1 /******************************************************************** 2 * * 3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * 4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * 5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * 6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * 7 * * 8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2007 * 9 * by the Xiph.Org Foundation https://xiph.org/ * 10 * * 11 ******************************************************************** 12 13 function: fft transform 14 15 ********************************************************************/ 16 17 #ifndef _V_SMFT_H_ 18 #define _V_SMFT_H_ 19 20 #include "vorbis/codec.h" 21 22 typedef struct { 23 int n; 24 float *trigcache; 25 int *splitcache; 26 } drft_lookup; 27 28 extern void drft_forward(drft_lookup *l,float *data); 29 extern void drft_backward(drft_lookup *l,float *data); 30 extern void drft_init(drft_lookup *l,int n); 31 extern void drft_clear(drft_lookup *l); 32 33 #endif 34