ffmpeg/libavcodec/bgmc.c

571 lines
29 KiB
C

/*
* Block Gilbert-Moore decoder
* Copyright (c) 2010 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Block Gilbert-Moore decoder as used by MPEG-4 ALS
* @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
*/
#include "bgmc.h"
#define FREQ_BITS 14 // bits used by frequency counters
#define VALUE_BITS 18 // bits used to represent the values
#define TOP_VALUE ((1 << VALUE_BITS) - 1) // maximum value
#define FIRST_QTR (TOP_VALUE / 4 + 1) // first quarter of values maximum value
#define HALF (2 * FIRST_QTR) // first half of values maximum value
#define THIRD_QTR (3 * FIRST_QTR) // third quarter of values maximum value
#define LUT_BITS (FREQ_BITS - 8) // number of bits used to index lookup tables
#define LUT_SIZE (1 << LUT_BITS) // size of the lookup tables
#define LUT_BUFF 4 // number of buffered lookup tables
/** Cumulative frequency tables for block Gilbert-Moore coding.
*/
static const uint16_t cf_tables_1[3][129] = {
{
16384, 16066, 15748, 15431, 15114, 14799, 14485, 14173, 13861, 13552,
13243, 12939, 12635, 12336, 12038, 11745, 11452, 11161, 10870, 10586,
10303, 10027, 9751, 9483, 9215, 8953, 8692, 8440, 8189, 7946,
7704, 7472, 7240, 7008, 6776, 6554, 6333, 6122, 5912, 5711,
5512, 5320, 5128, 4947, 4766, 4595, 4425, 4264, 4104, 3946,
3788, 3640, 3493, 3355, 3218, 3090, 2963, 2842, 2721, 2609,
2498, 2395, 2292, 2196, 2100, 2004, 1908, 1820, 1732, 1651,
1570, 1497, 1424, 1355, 1287, 1223, 1161, 1100, 1044, 988,
938, 888, 839, 790, 746, 702, 662, 623, 588, 553,
520, 488, 459, 431, 405, 380, 357, 334, 311, 288,
268, 248, 230, 213, 197, 182, 168, 154, 142, 130,
119, 108, 99, 90, 81, 72, 64, 56, 49, 42,
36, 30, 25, 20, 15, 11, 7, 3, 0
},
{
16384, 16080, 15776, 15473, 15170, 14868, 14567, 14268, 13970, 13674,
13378, 13086, 12794, 12505, 12218, 11936, 11654, 11373, 11092, 10818,
10544, 10276, 10008, 9749, 9490, 9236, 8982, 8737, 8492, 8256,
8020, 7792, 7564, 7336, 7108, 6888, 6669, 6459, 6249, 6050,
5852, 5660, 5468, 5286, 5104, 4931, 4760, 4598, 4436, 4275,
4115, 3965, 3816, 3674, 3534, 3403, 3272, 3147, 3023, 2907,
2792, 2684, 2577, 2476, 2375, 2274, 2173, 2079, 1986, 1897,
1810, 1724, 1645, 1567, 1493, 1419, 1351, 1284, 1222, 1161,
1105, 1050, 995, 941, 891, 842, 797, 753, 713, 673,
636, 599, 566, 533, 503, 473, 446, 419, 392, 365,
340, 316, 294, 272, 253, 234, 216, 199, 184, 169,
155, 142, 130, 118, 106, 95, 85, 75, 66, 57,
49, 41, 34, 27, 21, 15, 10, 5, 0
},
{
16384, 16092, 15801, 15510, 15219, 14930, 14641, 14355, 14069, 13785,
13501, 13219, 12938, 12661, 12384, 12112, 11841, 11571, 11301, 11037,
10773, 10514, 10256, 10005, 9754, 9508, 9263, 9025, 8787, 8557,
8327, 8103, 7879, 7655, 7431, 7215, 7000, 6792, 6585, 6387,
6190, 5998, 5807, 5625, 5445, 5272, 5100, 4937, 4774, 4613,
