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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 
28 #include "avcodec.h"
29 #include "ac3tab.h"
30 
31 /**
32  * Possible frame sizes.
33  * from ATSC A/52 Table 5.18 Frame Size Code Table.
34  */
35 const uint16_t ff_ac3_frame_size_tab[38][3] = {
36  { 64, 69, 96 },
37  { 64, 70, 96 },
38  { 80, 87, 120 },
39  { 80, 88, 120 },
40  { 96, 104, 144 },
41  { 96, 105, 144 },
42  { 112, 121, 168 },
43  { 112, 122, 168 },
44  { 128, 139, 192 },
45  { 128, 140, 192 },
46  { 160, 174, 240 },
47  { 160, 175, 240 },
48  { 192, 208, 288 },
49  { 192, 209, 288 },
50  { 224, 243, 336 },
51  { 224, 244, 336 },
52  { 256, 278, 384 },
53  { 256, 279, 384 },
54  { 320, 348, 480 },
55  { 320, 349, 480 },
56  { 384, 417, 576 },
57  { 384, 418, 576 },
58  { 448, 487, 672 },
59  { 448, 488, 672 },
60  { 512, 557, 768 },
61  { 512, 558, 768 },
62  { 640, 696, 960 },
63  { 640, 697, 960 },
64  { 768, 835, 1152 },
65  { 768, 836, 1152 },
66  { 896, 975, 1344 },
67  { 896, 976, 1344 },
68  { 1024, 1114, 1536 },
69  { 1024, 1115, 1536 },
70  { 1152, 1253, 1728 },
71  { 1152, 1254, 1728 },
72  { 1280, 1393, 1920 },
73  { 1280, 1394, 1920 },
74 };
75 
76 /**
77  * Map audio coding mode (acmod) to number of full-bandwidth channels.
78  * from ATSC A/52 Table 5.8 Audio Coding Mode
79  */
81  2, 1, 2, 3, 3, 4, 4, 5
82 };
83 
84 /**
85  * Map audio coding mode (acmod) to channel layout mask.
86  */
87 const uint16_t avpriv_ac3_channel_layout_tab[8] = {
96 };
97 
98 #define COMMON_CHANNEL_MAP \
99  { { 0, 1, }, { 0, 1, 2, } },\
100  { { 0, }, { 0, 1, } },\
101  { { 0, 1, }, { 0, 1, 2, } },\
102  { { 0, 2, 1, }, { 0, 2, 1, 3, } },\
103  { { 0, 1, 2, }, { 0, 1, 3, 2, } },\
104  { { 0, 2, 1, 3, }, { 0, 2, 1, 4, 3, } },
105 
106 /**
107  * Table to remap channels from SMPTE order to AC-3 order.
108  * [channel_mode][lfe][ch]
109  */
110 const uint8_t ff_ac3_enc_channel_map[8][2][6] = {
112  { { 0, 1, 2, 3, }, { 0, 1, 3, 4, 2, } },
113  { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 4, 5, 3 } },
114 };
115 
116 /**
117  * Table to remap channels from from AC-3 order to SMPTE order.
