/******************************************************************** *                                                                  * * 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 __cplusplusextern "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