FFmpeg
mpegaudiotab.h
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1 /*
2  * mpeg audio layer 2 tables. Most of them come from the mpeg audio
3  * specification.
4  *
5  * Copyright (c) 2000, 2001 Fabrice Bellard
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 /**
25  * @file
26  * mpeg audio layer 2 tables.
27  * Most of them come from the mpeg audio specification.
28  */
29 
30 #ifndef AVCODEC_MPEGAUDIOTAB_H
31 #define AVCODEC_MPEGAUDIOTAB_H
32 
33 #include <stdint.h>
34 #include "mpegaudio.h"
35 
36 static const int costab32[30] = {
37  FIX(0.54119610014619701222),
38  FIX(1.3065629648763763537),
39 
40  FIX(0.50979557910415917998),
41  FIX(2.5629154477415054814),
42  FIX(0.89997622313641556513),
43  FIX(0.60134488693504528634),
44 
45  FIX(0.5024192861881556782),
46  FIX(5.1011486186891552563),
47  FIX(0.78815462345125020249),
48  FIX(0.64682178335999007679),
49  FIX(0.56694403481635768927),
50  FIX(1.0606776859903470633),
51  FIX(1.7224470982383341955),
52  FIX(0.52249861493968885462),
53 
54  FIX(10.19000812354803287),
55  FIX(0.674808341455005678),
56  FIX(1.1694399334328846596),
57  FIX(0.53104259108978413284),
58  FIX(2.0577810099534108446),
59  FIX(0.58293496820613388554),
60  FIX(0.83934964541552681272),
61  FIX(0.50547095989754364798),
62  FIX(3.4076084184687189804),
63  FIX(0.62250412303566482475),
64  FIX(0.97256823786196078263),
65  FIX(0.51544730992262455249),
66  FIX(1.4841646163141661852),
67  FIX(0.5531038960344445421),
68  FIX(0.74453627100229857749),
69  FIX(0.5006029982351962726),
70 };
71 
72 static const int bitinv32[32] = {
73  0, 16, 8, 24, 4, 20, 12, 28,
74  2, 18, 10, 26, 6, 22, 14, 30,
75  1, 17, 9, 25, 5, 21, 13, 29,
76  3, 19, 11, 27, 7, 23, 15, 31
77 };
78 
79 
80 /* signal to noise ratio of each quantification step (could be
81  computed from quant_steps[]). The values are dB multiplied by 10
82 */
83 static const unsigned short quant_snr[17] = {
84  70, 110, 160, 208,
85  253, 316, 378, 439,
86  499, 559, 620, 680,
87  740, 800, 861, 920,
88  980
89 };
90 
91 /* fixed psycho acoustic model. Values of SNR taken from the 'toolame'
92  project */
93 static const float fixed_smr[SBLIMIT] = {
94  30, 17, 16, 10, 3, 12, 8, 2.5,
95  5, 5, 6, 6, 5, 6, 10, 6,
96  -4, -10, -21, -30, -42, -55, -68, -75,
97  -75, -75, -75, -75, -91, -107, -110, -108
98 };
99 
100 static const unsigned char nb_scale_factors[4] = { 3, 2, 1, 2 };
101 
102 #endif /* AVCODEC_MPEGAUDIOTAB_H */
#define SBLIMIT
Definition: mpegaudio.h:44
static const unsigned char nb_scale_factors[4]
Definition: mpegaudiotab.h:100
static const int costab32[30]
Definition: mpegaudiotab.h:36
#define FIX(x)
Definition: jrevdct.c:146
static const unsigned short quant_snr[17]
Definition: mpegaudiotab.h:83
static const int bitinv32[32]
Definition: mpegaudiotab.h:72
static const float fixed_smr[SBLIMIT]
Definition: mpegaudiotab.h:93
mpeg audio declarations for both encoder and decoder.