cannam@86: /********************************************************************
cannam@86:  *                                                                  *
cannam@86:  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
cannam@86:  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
cannam@86:  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
cannam@86:  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
cannam@86:  *                                                                  *
cannam@86:  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009             *
cannam@86:  * by the Xiph.Org Foundation http://www.xiph.org/                  *
cannam@86:  *                                                                  *
cannam@86:  ********************************************************************
cannam@86: 
cannam@86:  function: modified discrete cosine transform prototypes
cannam@86:  last mod: $Id: mdct.h 16227 2009-07-08 06:58:46Z xiphmont $
cannam@86: 
cannam@86:  ********************************************************************/
cannam@86: 
cannam@86: #ifndef _OGG_mdct_H_
cannam@86: #define _OGG_mdct_H_
cannam@86: 
cannam@86: #include "vorbis/codec.h"
cannam@86: 
cannam@86: 
cannam@86: 
cannam@86: 
cannam@86: 
cannam@86: /*#define MDCT_INTEGERIZED  <- be warned there could be some hurt left here*/
cannam@86: #ifdef MDCT_INTEGERIZED
cannam@86: 
cannam@86: #define DATA_TYPE int
cannam@86: #define REG_TYPE  register int
cannam@86: #define TRIGBITS 14
cannam@86: #define cPI3_8 6270
cannam@86: #define cPI2_8 11585
cannam@86: #define cPI1_8 15137
cannam@86: 
cannam@86: #define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5))
cannam@86: #define MULT_NORM(x) ((x)>>TRIGBITS)
cannam@86: #define HALVE(x) ((x)>>1)
cannam@86: 
cannam@86: #else
cannam@86: 
cannam@86: #define DATA_TYPE float
cannam@86: #define REG_TYPE  float
cannam@86: #define cPI3_8 .38268343236508977175F
cannam@86: #define cPI2_8 .70710678118654752441F
cannam@86: #define cPI1_8 .92387953251128675613F
cannam@86: 
cannam@86: #define FLOAT_CONV(x) (x)
cannam@86: #define MULT_NORM(x) (x)
cannam@86: #define HALVE(x) ((x)*.5f)
cannam@86: 
cannam@86: #endif
cannam@86: 
cannam@86: 
cannam@86: typedef struct {
cannam@86:   int n;
cannam@86:   int log2n;
cannam@86: 
cannam@86:   DATA_TYPE *trig;
cannam@86:   int       *bitrev;
cannam@86: 
cannam@86:   DATA_TYPE scale;
cannam@86: } mdct_lookup;
cannam@86: 
cannam@86: extern void mdct_init(mdct_lookup *lookup,int n);
cannam@86: extern void mdct_clear(mdct_lookup *l);
cannam@86: extern void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
cannam@86: extern void mdct_backward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
cannam@86: 
cannam@86: #endif