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 
29 #include "ac3.h"
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_log_add_tab[260]= {
118 0x40,0x3f,0x3e,0x3d,0x3c,0x3b,0x3a,0x39,0x38,0x37,
119 0x36,0x35,0x34,0x34,0x33,0x32,0x31,0x30,0x2f,0x2f,
120 0x2e,0x2d,0x2c,0x2c,0x2b,0x2a,0x29,0x29,0x28,0x27,
121 0x26,0x26,0x25,0x24,0x24,0x23,0x23,0x22,0x21,0x21,
122 0x20,0x20,0x1f,0x1e,0x1e,0x1d,0x1d,0x1c,0x1c,0x1b,
123 0x1b,0x1a,0x1a,0x19,0x19,0x18,0x18,0x17,0x17,0x16,
124 0x16,0x15,0x15,0x15,0x14,0x14,0x13,0x13,0x13,0x12,
125 0x12,0x12,0x11,0x11,0x11,0x10,0x10,0x10,0x0f,0x0f,
126 0x0f,0x0e,0x0e,0x0e,0x0d,0x0d,0x0d,0x0d,0x0c,0x0c,
127 0x0c,0x0c,0x0b,0x0b,0x0b,0x0b,0x0a,0x0a,0x0a,0x0a,
128 0x0a,0x09,0x09,0x09,0x09,0x09,0x08,0x08,0x08,0x08,
129 0x08,0x08,0x07,0x07,0x07,0x07,0x07,0x07,0x06,0x06,
130 0x06,0x06,0x06,0x06,0x06,0x06,0x05,0x05,0x05,0x05,
131 0x05,0x05,0x05,0x05,0x04,0x04,0x04,0x04,0x04,0x04,
132 0x04,0x04,0x04,0x04,0x04,0x03,0x03,0x03,0x03,0x03,
133 0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x02,
134 0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,
135 0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x01,0x01,
136 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
137 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
138 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
139 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
140 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
141 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
142 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
143 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
144 };
145 
146 const uint16_t ff_ac3_hearing_threshold_tab[AC3_CRITICAL_BANDS][3]= {
147 { 0x04d0,0x04f0,0x0580 },
148 { 0x04d0,0x04f0,0x0580 },
149 { 0x0440,0x0460,0x04b0 },
150 { 0x0400,0x0410,0x0450 },
151 { 0x03e0,0x03e0,0x0420 },
152 { 0x03c0,0x03d0,0x03f0 },
153 { 0x03b0,0x03c0,0x03e0 },
154 { 0x03b0,0x03b0,0x03d0 },
155 { 0x03a0,0x03b0,0x03c0 },
156 { 0x03a0,0x03a0,0x03b0 },
157 { 0x03a0,0x03a0,0x03b0 },
158 { 0x03a0,0x03a0,0x03b0 },
159 { 0x03a0,0x03a0,0x03a0 },
160 { 0x0390,0x03a0,0x03a0 },
161 { 0x0390,0x0390,0x03a0 },
162 { 0x0390,0x0390,0x03a0 },
163 { 0x0380,0x0390,0x03a0 },
164 { 0x0380,0x0380,0x03a0 },
165 { 0x0370,0x0380,0x03a0 },
166 { 0x0370,0x0380,0x03a0 },
167 { 0x0360,0x0370,0x0390 },
168 { 0x0360,0x0370,0x0390 },
169 { 0x0350,0x0360,0x0390 },
170 { 0x0350,0x0360,0x0390 },
171 { 0x0340,0x0350,0x0380 },
172 { 0x0340,0x0350,0x0380 },
173 { 0x0330,0x0340,0x0380 },
174 { 0x0320,0x0340,0x0370 },
175 { 0x0310,0x0320,0x0360 },
176 { 0x0300,0x0310,0x0350 },
177 { 0x02f0,0x0300,0x0340 },