118  * [channel_mode][lfe][ch]
119  */
120 const uint8_t ff_ac3_dec_channel_map[8][2][6] = {
122  { { 0, 1, 2, 3, }, { 0, 1, 4, 2, 3, } },
123  { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 5, 3, 4 } },
124 };
125 
126 /* possible frequencies */
127 const uint16_t ff_ac3_sample_rate_tab[3] = { 48000, 44100, 32000 };
128 
129 /* possible bitrates */
130 const uint16_t ff_ac3_bitrate_tab[19] = {
131  32, 40, 48, 56, 64, 80, 96, 112, 128,
132  160, 192, 224, 256, 320, 384, 448, 512, 576, 640
133 };
134 
135 /**
136  * Table of bin locations for rematrixing bands
137  * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
138  */
139 const uint8_t ff_ac3_rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };
140 
141 /**
142  * Table E2.16 Default Coupling Banding Structure
143  */
145  0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1
146 };
147 
148 /* AC-3 MDCT window */
149 
150 /* MDCT window */
152  4, 7, 12, 16, 21, 28, 34, 42,
153  51, 61, 72, 84, 97, 111, 127, 145,
154  164, 184, 207, 231, 257, 285, 315, 347,
155  382, 419, 458, 500, 544, 591, 641, 694,
156  750, 810, 872, 937, 1007, 1079, 1155, 1235,
157  1318, 1406, 1497, 1593, 1692, 1796, 1903, 2016,
158  2132, 2253, 2379, 2509, 2644, 2783, 2927, 3076,
159  3230, 3389, 3552, 3721, 3894, 4072, 4255, 4444,
160  4637, 4835, 5038, 5246, 5459, 5677, 5899, 6127,
161  6359, 6596, 6837, 7083, 7334, 7589, 7848, 8112,
162  8380, 8652, 8927, 9207, 9491, 9778,10069,10363,
163 10660,10960,11264,11570,11879,12190,12504,12820,
164 13138,13458,13780,14103,14427,14753,15079,15407,
165 15735,16063,16392,16720,17049,17377,17705,18032,
166 18358,18683,19007,19330,19651,19970,20287,20602,
167 20914,21225,21532,21837,22139,22438,22733,23025,
168 23314,23599,23880,24157,24430,24699,24964,25225,
169 25481,25732,25979,26221,26459,26691,26919,27142,
170 27359,27572,27780,27983,28180,28373,28560,28742,
171 28919,29091,29258,29420,29577,29729,29876,30018,
172 30155,30288,30415,30538,30657,30771,30880,30985,
173 31086,31182,31274,31363,31447,31528,31605,31678,
174 31747,31814,31877,31936,31993,32046,32097,32145,
175 32190,32232,32272,32310,32345,32378,32409,32438,
176 32465,32490,32513,32535,32556,32574,32592,32608,
177 32623,32636,32649,32661,32671,32681,32690,32698,
178 32705,32712,32718,32724,32729,32733,32737,32741,
179 32744,32747,32750,32752,32754,32756,32757,32759,
180 32760,32761,32762,32763,32764,32764,32765,32765,
181 32766,32766,32766,32766,32767,32767,32767,32767,
182 32767,32767,32767,32767,32767,32767,32767,32767,
183 32767,32767,32767,32767,32767,32767,32767,32767,
184 };
185 
187 0x40,0x3f,0x3e,0x3d,0x3c,0x3b,0x3a,0x39,0x38,0x37,
188 0x36,0x35,0x34,0x34,0x33,0x32,0x31,0x30,0x2f,0x2f,
189 0x2e,0x2d,0x2c,0x2c,0x2b,0x2a,0x29,0x29,0x28,0x27,
190 0x26,0x26,0x25,0x24,0x24,0x23,0x23,0x22,0x21,0x21,
191 0x20,0x20,0x1f,0x1e,0x1e,0x1d,0x1d,0x1c,0x1c,0x1b,
192 0x1b,0x1a,0x1a,0x19,0x19,0x18,0x18,0x17,0x17,0x16,
193 0x16,0x15,0x15,0x15,0x14,0x14,0x13,0x13,0x13,0x12,
194 0x12,0x12,0x11,0x11,0x11,0x10,0x10,0x10,0x0f,0x0f,
195 0x0f,0x0e,0x0e,0x0e,0x0d,0x0d,0x0d,0x0d,0x0c,0x0c,
196 0x0c,0x0c,0x0b,0x0b,0x0b,0x0b,0x0a,0x0a,0x0a,0x0a,
197 0x0a,0x09,0x09,0x09,0x09,0x09,0x08,0x08,0x08,0x08,
198 0x08,0x08,0x07,0x07,0x07,0x07,0x07,0x07,0x06,0x06,
199 0x06,0x06,0x06,0x06,0x06,0x06,0x05,0x05,0x05,0x05,
200 0x05,0x05,0x05,0x05,0x04,0x04,0x04,0x04,0x04,0x04,
