PageRenderTime 20ms CodeModel.GetById 9ms app.highlight 6ms RepoModel.GetById 1ms app.codeStats 0ms

/media/libvorbis/lib/mdct.h

http://github.com/zpao/v8monkey
C Header | 71 lines | 35 code | 19 blank | 17 comment | 0 complexity | c4734260aa22475387cfa53ed44c3e88 MD5 | raw file
 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 1994-2009             *
 9 * by the Xiph.Org Foundation http://www.xiph.org/                  *
10 *                                                                  *
11 ********************************************************************
12
13 function: modified discrete cosine transform prototypes
14 last mod: $Id: mdct.h 16227 2009-07-08 06:58:46Z xiphmont $
15
16 ********************************************************************/
17
18#ifndef _OGG_mdct_H_
19#define _OGG_mdct_H_
20
21#include "vorbis/codec.h"
22
23
24
25
26
27/*#define MDCT_INTEGERIZED  <- be warned there could be some hurt left here*/
28#ifdef MDCT_INTEGERIZED
29
30#define DATA_TYPE int
31#define REG_TYPE  register int
32#define TRIGBITS 14
33#define cPI3_8 6270
34#define cPI2_8 11585
35#define cPI1_8 15137
36
37#define FLOAT_CONV(x) ((int)((x)*(1<<TRIGBITS)+.5))
38#define MULT_NORM(x) ((x)>>TRIGBITS)
39#define HALVE(x) ((x)>>1)
40
41#else
42
43#define DATA_TYPE float
44#define REG_TYPE  float
45#define cPI3_8 .38268343236508977175F
46#define cPI2_8 .70710678118654752441F
47#define cPI1_8 .92387953251128675613F
48
49#define FLOAT_CONV(x) (x)
50#define MULT_NORM(x) (x)
51#define HALVE(x) ((x)*.5f)
52
53#endif
54
55
56typedef struct {
57  int n;
58  int log2n;
59
60  DATA_TYPE *trig;
61  int       *bitrev;
62
63  DATA_TYPE scale;
64} mdct_lookup;
65
66extern void mdct_init(mdct_lookup *lookup,int n);
67extern void mdct_clear(mdct_lookup *l);
68extern void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
69extern void mdct_backward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out);
70
71#endif