178 { 0x02f0,0x02f0,0x0330 },
179 { 0x02f0,0x02f0,0x0320 },
180 { 0x02f0,0x02f0,0x0310 },
181 { 0x0300,0x02f0,0x0300 },
182 { 0x0310,0x0300,0x02f0 },
183 { 0x0340,0x0320,0x02f0 },
184 { 0x0390,0x0350,0x02f0 },
185 { 0x03e0,0x0390,0x0300 },
186 { 0x0420,0x03e0,0x0310 },
187 { 0x0460,0x0420,0x0330 },
188 { 0x0490,0x0450,0x0350 },
189 { 0x04a0,0x04a0,0x03c0 },
190 { 0x0460,0x0490,0x0410 },
191 { 0x0440,0x0460,0x0470 },
192 { 0x0440,0x0440,0x04a0 },
193 { 0x0520,0x0480,0x0460 },
194 { 0x0800,0x0630,0x0440 },
195 { 0x0840,0x0840,0x0450 },
196 { 0x0840,0x0840,0x04e0 },
197 };
198 
199 const uint8_t ff_ac3_bap_tab[64]= {
200  0, 1, 1, 1, 1, 1, 2, 2, 3, 3,
201  3, 4, 4, 5, 5, 6, 6, 6, 6, 7,
202  7, 7, 7, 8, 8, 8, 8, 9, 9, 9,
203  9, 10, 10, 10, 10, 11, 11, 11, 11, 12,
204  12, 12, 12, 13, 13, 13, 13, 14, 14, 14,
205  14, 14, 14, 14, 14, 15, 15, 15, 15, 15,
206  15, 15, 15, 15,
207 };
208 
209 const uint8_t ff_ac3_slow_decay_tab[4]={
210  0x0f, 0x11, 0x13, 0x15,
211 };
212 
213 const uint8_t ff_ac3_fast_decay_tab[4]={
214  0x3f, 0x53, 0x67, 0x7b,
215 };
216 
217 const uint16_t ff_ac3_slow_gain_tab[4]= {
218  0x540, 0x4d8, 0x478, 0x410,
219 };
220 
221 const uint16_t ff_ac3_db_per_bit_tab[4]= {
222  0x000, 0x700, 0x900, 0xb00,
223 };
224 
225 const int16_t ff_ac3_floor_tab[8]= {
226  0x2f0, 0x2b0, 0x270, 0x230, 0x1f0, 0x170, 0x0f0, 0xf800,
227 };
228 
229 const uint16_t ff_ac3_fast_gain_tab[8]= {
230  0x080, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400,
231 };
232 
233 const uint64_t ff_eac3_custom_channel_map_locations[16][2] = {
234  { 1, AV_CH_FRONT_LEFT },
235  { 1, AV_CH_FRONT_CENTER },
236  { 1, AV_CH_FRONT_RIGHT },
237  { 1, AV_CH_SIDE_LEFT },
238  { 1, AV_CH_SIDE_RIGHT },
239  { 0, AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER },
240  { 0, AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT },
241  { 0, AV_CH_BACK_CENTER },
242  { 0, AV_CH_TOP_CENTER },
243  { 0, AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT },
244  { 0, AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT },
245  { 0, AV_CH_TOP_FRONT_LEFT | AV_CH_TOP_FRONT_RIGHT},
246  { 0, AV_CH_TOP_FRONT_CENTER },
247  { 0, AV_CH_TOP_BACK_LEFT | AV_CH_TOP_BACK_RIGHT },
248  { 0, AV_CH_LOW_FREQUENCY_2 },
249  { 1, AV_CH_LOW_FREQUENCY },
250 };
ff_ac3_fast_decay_tab
const uint8_t ff_ac3_fast_decay_tab[4]
Definition: ac3tab.c:213
AV_CH_TOP_FRONT_CENTER
#define AV_CH_TOP_FRONT_CENTER
Definition: channel_layout.h:62
AV_CH_LOW_FREQUENCY_2
#define AV_CH_LOW_FREQUENCY_2
Definition: channel_layout.h:73
COMMON_CHANNEL_MAP
#define COMMON_CHANNEL_MAP
Definition: ac3tab.h:66
AV_CH_TOP_FRONT_RIGHT
#define AV_CH_TOP_FRONT_RIGHT