4452, 4301, 4150, 4007, 3865, 3731, 3597, 3469, 3341, 3218,
3099, 2981, 2869, 2758, 2652, 2546, 2440, 2334, 2234, 2134,
2041, 1949, 1864, 1779, 1699, 1620, 1547, 1474, 1407, 1340,
1278, 1217, 1157, 1097, 1043, 989, 940, 891, 846, 801,
759, 718, 680, 643, 609, 575, 543, 511, 479, 447,
418, 389, 363, 337, 314, 291, 270, 249, 230, 212,
195, 179, 164, 149, 135, 121, 108, 96, 85, 74,
64, 54, 45, 36, 28, 20, 13, 6, 0
}
};
static const uint16_t cf_tables_2[8][193] = {
{
16384, 16104, 15825, 15546, 15268, 14991, 14714, 14439, 14164, 13891,
13620, 13350, 13081, 12815, 12549, 12287, 12025, 11765, 11505, 11250,
10996, 10746, 10497, 10254, 10011, 9772, 9534, 9303, 9072, 8848,
8624, 8406, 8188, 7970, 7752, 7539, 7327, 7123, 6919, 6724,
6529, 6339, 6150, 5970, 5790, 5618, 5446, 5282, 5119, 4957,
4795, 4642, 4490, 4345, 4201, 4065, 3929, 3798, 3669, 3547,
3425, 3310, 3196, 3086, 2976, 2866, 2756, 2650, 2545, 2447,
2350, 2260, 2170, 2085, 2000, 1921, 1843, 1770, 1698, 1632,
1566, 1501, 1436, 1376, 1316, 1261, 1207, 1157, 1108, 1061,
1015, 973, 931, 893, 855, 819, 783, 747, 711, 677,
644, 614, 584, 557, 530, 505, 480, 458, 436, 416,
396, 378, 360, 343, 326, 310, 295, 281, 267, 255,
243, 232, 221, 211, 201, 192, 183, 174, 166, 158,
150, 142, 134, 126, 119, 112, 106, 100, 95, 90,
85, 80, 76, 72, 69, 66, 63, 60, 57, 54,
51, 48, 46, 44, 42, 40, 38, 36, 34, 33,
32, 31, 30, 29, 28, 27, 26, 25, 24, 23,
22, 21, 20, 19, 18, 17, 16, 15, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4, 3,
2, 1, 0
},
{
16384, 16116, 15849, 15582, 15316, 15050, 14785, 14521, 14257, 13995,
13734, 13476, 13218, 12963, 12708, 12457, 12206, 11956, 11706, 11460,
11215, 10975, 10735, 10500, 10265, 10034, 9803, 9579, 9355, 9136,
8917, 8703, 8489, 8275, 8061, 7853, 7645, 7444, 7244, 7051,
6858, 6671, 6484, 6305, 6127, 5956, 5785, 5622, 5459, 5298,
5137, 4983, 4830, 4684, 4539, 4401, 4263, 4131, 3999, 3874,
3750, 3632, 3515, 3401, 3287, 3173, 3059, 2949, 2840, 2737,
2635, 2539, 2444, 2354, 2264, 2181, 2098, 2020, 1943, 1872,
1801, 1731, 1661, 1596, 1532, 1472, 1412, 1357, 1303, 1251,
1200, 1153, 1106, 1063, 1020, 979, 938, 897, 856, 818,
780, 746, 712, 681, 650, 621, 592, 566, 540, 517,
494, 473, 452, 431, 410, 391, 373, 356, 340, 325,
310, 296, 282, 270, 258, 247, 236, 225, 214, 203,
192, 182, 172, 162, 153, 144, 136, 128, 121, 114,
108, 102, 97, 92, 87, 82, 77, 73, 69, 65,
62, 59, 56, 53, 50, 47, 45, 43, 41, 39,
37, 35, 33, 31, 29, 27, 26, 25, 24, 23,
22, 21, 20, 19, 18, 17, 16, 15, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4, 3,
2, 1, 0
},
{
16384, 16128, 15872, 15617, 15362, 15107, 14853, 14600, 14347, 14096,
13846, 13597, 13350, 13105, 12860, 12618, 12376, 12135, 11894, 11657,
11421, 11189, 10957, 10730, 10503, 10279, 10056, 9838, 9620, 9407,
