/code/jpeg-6/jutils.c b/code/jpeg-6/jutils.c
new file mode 100755
index 0000000..8e8dc13
--- /dev/null
+++ b/code/jpeg-6/jutils.c
@@ -0,0 +1,175 @@
+/*

+ * jutils.c

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains tables and miscellaneous utility routines needed

+ * for both compression and decompression.

+ * Note we prefix all global names with "j" to minimize conflicts with

+ * a surrounding application.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * jpeg_zigzag_order[i] is the zigzag-order position of the i'th element

+ * of a DCT block read in natural order (left to right, top to bottom).

+ */

+

+const int jpeg_zigzag_order[DCTSIZE2] = {

+   0,  1,  5,  6, 14, 15, 27, 28,

+   2,  4,  7, 13, 16, 26, 29, 42,

+   3,  8, 12, 17, 25, 30, 41, 43,

+   9, 11, 18, 24, 31, 40, 44, 53,

+  10, 19, 23, 32, 39, 45, 52, 54,

+  20, 22, 33, 38, 46, 51, 55, 60,

+  21, 34, 37, 47, 50, 56, 59, 61,

+  35, 36, 48, 49, 57, 58, 62, 63

+};

+

+/*

+ * jpeg_natural_order[i] is the natural-order position of the i'th element

+ * of zigzag order.

+ *

+ * When reading corrupted data, the Huffman decoders could attempt

+ * to reference an entry beyond the end of this array (if the decoded

+ * zero run length reaches past the end of the block).  To prevent

+ * wild stores without adding an inner-loop test, we put some extra

+ * "63"s after the real entries.  This will cause the extra coefficient

+ * to be stored in location 63 of the block, not somewhere random.

+ * The worst case would be a run-length of 15, which means we need 16

+ * fake entries.

+ */

+

+const int jpeg_natural_order[DCTSIZE2+16] = {

+  0,  1,  8, 16,  9,  2,  3, 10,

+ 17, 24, 32, 25, 18, 11,  4,  5,

+ 12, 19, 26, 33, 40, 48, 41, 34,

+ 27, 20, 13,  6,  7, 14, 21, 28,

+ 35, 42, 49, 56, 57, 50, 43, 36,

+ 29, 22, 15, 23, 30, 37, 44, 51,

+ 58, 59, 52, 45, 38, 31, 39, 46,

+ 53, 60, 61, 54, 47, 55, 62, 63,

+ 63, 63, 63, 63, 63, 63, 63, 63, /* extra entries for safety in decoder */

+ 63, 63, 63, 63, 63, 63, 63, 63

+};

+

+

+/*

+ * Arithmetic utilities

+ */

+

+GLOBAL long

+jdiv_round_up (long a, long b)

+/* Compute a/b rounded up to next integer, ie, ceil(a/b) */

+/* Assumes a >= 0, b > 0 */

+{

+  return (a + b - 1L) / b;

+}

+

+

+GLOBAL long

+jround_up (long a, long b)

+/* Compute a rounded up to next multiple of b, ie, ceil(a/b)*b */

+/* Assumes a >= 0, b > 0 */

+{

+  a += b - 1L;

+  return a - (a % b);

+}

+

+

+/* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays

+ * and coefficient-block arrays.  This won't work on 80x86 because the arrays

+ * are FAR and we're assuming a small-pointer memory model.  However, some

+ * DOS compilers provide far-pointer versions of memcpy() and memset() even

+ * in the small-model libraries.  These will be used if USE_FMEM is defined.

+ * Otherwise, the routines below do it the hard way.  (The performance cost

+ * is not all that great, because these routines aren't very heavily used.)

+ */

+

+#ifndef NEED_FAR_POINTERS	/* normal case, same as regular macros */

+#define FMEMCOPY(dest,src,size)	MEMCOPY(dest,src,size)

+#define FMEMZERO(target,size)	MEMZERO(target,size)

+#else				/* 80x86 case, define if we can */

+#ifdef USE_FMEM

+#define FMEMCOPY(dest,src,size)	_fmemcpy((void FAR *)(dest), (const void FAR *)(src), (size_t)(size))

+#define FMEMZERO(target,size)	_fmemset((void FAR *)(target), 0, (size_t)(size))

+#endif

+#endif

+

+

+GLOBAL void

+jcopy_sample_rows (JSAMPARRAY input_array, int source_row,

+		   JSAMPARRAY output_array, int dest_row,

+		   int num_rows, JDIMENSION num_cols)

+/* Copy some rows of samples from one place to another.

+ * num_rows rows are copied from input_array[source_row++]

+ * to output_array[dest_row++]; these areas may overlap for duplication.

+ * The source and destination arrays must be at least as wide as num_cols.

+ */

+{

+  register JSAMPROW inptr, outptr;

+#ifdef FMEMCOPY

+  register size_t count = (size_t) (num_cols * SIZEOF(JSAMPLE));

+#else

+  register JDIMENSION count;

+#endif

+  register int row;

+

+  input_array += source_row;

+  output_array += dest_row;

+

+  for (row = num_rows; row > 0; row--) {

+    inptr = *input_array++;

+    outptr = *output_array++;

+#ifdef FMEMCOPY

+    FMEMCOPY(outptr, inptr, count);

+#else

+    for (count = num_cols; count > 0; count--)

+      *outptr++ = *inptr++;	/* needn't bother with GETJSAMPLE() here */

+#endif

+  }

+}

+

+

+GLOBAL void

+jcopy_block_row (JBLOCKROW input_row, JBLOCKROW output_row,

+		 JDIMENSION num_blocks)

+/* Copy a row of coefficient blocks from one place to another. */

+{

+#ifdef FMEMCOPY

+  FMEMCOPY(output_row, input_row, num_blocks * (DCTSIZE2 * SIZEOF(JCOEF)));

+#else

+  register JCOEFPTR inptr, outptr;

+  register long count;

+

+  inptr = (JCOEFPTR) input_row;

+  outptr = (JCOEFPTR) output_row;

+  for (count = (long) num_blocks * DCTSIZE2; count > 0; count--) {

+    *outptr++ = *inptr++;

+  }

+#endif

+}

+

+

+GLOBAL void

+jzero_far (void FAR * target, size_t bytestozero)

+/* Zero out a chunk of FAR memory. */

+/* This might be sample-array data, block-array data, or alloc_large data. */

+{

+#ifdef FMEMZERO

+  FMEMZERO(target, bytestozero);

+#else

+  register char FAR * ptr = (char FAR *) target;

+  register size_t count;

+

+  for (count = bytestozero; count > 0; count--) {

+    *ptr++ = 0;

+  }

+#endif

+}

diff --git a/code/jpeg-6/jversion.h b/code/jpeg-6/jversion.h
new file mode 100755
index 0000000..02083ac
--- /dev/null
+++ b/code/jpeg-6/jversion.h
@@ -0,0 +1,14 @@
+/*

+ * jversion.h

+ *

+ * Copyright (C) 1991-1995, Thomas G. Lane.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains software version identification.

+ */

+

+

+#define JVERSION	"6  2-Aug-95"

+

+#define JCOPYRIGHT	"Copyright (C) 1995, Thomas G. Lane"