201 0x04,0x04,0x04,0x04,0x04,0x03,0x03,0x03,0x03,0x03,
202 0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x02,
203 0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,
204 0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x02,0x01,0x01,
205 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
206 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
207 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,
208 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
209 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
210 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
211 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
212 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
213 };
214 
216 { 0x04d0,0x04f0,0x0580 },
217 { 0x04d0,0x04f0,0x0580 },
218 { 0x0440,0x0460,0x04b0 },
219 { 0x0400,0x0410,0x0450 },
220 { 0x03e0,0x03e0,0x0420 },
221 { 0x03c0,0x03d0,0x03f0 },
222 { 0x03b0,0x03c0,0x03e0 },
223 { 0x03b0,0x03b0,0x03d0 },
224 { 0x03a0,0x03b0,0x03c0 },
225 { 0x03a0,0x03a0,0x03b0 },
226 { 0x03a0,0x03a0,0x03b0 },
227 { 0x03a0,0x03a0,0x03b0 },
228 { 0x03a0,0x03a0,0x03a0 },
229 { 0x0390,0x03a0,0x03a0 },
230 { 0x0390,0x0390,0x03a0 },
231 { 0x0390,0x0390,0x03a0 },
232 { 0x0380,0x0390,0x03a0 },
233 { 0x0380,0x0380,0x03a0 },
234 { 0x0370,0x0380,0x03a0 },
235 { 0x0370,0x0380,0x03a0 },
236 { 0x0360,0x0370,0x0390 },
237 { 0x0360,0x0370,0x0390 },
238 { 0x0350,0x0360,0x0390 },
239 { 0x0350,0x0360,0x0390 },
240 { 0x0340,0x0350,0x0380 },
241 { 0x0340,0x0350,0x0380 },
242 { 0x0330,0x0340,0x0380 },
243 { 0x0320,0x0340,0x0370 },
244 { 0x0310,0x0320,0x0360 },
245 { 0x0300,0x0310,0x0350 },
246 { 0x02f0,0x0300,0x0340 },
247 { 0x02f0,0x02f0,0x0330 },
248 { 0x02f0,0x02f0,0x0320 },
249 { 0x02f0,0x02f0,0x0310 },
250 { 0x0300,0x02f0,0x0300 },
251 { 0x0310,0x0300,0x02f0 },
252 { 0x0340,0x0320,0x02f0 },
253 { 0x0390,0x0350,0x02f0 },
254 { 0x03e0,0x0390,0x0300 },
255 { 0x0420,0x03e0,0x0310 },
256 { 0x0460,0x0420,0x0330 },
257 { 0x0490,0x0450,0x0350 },
258 { 0x04a0,0x04a0,0x03c0 },
259 { 0x0460,0x0490,0x0410 },
260 { 0x0440,0x0460,0x0470 },
261 { 0x0440,0x0440,0x04a0 },
262 { 0x0520,0x0480,0x0460 },
263 { 0x0800,0x0630,0x0440 },
264 { 0x0840,0x0840,0x0450 },
265 { 0x0840,0x0840,0x04e0 },
266 };
267 
269  0, 1, 1, 1, 1, 1, 2, 2, 3, 3,
270  3, 4, 4, 5, 5, 6, 6, 6, 6, 7,
271  7, 7, 7, 8, 8, 8, 8, 9, 9, 9,
272  9, 10, 10, 10, 10, 11, 11, 11, 11, 12,
273  12, 12, 12, 13, 13, 13, 13, 14, 14, 14,
274  14, 14, 14, 14, 14, 15, 15, 15, 15, 15,
275  15, 15, 15, 15,
276 };
277 
279  0x0f, 0x11, 0x13, 0x15,
280 };
281 
283  0x3f, 0x53, 0x67, 0x7b,
284 };
285 
286 const uint16_t ff_ac3_slow_gain_tab[4]= {
287  0x540, 0x4d8, 0x478, 0x410,
288 };
289 
290 const uint16_t ff_ac3_db_per_bit_tab[4]= {
291  0x000, 0x700, 0x900, 0xb00,
292 };
293 
294 const int16_t ff_ac3_floor_tab[8]= {
295  0x2f0, 0x2b0, 0x270, 0x230, 0x1f0, 0x170, 0x0f0, 0xf800,
296 };
297 
298 const uint16_t ff_ac3_fast_gain_tab[8]= {
299  0x080, 0x100, 0x180, 0x200, 0x280, 0x300, 0x380, 0x400,
300 };
301 
302 /**
303  * Default channel map for a dependent substream defined by acmod
304  */
305 const uint16_t ff_eac3_default_chmap[8] = {
306  AC3_CHMAP_L | AC3_CHMAP_R, // FIXME Ch1+Ch2
307  AC3_CHMAP_C,
309  AC3_CHMAP_L | AC3_CHMAP_C | AC3_CHMAP_R,
311  AC3_CHMAP_L | AC3_CHMAP_C | AC3_CHMAP_R | AC3_CHMAP_C_SUR,
314 };