9195, 8987, 8779, 8571, 8363, 8159, 7955, 7758, 7561, 7371,
7182, 6997, 6812, 6635, 6459, 6289, 6120, 5957, 5795, 5634,
5473, 5319, 5165, 5018, 4871, 4732, 4593, 4458, 4324, 4197,
4071, 3951, 3831, 3714, 3597, 3480, 3363, 3250, 3138, 3032,
2927, 2828, 2729, 2635, 2541, 2453, 2366, 2284, 2202, 2126,
2050, 1975, 1900, 1830, 1761, 1697, 1633, 1574, 1515, 1459,
1403, 1351, 1300, 1252, 1205, 1160, 1115, 1070, 1025, 982,
939, 899, 860, 824, 789, 756, 723, 693, 663, 636,
609, 584, 559, 535, 511, 489, 467, 447, 427, 409,
391, 374, 358, 343, 328, 313, 300, 287, 274, 261,
248, 235, 223, 211, 200, 189, 179, 169, 160, 151,
143, 135, 128, 121, 115, 109, 103, 97, 92, 87,
82, 77, 73, 69, 65, 61, 58, 55, 52, 49,
46, 43, 40, 37, 35, 33, 31, 29, 27, 25,
23, 21, 20, 19, 18, 17, 16, 15, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4, 3,
2, 1, 0
},
{
16384, 16139, 15894, 15649, 15405, 15162, 14919, 14677, 14435, 14195,
13955, 13717, 13479, 13243, 13008, 12775, 12542, 12310, 12079, 11851,
11623, 11399, 11176, 10956, 10737, 10521, 10305, 10094, 9883, 9677,
9471, 9268, 9065, 8862, 8659, 8459, 8260, 8067, 7874, 7688,
7502, 7321, 7140, 6965, 6790, 6621, 6452, 6290, 6128, 5968,
5808, 5655, 5503, 5356, 5209, 5069, 4929, 4794, 4660, 4532,
4404, 4282, 4160, 4041, 3922, 3803, 3684, 3568, 3452, 3343,
3234, 3131, 3029, 2931, 2833, 2741, 2649, 2563, 2477, 2396,
2316, 2236, 2157, 2083, 2009, 1940, 1871, 1807, 1743, 1683,
1623, 1567, 1511, 1459, 1407, 1357, 1307, 1257, 1207, 1159,
1111, 1067, 1023, 983, 943, 905, 868, 834, 800, 769,
738, 709, 681, 653, 625, 600, 575, 552, 529, 508,
487, 466, 447, 428, 410, 392, 376, 360, 344, 328,
313, 298, 283, 268, 255, 242, 230, 218, 207, 196,
186, 176, 167, 158, 150, 142, 135, 128, 121, 114,
108, 102, 97, 92, 87, 82, 78, 74, 70, 66,
62, 58, 54, 50, 47, 44, 41, 38, 35, 32,
30, 28, 26, 24, 22, 20, 18, 16, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4, 3,
2, 1, 0
},
{
16384, 16149, 15915, 15681, 15447, 15214, 14981, 14749, 14517, 14286,
14055, 13827, 13599, 13373, 13147, 12923, 12699, 12476, 12253, 12034,
11815, 11599, 11383, 11171, 10959, 10750, 10541, 10337, 10133, 9933,
9733, 9536, 9339, 9142, 8945, 8751, 8557, 8369, 8181, 7998,
7816, 7638, 7460, 7288, 7116, 6950, 6785, 6625, 6465, 6306,
6147, 5995, 5843, 5697, 5551, 5411, 5271, 5135, 5000, 4871,
4742, 4618, 4495, 4374, 4253, 4132, 4011, 3893, 3775, 3663,
3552, 3446, 3340, 3239, 3138, 3043, 2948, 2858, 2768, 2684,
2600, 2516, 2433, 2355, 2278, 2205, 2133, 2065, 1997, 1932,
1867, 1807, 1747, 1690, 1634, 1580, 1526, 1472, 1418, 1366,
1314, 1266, 1218, 1174, 1130, 1088, 1047, 1009, 971, 936,
901, 868, 836, 804, 772, 743, 714, 685, 658, 631,
606, 582, 559, 536, 515, 494, 475, 456, 437, 418,
399, 380, 362, 344, 328, 312, 297, 283, 270, 257,
245, 233, 222, 211, 201, 191, 181, 172, 163, 155,
