FFmpeg: libavcodec/ac3tab.c Source File

FFmpeg
ac3tab.c
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1 /*
2  * AC-3 tables
3  * copyright (c) 2001 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * tables taken directly from the AC-3 spec.
25  */
26 
27 #include "libavutil/channel_layout.h"
28 #include "libavutil/mathematics.h"
29 
30 #include "ac3tab.h"
31 
32 /**
33  * Possible frame sizes.
34  * from ATSC A/52 Table 5.18 Frame Size Code Table.
35  */
36  const uint16_t ff_ac3_frame_size_tab[38][3] = {
37  { 64, 69, 96 },
38  { 64, 70, 96 },
39  { 80, 87, 120 },
40  { 80, 88, 120 },
41  { 96, 104, 144 },
42  { 96, 105, 144 },
43  { 112, 121, 168 },
44  { 112, 122, 168 },
45  { 128, 139, 192 },
46  { 128, 140, 192 },
47  { 160, 174, 240 },
48  { 160, 175, 240 },
49  { 192, 208, 288 },
50  { 192, 209, 288 },
51  { 224, 243, 336 },
52  { 224, 244, 336 },
53  { 256, 278, 384 },
54  { 256, 279, 384 },
55  { 320, 348, 480 },
56  { 320, 349, 480 },
57  { 384, 417, 576 },
58  { 384, 418, 576 },
59  { 448, 487, 672 },
60  { 448, 488, 672 },
61  { 512, 557, 768 },
62  { 512, 558, 768 },
63  { 640, 696, 960 },
64  { 640, 697, 960 },
65  { 768, 835, 1152 },
66  { 768, 836, 1152 },
67  { 896, 975, 1344 },
68  { 896, 976, 1344 },
69  { 1024, 1114, 1536 },
70  { 1024, 1115, 1536 },
71  { 1152, 1253, 1728 },
72  { 1152, 1254, 1728 },
73  { 1280, 1393, 1920 },
74  { 1280, 1394, 1920 },
75 };
76 
77 /**
78  * Map audio coding mode (acmod) to number of full-bandwidth channels.
79  * from ATSC A/52 Table 5.8 Audio Coding Mode
80  */
81  const uint8_t ff_ac3_channels_tab[8] = {
82  2, 1, 2, 3, 3, 4, 4, 5
83 };
84 
85 /**
86  * Table to remap channels from AC-3 order to SMPTE order.
87  * [channel_mode][lfe][ch]
88  */
89  const uint8_t ff_ac3_dec_channel_map[8][2][6] = {
90  COMMON_CHANNEL_MAP
91  { { 0, 1, 2, 3, }, { 0, 1, 4, 2, 3, } },
92  { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 5, 3, 4 } },
93 };
94 
95 /* possible frequencies */
96  const int ff_ac3_sample_rate_tab[] = { 48000, 44100, 32000, 0 };
97 
98 /* possible bitrates */
99  const uint16_t ff_ac3_bitrate_tab[19] = {
100  32, 40, 48, 56, 64, 80, 96, 112, 128,
101  160, 192, 224, 256, 320, 384, 448, 512, 576, 640
102 };
103 
104 /**
105  * Table of bin locations for rematrixing bands
106  * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
107  */
108  const uint8_t ff_ac3_rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };
109 
110 /**
111  * Table E2.16 Default Coupling Banding Structure
112  */
113  const uint8_t ff_eac3_default_cpl_band_struct[18] = {
114  0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1
115 };
116 
117  const uint8_t ff_ac3_bap_tab[64]= {
118  0, 1, 1, 1, 1, 1, 2, 2, 3, 3,
119  3, 4, 4, 5, 5, 6, 6, 6, 6, 7,
120  7, 7, 7, 8, 8, 8, 8, 9, 9, 9,
121  9, 10, 10, 10, 10, 11, 11, 11, 11, 12,
122  12, 12, 12, 13, 13, 13, 13, 14, 14, 14,
123  14, 14, 14, 14, 14, 15, 15, 15, 15, 15,
124  15, 15, 15, 15,
125 };
126 
127  const uint8_t ff_ac3_slow_decay_tab[4]={
128  0x0f, 0x11, 0x13, 0x15,
129 };
130 
131  const uint8_t ff_ac3_fast_decay_tab[4]={
