6833f3c70a9bae8aaa7a8806946428bcb0f314eb
[libav.git] / libavcodec / mpegaudiotab.h
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 mpegaudiotab.h
26 * mpeg audio layer 2 tables.
27 * Most of them come from the mpeg audio specification.
28 */
29
30 #include <stdint.h>
31 #include "mpegaudio.h"
32
33 #define SQRT2 1.41421356237309514547
34
35 static const int costab32[30] = {
36 FIX(0.54119610014619701222),
37 FIX(1.3065629648763763537),
38
39 FIX(0.50979557910415917998),
40 FIX(2.5629154477415054814),
41 FIX(0.89997622313641556513),
42 FIX(0.60134488693504528634),
43
44 FIX(0.5024192861881556782),
45 FIX(5.1011486186891552563),
46 FIX(0.78815462345125020249),
47 FIX(0.64682178335999007679),
48 FIX(0.56694403481635768927),
49 FIX(1.0606776859903470633),
50 FIX(1.7224470982383341955),
51 FIX(0.52249861493968885462),
52
53 FIX(10.19000812354803287),
54 FIX(0.674808341455005678),
55 FIX(1.1694399334328846596),
56 FIX(0.53104259108978413284),
57 FIX(2.0577810099534108446),
58 FIX(0.58293496820613388554),
59 FIX(0.83934964541552681272),
60 FIX(0.50547095989754364798),
61 FIX(3.4076084184687189804),
62 FIX(0.62250412303566482475),
63 FIX(0.97256823786196078263),
64 FIX(0.51544730992262455249),
65 FIX(1.4841646163141661852),
66 FIX(0.5531038960344445421),
67 FIX(0.74453627100229857749),
68 FIX(0.5006029982351962726),
69 };
70
71 static const int bitinv32[32] = {
72 0, 16, 8, 24, 4, 20, 12, 28,
73 2, 18, 10, 26, 6, 22, 14, 30,
74 1, 17, 9, 25, 5, 21, 13, 29,
75 3, 19, 11, 27, 7, 23, 15, 31
76 };
77
78
79 static int16_t filter_bank[512];
80
81 static int scale_factor_table[64];
82 #ifdef USE_FLOATS
83 static float scale_factor_inv_table[64];
84 #else
85 static int8_t scale_factor_shift[64];
86 static unsigned short scale_factor_mult[64];
87 #endif
88 static unsigned char scale_diff_table[128];
89
90 /* total number of bits per allocation group */
91 static unsigned short total_quant_bits[17];
92
93 /* signal to noise ratio of each quantification step (could be
94 computed from quant_steps[]). The values are dB multiplied by 10
95 */
96 static const unsigned short quant_snr[17] = {
97 70, 110, 160, 208,
98 253, 316, 378, 439,
99 499, 559, 620, 680,
100 740, 800, 861, 920,
101 980
102 };
103
104 /* fixed psycho acoustic model. Values of SNR taken from the 'toolame'
105 project */
106 static const float fixed_smr[SBLIMIT] = {
107 30, 17, 16, 10, 3, 12, 8, 2.5,
108 5, 5, 6, 6, 5, 6, 10, 6,
109 -4, -10, -21, -30, -42, -55, -68, -75,
110 -75, -75, -75, -75, -91, -107, -110, -108
111 };
112
113 static const unsigned char nb_scale_factors[4] = { 3, 2, 1, 2 };
114