michael@0: /********************************************************************
michael@0:  *                                                                  *
michael@0:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
michael@0:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
michael@0:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
michael@0:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
michael@0:  *                                                                  *
michael@0:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
michael@0:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
michael@0:  *                                                                  *
michael@0:  ********************************************************************
michael@0: 
michael@0:  function: modified discrete cosine transform prototypes
michael@0:  last mod: $Id: mdct.h 16227 2009-07-08 06:58:46Z xiphmont $
michael@0: 
michael@0:  ********************************************************************/
michael@0: 
michael@0: #ifndef _OGG_mdct_H_
michael@0: #define _OGG_mdct_H_
michael@0: 
michael@0: #include "vorbis/codec.h"
michael@0: 
michael@0: 
michael@0: 
michael@0: 
michael@0: 
michael@0: /*#define MDCT_INTEGERIZED  <- be warned there could be some hurt left here*/
michael@0: #ifdef MDCT_INTEGERIZED
michael@0: 
michael@0: #define DATA_TYPE int
michael@0: #define REG_TYPE  register int
michael@0: #define TRIGBITS 14
michael@0: #define cPI3_8 6270
michael@0: #define cPI2_8 11585
michael@0: #define cPI1_8 15137
michael@0: 
michael@0: #define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5))
michael@0: #define MULT_NORM(x) ((x)>>TRIGBITS)
michael@0: #define HALVE(x) ((x)>>1)
michael@0: 
michael@0: #else
michael@0: 
michael@0: #define DATA_TYPE float
michael@0: #define REG_TYPE  float
michael@0: #define cPI3_8 .38268343236508977175F
michael@0: #define cPI2_8 .70710678118654752441F
michael@0: #define cPI1_8 .92387953251128675613F
michael@0: 
michael@0: #define FLOAT_CONV(x) (x)
michael@0: #define MULT_NORM(x) (x)
michael@0: #define HALVE(x) ((x)*.5f)
michael@0: 
michael@0: #endif
michael@0: 
michael@0: 
michael@0: typedef struct {
michael@0:   int n;
michael@0:   int log2n;
michael@0: 
michael@0:   DATA_TYPE *trig;
michael@0:   int       *bitrev;
michael@0: 
michael@0:   DATA_TYPE scale;
michael@0: } mdct_lookup;
michael@0: 
michael@0: extern void mdct_init(mdct_lookup *lookup,int n);
michael@0: extern void mdct_clear(mdct_lookup *l);
michael@0: extern void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
michael@0: extern void mdct_backward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
michael@0: 
michael@0: #endif