147, 139, 132, 125, 119, 113, 107, 101, 96, 91,
86, 81, 76, 71, 66, 62, 58, 54, 50, 46,
43, 40, 37, 34, 31, 28, 26, 24, 22, 20,
18, 16, 14, 12, 10, 8, 6, 5, 4, 3,
2, 1, 0
},
{
16384, 16159, 15934, 15709, 15485, 15261, 15038, 14816, 14594, 14373,
14152, 13933, 13714, 13497, 13280, 13065, 12850, 12636, 12422, 12211,
12000, 11791, 11583, 11378, 11173, 10971, 10769, 10571, 10373, 10179,
9985, 9793, 9601, 9409, 9217, 9029, 8842, 8658, 8475, 8297,
8120, 7946, 7773, 7604, 7435, 7271, 7108, 6950, 6792, 6634,
6477, 6326, 6175, 6029, 5883, 5742, 5602, 5466, 5330, 5199,
5068, 4943, 4818, 4696, 4574, 4452, 4330, 4211, 4093, 3979,
3866, 3759, 3652, 3549, 3446, 3348, 3250, 3157, 3065, 2977,
2889, 2802, 2716, 2634, 2553, 2476, 2399, 2326, 2254, 2185,
2117, 2052, 1987, 1926, 1866, 1808, 1750, 1692, 1634, 1578,
1522, 1470, 1418, 1369, 1321, 1275, 1229, 1187, 1145, 1105,
1066, 1027, 991, 955, 919, 883, 850, 817, 786, 756,
728, 700, 674, 648, 624, 600, 578, 556, 534, 512,
490, 468, 447, 426, 407, 388, 371, 354, 338, 322,
307, 293, 280, 267, 255, 243, 231, 219, 209, 199,
189, 179, 170, 161, 153, 145, 138, 131, 124, 117,
111, 105, 99, 93, 87, 81, 76, 71, 66, 61,
57, 53, 49, 45, 42, 39, 36, 33, 30, 27,
24, 21, 19, 17, 15, 13, 11, 9, 7, 5,
3, 1, 0
},
{
16384, 16169, 15954, 15739, 15524, 15310, 15096, 14883, 14670, 14458,
14246, 14035, 13824, 13614, 13405, 13198, 12991, 12785, 12579, 12376,
12173, 11972, 11772, 11574, 11377, 11182, 10987, 10795, 10603, 10414,
10226, 10040, 9854, 9668, 9482, 9299, 9116, 8937, 8759, 8585,
8411, 8241, 8071, 7906, 7741, 7580, 7419, 7263, 7107, 6952,
6797, 6647, 6497, 6353, 6209, 6070, 5931, 5796, 5661, 5531,
5401, 5275, 5150, 5027, 4904, 4781, 4658, 4538, 4419, 4304,
4190, 4081, 3972, 3867, 3762, 3662, 3562, 3467, 3372, 3281,
3191, 3101, 3012, 2928, 2844, 2764, 2684, 2608, 2533, 2460,
2387, 2318, 2250, 2185, 2121, 2059, 1997, 1935, 1873, 1813,
1754, 1698, 1642, 1588, 1535, 1483, 1433, 1384, 1338, 1292,
1249, 1206, 1165, 1125, 1085, 1045, 1008, 971, 937, 903,
871, 840, 810, 780, 752, 724, 698, 672, 647, 622,
597, 572, 548, 524, 502, 480, 460, 440, 421, 403,
386, 369, 353, 337, 323, 309, 295, 281, 268, 255,
243, 231, 220, 209, 199, 189, 180, 171, 163, 155,
147, 139, 131, 123, 116, 109, 102, 95, 89, 83,
77, 72, 67, 62, 57, 52, 48, 44, 40, 36,
32, 28, 25, 22, 19, 16, 13, 10, 8, 6,
4, 2, 0
},
{
16384, 16177, 15970, 15764, 15558, 15353, 15148, 14944, 14740, 14537,
14334, 14132, 13930, 13729, 13529, 13330, 13131, 12933, 12735, 12539,
12343, 12150, 11957, 11766, 11576, 11388, 11200, 11015, 10830, 10647,
10465, 10285, 10105, 9925, 9745, 9568, 9391, 9218, 9045, 8876,
8707, 8541, 8375, 8213, 8051, 7894, 7737, 7583, 7429, 7277,
7125, 6977, 6830, 6687, 6544, 6406, 6268, 6133, 5998, 5868,
