| /******************************************************************** |
| * * |
| * 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 |