/******************************************************************** * * * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * * * * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 * * by the XIPHOPHORUS Company http://www.xiph.org/ * * * ******************************************************************** function: fft transform last mod: $Id: smallft.h,v 1.3 2003/09/16 18:35:45 jm Exp $ ********************************************************************/ /** @file smallft.h @brief Discrete Rotational Fourier Transform (DRFT) */ #ifndef _V_SMFT_H_ #define _V_SMFT_H_ #ifdef __cplusplus extern "C" { #endif /** Discrete Rotational Fourier Transform lookup */ struct drft_lookup{ int n; float *trigcache; int *splitcache; }; extern void spx_drft_forward(struct drft_lookup *l,float *data); extern void spx_drft_backward(struct drft_lookup *l,float *data); extern void spx_drft_init(struct drft_lookup *l,int n); extern void spx_drft_clear(struct drft_lookup *l); #ifdef __cplusplus } #endif #endif