5738, 5612, 5487, 5364, 5241, 5118, 4995, 4875, 4755, 4640,
4525, 4414, 4304, 4198, 4092, 3990, 3888, 3790, 3693, 3600,
3507, 3415, 3323, 3235, 3147, 3064, 2981, 2902, 2823, 2746,
2670, 2594, 2522, 2450, 2382, 2314, 2248, 2182, 2116, 2050,
1987, 1924, 1864, 1804, 1748, 1692, 1638, 1585, 1534, 1484,
1437, 1390, 1346, 1302, 1258, 1215, 1174, 1133, 1095, 1057,
1021, 986, 952, 918, 887, 856, 827, 798, 770, 742,
714, 686, 659, 632, 607, 582, 559, 536, 514, 492,
472, 452, 433, 415, 398, 381, 364, 348, 333, 318,
304, 290, 277, 264, 252, 240, 229, 218, 208, 198,
188, 178, 168, 158, 149, 140, 132, 124, 116, 108,
101, 94, 87, 81, 75, 69, 64, 59, 54, 49,
44, 39, 35, 31, 27, 23, 19, 15, 12, 9,
6, 3, 0
}
};
static const uint16_t cf_tables_3[5][257] = {
{
16384, 16187, 15990, 15793, 15597, 15401, 15205, 15009, 14813, 14618,
14423, 14230, 14037, 13845, 13653, 13463, 13273, 13083, 12894, 12706,
12518, 12332, 12146, 11962, 11778, 11597, 11416, 11237, 11059, 10882,
10706, 10532, 10358, 10184, 10010, 9838, 9666, 9497, 9328, 9163,
8999, 8837, 8675, 8517, 8359, 8205, 8051, 7901, 7751, 7602,
7453, 7308, 7163, 7022, 6882, 6745, 6609, 6476, 6343, 6214,
6085, 5960, 5835, 5712, 5589, 5466, 5343, 5223, 5103, 4987,
4872, 4761, 4650, 4542, 4435, 4332, 4229, 4130, 4031, 3936,
3841, 3747, 3653, 3563, 3473, 3387, 3302, 3220, 3138, 3059,
2980, 2905, 2830, 2759, 2688, 2619, 2550, 2481, 2412, 2345,
2278, 2215, 2152, 2092, 2032, 1974, 1917, 1863, 1809, 1758,
1707, 1659, 1611, 1564, 1517, 1473, 1429, 1387, 1346, 1307,
1268, 1230, 1193, 1158, 1123, 1090, 1058, 1026, 994, 962,
930, 899, 869, 841, 813, 786, 760, 735, 710, 687,
664, 643, 622, 602, 582, 562, 543, 525, 507, 490,
473, 457, 442, 427, 412, 398, 385, 373, 361, 349,
337, 325, 313, 301, 290, 279, 269, 259, 249, 240,
231, 222, 214, 206, 199, 192, 185, 178, 171, 165,
159, 153, 148, 143, 138, 133, 128, 123, 119, 115,
111, 107, 103, 99, 95, 91, 87, 83, 80, 77,
74, 71, 68, 65, 63, 61, 59, 57, 55, 53,
51, 49, 47, 45, 43, 41, 40, 39, 38, 37,
36, 35, 34, 33, 32, 31, 30, 29, 28, 27,
26, 25, 24, 23, 22, 21, 20, 19, 18, 17,
16, 15, 14, 13, 12, 11, 10, 9, 8, 7,
6, 5, 4, 3, 2, 1, 0
},
{
16384, 16195, 16006, 15817, 15629, 15441, 15253, 15065, 14878, 14692,
14506, 14321, 14136, 13952, 13768, 13585, 13402, 13219, 13037, 12857,
12677, 12499, 12321, 12144, 11967, 11792, 11617, 11444, 11271, 11100,
10930, 10762, 10594, 10426, 10258, 10091, 9925, 9761, 9598, 9438,
9278, 9120, 8963, 8809, 8655, 8504, 8354, 8207, 8060, 7914,
7769, 7627, 7485, 7347, 7209, 7074, 6939, 6807, 6676, 6548,
6420, 6296, 6172, 6050, 5928, 5806, 5684, 5564, 5444, 5328,
5212, 5100, 4988, 4879, 4771, 4667, 4563, 4462, 4362, 4265,
4169, 4073, 3978, 3886, 3795, 3707, 3619, 3535, 3451, 3369,
3288, 3210, 3133, 3059, 2985, 2913, 2841, 2769, 2697, 2627,
2557, 2490, 2424, 2360, 2297, 2237, 2177, 2119, 2062, 2007,
