1 /********************************************************************
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. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: fft transform
14 last mod: $Id: smallft.h,v 1.3 2003/09/16 18:35:45 jm Exp $
16 ********************************************************************/
19 @brief Discrete Rotational Fourier Transform (DRFT)
30 /** Discrete Rotational Fourier Transform lookup */
37 extern void spx_drft_forward(struct drft_lookup *l,float *data);
38 extern void spx_drft_backward(struct drft_lookup *l,float *data);
39 extern void spx_drft_init(struct drft_lookup *l,int n);
40 extern void spx_drft_clear(struct drft_lookup *l);