132  0x3f, 0x53, 0x67, 0x7b,
133 };
134 
135  const uint16_t ff_ac3_slow_gain_tab[4]= {
136  0x540, 0x4d8, 0x478, 0x410,
137 };
138 
139  const uint16_t ff_ac3_db_per_bit_tab[4]= {
140  0x000, 0x700, 0x900, 0xb00,
141 };
142 
143  const int16_t ff_ac3_floor_tab[8]= {
144  0x2f0, 0x2b0, 0x270, 0x230, 0x1f0, 0x170, 0x0f0, 0xf800,
145 };
146 
147  const uint16_t ff_ac3_fast_gain_tab[8]= {
148  0x080, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400,
149 };
150 
151 /** Adjustments in dB gain */
152  const float ff_ac3_gain_levels[9] = {
153  LEVEL_PLUS_3DB,
154  LEVEL_PLUS_1POINT5DB,
155  LEVEL_ONE,
156  LEVEL_MINUS_1POINT5DB,
157  LEVEL_MINUS_3DB,
158  LEVEL_MINUS_4POINT5DB,
159  LEVEL_MINUS_6DB,
160  LEVEL_ZERO,
161  LEVEL_MINUS_9DB
162 };
163 
164  const uint64_t ff_eac3_custom_channel_map_locations[16][2] = {
165  { 1, AV_CH_FRONT_LEFT },
166  { 1, AV_CH_FRONT_CENTER },
167  { 1, AV_CH_FRONT_RIGHT },
168  { 1, AV_CH_SIDE_LEFT },
169  { 1, AV_CH_SIDE_RIGHT },
170  { 0, AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER },
171  { 0, AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT },
172  { 0, AV_CH_BACK_CENTER },
173  { 0, AV_CH_TOP_CENTER },
174  { 0, AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT },
175  { 0, AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT },
176  { 0, AV_CH_TOP_FRONT_LEFT | AV_CH_TOP_FRONT_RIGHT},
177  { 0, AV_CH_TOP_FRONT_CENTER },
178  { 0, AV_CH_TOP_BACK_LEFT | AV_CH_TOP_BACK_RIGHT },
179  { 0, AV_CH_LOW_FREQUENCY_2 },
180  { 1, AV_CH_LOW_FREQUENCY },
181 };
LEVEL_PLUS_3DB
#define LEVEL_PLUS_3DB
Definition: ac3defs.h:40
ff_ac3_fast_decay_tab
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:131
AV_CH_TOP_FRONT_CENTER
#define AV_CH_TOP_FRONT_CENTER
Definition: channel_layout.h:188
AV_CH_LOW_FREQUENCY_2
#define AV_CH_LOW_FREQUENCY_2
Definition: channel_layout.h:199
LEVEL_MINUS_4POINT5DB
#define LEVEL_MINUS_4POINT5DB
Definition: ac3defs.h:44
COMMON_CHANNEL_MAP
#define COMMON_CHANNEL_MAP
Definition: ac3tab.h:53
AV_CH_TOP_FRONT_RIGHT
#define AV_CH_TOP_FRONT_RIGHT
Definition: channel_layout.h:189
ff_ac3_channels_tab
const uint8_t ff_ac3_channels_tab[8]
Map audio coding mode (acmod) to number of full-bandwidth channels.
Definition: ac3tab.c:81
AV_CH_TOP_FRONT_LEFT
#define AV_CH_TOP_FRONT_LEFT
Definition: channel_layout.h:187
mathematics.h
AV_CH_WIDE_LEFT
#define AV_CH_WIDE_LEFT
Definition: channel_layout.h:195
AV_CH_SURROUND_DIRECT_RIGHT
#define AV_CH_SURROUND_DIRECT_RIGHT
Definition: channel_layout.h:198
LEVEL_ZERO
#define LEVEL_ZERO
Definition: ac3defs.h:47
AV_CH_WIDE_RIGHT
#define AV_CH_WIDE_RIGHT
Definition: channel_layout.h:196
AV_CH_TOP_BACK_LEFT
#define AV_CH_TOP_BACK_LEFT
Definition: channel_layout.h:190
AV_CH_BACK_LEFT
#define AV_CH_BACK_LEFT
Definition: channel_layout.h:179
LEVEL_MINUS_3DB
#define LEVEL_MINUS_3DB
Definition: ac3defs.h:43
ff_ac3_bap_tab
const uint8_t ff_ac3_bap_tab[64]
Definition: ac3tab.c:117
ff_ac3_dec_channel_map
const uint8_t ff_ac3_dec_channel_map[8][2][6]
Table to remap channels from AC-3 order to SMPTE order.