1953, 1901, 1849, 1798, 1748, 1700, 1652, 1607, 1562, 1519,
1476, 1435, 1394, 1355, 1317, 1281, 1245, 1210, 1175, 1140,
1105, 1071, 1037, 1005, 973, 943, 913, 885, 857, 830,
804, 779, 754, 731, 708, 685, 663, 642, 621, 601,
581, 563, 545, 528, 511, 495, 479, 463, 448, 433,
419, 405, 391, 377, 364, 351, 338, 326, 314, 302,
291, 280, 270, 260, 251, 242, 234, 226, 218, 210,
202, 195, 188, 181, 174, 168, 162, 156, 150, 144,
139, 134, 129, 124, 119, 114, 109, 104, 100, 96,
92, 88, 84, 80, 77, 74, 71, 68, 65, 62,
59, 56, 54, 52, 50, 48, 46, 44, 42, 40,
38, 36, 34, 33, 32, 31, 30, 29, 28, 27,
26, 25, 24, 23, 22, 21, 20, 19, 18, 17,
16, 15, 14, 13, 12, 11, 10, 9, 8, 7,
6, 5, 4, 3, 2, 1, 0
},
{
16384, 16203, 16022, 15842, 15662, 15482, 15302, 15122, 14942, 14763,
14584, 14406, 14228, 14051, 13874, 13698, 13522, 13347, 13172, 12998,
12824, 12652, 12480, 12310, 12140, 11971, 11803, 11637, 11471, 11307,
11143, 10980, 10817, 10654, 10491, 10330, 10169, 10011, 9853, 9697,
9542, 9389, 9236, 9086, 8936, 8789, 8642, 8498, 8355, 8212,
8070, 7931, 7792, 7656, 7520, 7388, 7256, 7126, 6996, 6870,
6744, 6621, 6498, 6377, 6256, 6135, 6014, 5895, 5776, 5660,
5545, 5433, 5321, 5212, 5104, 4999, 4895, 4793, 4692, 4594,
4496, 4400, 4304, 4211, 4118, 4028, 3939, 3853, 3767, 3684,
3601, 3521, 3441, 3364, 3287, 3212, 3137, 3062, 2987, 2915,
2843, 2773, 2704, 2638, 2572, 2508, 2445, 2384, 2324, 2266,
2208, 2153, 2098, 2044, 1990, 1939, 1888, 1839, 1791, 1745,
1699, 1655, 1611, 1569, 1527, 1487, 1448, 1409, 1370, 1331,
1292, 1255, 1218, 1183, 1148, 1115, 1082, 1051, 1020, 990,
960, 932, 904, 878, 852, 826, 801, 777, 753, 731,
709, 687, 666, 645, 625, 605, 586, 567, 550, 533,
516, 499, 482, 465, 449, 433, 418, 403, 389, 375,
362, 349, 337, 325, 314, 303, 293, 283, 273, 263,
254, 245, 236, 227, 219, 211, 204, 197, 190, 183,
177, 171, 165, 159, 153, 147, 141, 135, 130, 125,
120, 115, 110, 105, 101, 97, 93, 89, 85, 81,
77, 74, 71, 68, 65, 62, 59, 56, 53, 51,
49, 47, 45, 43, 41, 39, 37, 35, 33, 31,
29, 27, 25, 23, 22, 21, 20, 19, 18, 17,
16, 15, 14, 13, 12, 11, 10, 9, 8, 7,
6, 5, 4, 3, 2, 1, 0
},
{
16384, 16210, 16036, 15863, 15690, 15517, 15344, 15172, 15000, 14828,
14656, 14485, 14314, 14145, 13976, 13808, 13640, 13472, 13304, 13137,
12970, 12804, 12639, 12475, 12312, 12149, 11987, 11827, 11667, 11508,
11349, 11192, 11035, 10878, 10721, 10565, 10410, 10257, 10104, 9953,
9802, 9654, 9506, 9359, 9213, 9070, 8927, 8787, 8647, 8508,
8369, 8233, 8097, 7964, 7831, 7700, 7570, 7442, 7315, 7190,
7065, 6943, 6821, 6701, 6581, 6461, 6341, 6223, 6105, 5990,
5876, 5764, 5653, 5545, 5437, 5331, 5226, 5124, 5022, 4924,
4826, 4729, 4632, 4538, 4444, 4353, 4262, 4174, 4087, 4002,
3917, 3835, 3753, 3674, 3595, 3518, 3441, 3364, 3287, 3212,