Definition: channel_layout.h:63
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:61
AC3_CRITICAL_BANDS
#define AC3_CRITICAL_BANDS
Definition: ac3.h:42
AV_CH_WIDE_LEFT
#define AV_CH_WIDE_LEFT
Definition: channel_layout.h:69
AV_CH_SURROUND_DIRECT_RIGHT
#define AV_CH_SURROUND_DIRECT_RIGHT
Definition: channel_layout.h:72
AV_CH_WIDE_RIGHT
#define AV_CH_WIDE_RIGHT
Definition: channel_layout.h:70
AV_CH_TOP_BACK_LEFT
#define AV_CH_TOP_BACK_LEFT
Definition: channel_layout.h:64
AV_CH_BACK_LEFT
#define AV_CH_BACK_LEFT
Definition: channel_layout.h:53
ff_ac3_bap_tab
const uint8_t ff_ac3_bap_tab[64]
Definition: ac3tab.c:199
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
ff_ac3_log_add_tab
const uint8_t ff_ac3_log_add_tab[260]
Definition: ac3tab.c:117
AV_CH_LOW_FREQUENCY
#define AV_CH_LOW_FREQUENCY
Definition: channel_layout.h:52
ff_ac3_floor_tab
const int16_t ff_ac3_floor_tab[8]
Definition: ac3tab.c:225
AV_CH_TOP_CENTER
#define AV_CH_TOP_CENTER
Definition: channel_layout.h:60
AV_CH_FRONT_CENTER
#define AV_CH_FRONT_CENTER
Definition: channel_layout.h:51
AV_CH_FRONT_LEFT_OF_CENTER
#define AV_CH_FRONT_LEFT_OF_CENTER
Definition: channel_layout.h:55
ff_eac3_custom_channel_map_locations
const uint64_t ff_eac3_custom_channel_map_locations[16][2]
Definition: ac3tab.c:233
ff_ac3_db_per_bit_tab
const uint16_t ff_ac3_db_per_bit_tab[4]
Definition: ac3tab.c:221
ff_ac3_hearing_threshold_tab
const uint16_t ff_ac3_hearing_threshold_tab[AC3_CRITICAL_BANDS][3]
Definition: ac3tab.c:146
AV_CH_TOP_BACK_RIGHT
#define AV_CH_TOP_BACK_RIGHT
Definition: channel_layout.h:66
AV_CH_FRONT_RIGHT_OF_CENTER
#define AV_CH_FRONT_RIGHT_OF_CENTER
Definition: channel_layout.h:56
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
ff_ac3_slow_decay_tab
const uint8_t ff_ac3_slow_decay_tab[4]
Definition: ac3tab.c:209
AV_CH_BACK_CENTER
#define AV_CH_BACK_CENTER
Definition: channel_layout.h:57
AV_CH_FRONT_LEFT
#define AV_CH_FRONT_LEFT
Definition: channel_layout.h:49
AV_CH_SIDE_RIGHT
#define AV_CH_SIDE_RIGHT
Definition: channel_layout.h:59
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
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:71
AV_CH_FRONT_RIGHT
#define AV_CH_FRONT_RIGHT
Definition: channel_layout.h:50
ff_ac3_slow_gain_tab
const uint16_t ff_ac3_slow_gain_tab[4]
Definition: ac3tab.c:217
ac3.h
ff_ac3_fast_gain_tab
const uint16_t ff_ac3_fast_gain_tab[8]
Definition: ac3tab.c:229
AV_CH_BACK_RIGHT
#define AV_CH_BACK_RIGHT
Definition: channel_layout.h:54
ac3tab.h
AV_CH_SIDE_LEFT
#define AV_CH_SIDE_LEFT
Definition: channel_layout.h:58
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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