Definition: ac3tab.c:89
LEVEL_MINUS_9DB
#define LEVEL_MINUS_9DB
Definition: ac3defs.h:46
AV_CH_LOW_FREQUENCY
#define AV_CH_LOW_FREQUENCY
Definition: channel_layout.h:178
ff_ac3_gain_levels
const float ff_ac3_gain_levels[9]
Adjustments in dB gain.
Definition: ac3tab.c:152
ff_ac3_floor_tab
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:143
AV_CH_TOP_CENTER
#define AV_CH_TOP_CENTER
Definition: channel_layout.h:186
AV_CH_FRONT_CENTER
#define AV_CH_FRONT_CENTER
Definition: channel_layout.h:177
AV_CH_FRONT_LEFT_OF_CENTER
#define AV_CH_FRONT_LEFT_OF_CENTER
Definition: channel_layout.h:181
ff_eac3_custom_channel_map_locations
const uint64_t ff_eac3_custom_channel_map_locations[16][2]
Definition: ac3tab.c:164
ff_ac3_db_per_bit_tab
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:139
LEVEL_ONE
#define LEVEL_ONE
Definition: ac3defs.h:48
AV_CH_TOP_BACK_RIGHT
#define AV_CH_TOP_BACK_RIGHT
Definition: channel_layout.h:192
AV_CH_FRONT_RIGHT_OF_CENTER
#define AV_CH_FRONT_RIGHT_OF_CENTER
Definition: channel_layout.h:182
ff_ac3_rematrix_band_tab
const uint8_t ff_ac3_rematrix_band_tab[5]
Table of bin locations for rematrixing bands reference: Section 7.5.2 Rematrixing : Frequency Band De...
Definition: ac3tab.c:108
ff_ac3_sample_rate_tab
const int ff_ac3_sample_rate_tab[]
Definition: ac3tab.c:96
LEVEL_MINUS_1POINT5DB
#define LEVEL_MINUS_1POINT5DB
Definition: ac3defs.h:42
ff_ac3_slow_decay_tab
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:127
AV_CH_BACK_CENTER
#define AV_CH_BACK_CENTER
Definition: channel_layout.h:183
AV_CH_FRONT_LEFT
#define AV_CH_FRONT_LEFT
Definition: channel_layout.h:175
AV_CH_SIDE_RIGHT
#define AV_CH_SIDE_RIGHT
Definition: channel_layout.h:185
ff_ac3_frame_size_tab
const uint16_t ff_ac3_frame_size_tab[38][3]
Possible frame sizes.
Definition: ac3tab.c:36
channel_layout.h
LEVEL_MINUS_6DB
#define LEVEL_MINUS_6DB
Definition: ac3defs.h:45
ff_ac3_bitrate_tab
const uint16_t ff_ac3_bitrate_tab[19]
Definition: ac3tab.c:99
AV_CH_SURROUND_DIRECT_LEFT
#define AV_CH_SURROUND_DIRECT_LEFT
Definition: channel_layout.h:197
AV_CH_FRONT_RIGHT
#define AV_CH_FRONT_RIGHT
Definition: channel_layout.h:176
LEVEL_PLUS_1POINT5DB
#define LEVEL_PLUS_1POINT5DB
Definition: ac3defs.h:41
ff_ac3_slow_gain_tab
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:135
ff_ac3_fast_gain_tab
const uint16_t ff_ac3_fast_gain_tab[8]
Definition: ac3tab.c:147
AV_CH_BACK_RIGHT
#define AV_CH_BACK_RIGHT
Definition: channel_layout.h:180
ac3tab.h
AV_CH_SIDE_LEFT
#define AV_CH_SIDE_LEFT
Definition: channel_layout.h:184
ff_eac3_default_cpl_band_struct
const uint8_t ff_eac3_default_cpl_band_struct[18]
Table E2.16 Default Coupling Banding Structure.
Definition: ac3tab.c:113
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