3138, 3066, 2995, 2926, 2858, 2792, 2726, 2662, 2599, 2538,
2478, 2420, 2362, 2305, 2249, 2195, 2141, 2089, 2037, 1988,
1939, 1891, 1844, 1799, 1754, 1711, 1668, 1626, 1584, 1542,
1500, 1459, 1418, 1380, 1342, 1305, 1269, 1234, 1199, 1166,
1133, 1102, 1071, 1041, 1012, 983, 954, 926, 899, 872,
847, 822, 798, 774, 751, 728, 707, 686, 666, 646,
627, 608, 589, 570, 552, 534, 517, 500, 484, 468,
453, 438, 424, 410, 397, 384, 372, 360, 348, 336,
325, 314, 303, 293, 283, 273, 264, 255, 246, 237,
229, 221, 213, 205, 197, 189, 181, 174, 167, 160,
154, 148, 142, 136, 131, 126, 121, 116, 111, 106,
101, 97, 93, 89, 85, 81, 77, 73, 70, 67,
64, 61, 58, 55, 52, 49, 46, 43, 40, 37,
35, 33, 31, 29, 27, 25, 23, 21, 19, 17,
16, 15, 14, 13, 12, 11, 10, 9, 8, 7,
6, 5, 4, 3, 2, 1, 0
},
{
16384, 16218, 16052, 15886, 15720, 15554, 15389, 15224, 15059, 14895,
14731, 14567, 14403, 14240, 14077, 13915, 13753, 13591, 13429, 13269,
13109, 12950, 12791, 12633, 12476, 12320, 12164, 12009, 11854, 11701,
11548, 11396, 11244, 11092, 10940, 10790, 10640, 10492, 10344, 10198,
10052, 9908, 9764, 9622, 9481, 9342, 9203, 9066, 8929, 8793,
8657, 8524, 8391, 8261, 8131, 8003, 7875, 7749, 7624, 7502,
7380, 7260, 7140, 7022, 6904, 6786, 6668, 6551, 6435, 6322,
6209, 6099, 5989, 5881, 5773, 5668, 5563, 5461, 5359, 5260,
5161, 5063, 4965, 4871, 4777, 4686, 4595, 4506, 4417, 4331,
4245, 4162, 4079, 3999, 3919, 3841, 3763, 3685, 3607, 3530,
3454, 3380, 3307, 3236, 3166, 3097, 3029, 2963, 2897, 2834,
2771, 2710, 2650, 2591, 2532, 2475, 2418, 2363, 2309, 2257,
2205, 2155, 2105, 2057, 2009, 1963, 1918, 1873, 1828, 1783,
1738, 1694, 1650, 1607, 1565, 1524, 1484, 1445, 1407, 1369,
1333, 1297, 1263, 1229, 1197, 1165, 1134, 1103, 1073, 1043,
1015, 987, 960, 933, 907, 882, 858, 834, 811, 788,
766, 744, 722, 700, 679, 658, 638, 618, 599, 581,
563, 545, 528, 511, 495, 480, 465, 451, 437, 423,
410, 397, 384, 372, 360, 348, 337, 326, 315, 305,
295, 285, 275, 265, 255, 245, 236, 227, 219, 211,
203, 195, 188, 181, 174, 167, 161, 155, 149, 143,
137, 131, 126, 121, 116, 111, 106, 101, 97, 93,
89, 85, 81, 77, 73, 69, 65, 61, 58, 55,
52, 49, 46, 43, 40, 37, 34, 32, 30, 28,
26, 24, 22, 20, 18, 16, 14, 12, 10, 8,
6, 5, 4, 3, 2, 1, 0
}
};
static const uint16_t * const cf_table[16] = {
cf_tables_1[0], cf_tables_1[1], cf_tables_1[2], cf_tables_2[0],
cf_tables_2[1], cf_tables_2[2], cf_tables_2[3], cf_tables_2[4],
cf_tables_2[5], cf_tables_2[6], cf_tables_2[7], cf_tables_3[0],
cf_tables_3[1], cf_tables_3[2], cf_tables_3[3], cf_tables_3[4]
};
/** Initialize a given lookup table using a given delta
*/
static void bgmc_lut_fillp(uint8_t *lut, int *lut_status,
int delta)
{
unsigned int sx, i;
for (sx = 0; sx < 16; sx++)
for (i = 0; i < LUT_SIZE; i++) {
unsigned int target = (i + 1) << (FREQ_BITS - LUT_BITS);
unsigned int symbol = 1 << delta;
while (cf_table[sx][symbol] > target)
symbol += 1 << delta;
*lut++ = symbol >> delta;
}
*lut_status = delta;
}
/** Retune the index of a suitable lookup table for a given delta
*/
static uint8_t* bgmc_lut_getp(uint8_t *lut, int *lut_status,
int delta)
{
unsigned int i = av_clip(delta, 0, LUT_BUFF - 1);
lut += (i * LUT_SIZE) << 4;
if (lut_status[i] != delta)
bgmc_lut_fillp(lut, &lut_status[i], delta);
return lut;
}
/** Initialize the lookup table arrays
*/
int ff_bgmc_init(AVCodecContext *avctx, uint8_t **cf_lut, int **cf_lut_status)
{
*cf_lut = av_malloc(sizeof(*cf_lut ) * LUT_BUFF * 16 * LUT_SIZE);
*cf_lut_status = av_malloc(sizeof(*cf_lut_status) * LUT_BUFF);
if (!cf_lut || !cf_lut_status) {
ff_bgmc_end(cf_lut, cf_lut_status);
av_log(avctx, AV_LOG_ERROR, "Allocating buffer memory failed.\n");
return AVERROR(ENOMEM);
} else {
// initialize lut_status buffer to a value never used to compare against
memset(*cf_lut_status, -1, sizeof(*cf_lut_status) * LUT_BUFF);
}
return 0;
}
/** Release the lookup table arrays
*/
void ff_bgmc_end(uint8_t **cf_lut, int **cf_lut_status)
{
av_freep(cf_lut);
av_freep(cf_lut_status);
}
/** Initialize decoding and reads the first value
*/
void ff_bgmc_decode_init(GetBitContext *gb,
unsigned int *h, unsigned int *l, unsigned int *v)
{
*h = TOP_VALUE;
*l = 0;
*v = get_bits_long(gb, VALUE_BITS);
}
/** Finish decoding
*/
void ff_bgmc_decode_end(GetBitContext *gb)
{
skip_bits_long(gb, -(VALUE_BITS - 2));
}
/** Read and decode a block Gilbert-Moore coded symbol
*/
void ff_bgmc_decode(GetBitContext *gb, unsigned int num, int32_t *dst,
int delta, unsigned int sx,
unsigned int *h, unsigned int *l, unsigned int *v,
uint8_t *cf_lut, int *cf_lut_status)
{
unsigned int i;
uint8_t *lut = bgmc_lut_getp(cf_lut, cf_lut_status, delta);
// read current state
unsigned int high = *h;
unsigned int low = *l;
unsigned int value = *v;
lut += sx * LUT_SIZE;
// decode num samples
for (i = 0; i < num; i++) {
unsigned int range = high - low + 1;
unsigned int target = (((value - low + 1) << FREQ_BITS) - 1) / range;
unsigned int symbol = lut[target >> (FREQ_BITS - LUT_BITS)] << delta;
while (cf_table[sx][symbol] > target)
symbol += 1 << delta;
symbol = (symbol >> delta) - 1;
high = low + ((range * cf_table[sx][(symbol ) << delta] - (1 << FREQ_BITS)) >> FREQ_BITS);
low = low + ((range * cf_table[sx][(symbol + 1) << delta] ) >> FREQ_BITS);
while (1) {
if (high >= HALF) {
if (low >= HALF) {
value -= HALF;
low -= HALF;
high -= HALF;
} else if (low >= FIRST_QTR && high < THIRD_QTR) {
value -= FIRST_QTR;
low -= FIRST_QTR;
high -= FIRST_QTR;
} else break;
}
low *= 2;
high = 2 * high + 1;
value = 2 * value + get_bits1(gb);
}
*dst++ = symbol;
}
// save current state
*h = high;
*l = low;
*v = value;
}