Libav
crc.c
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "config.h"
22 
23 #include "bswap.h"
24 #include "common.h"
25 #include "crc.h"
26 
27 #if CONFIG_HARDCODED_TABLES
28 static const AVCRC av_crc_table[AV_CRC_MAX][257] = {
29  [AV_CRC_8_ATM] = {
30  0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15, 0x38, 0x3F, 0x36, 0x31,
31  0x24, 0x23, 0x2A, 0x2D, 0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
32  0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D, 0xE0, 0xE7, 0xEE, 0xE9,
33  0xFC, 0xFB, 0xF2, 0xF5, 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
34  0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85, 0xA8, 0xAF, 0xA6, 0xA1,
35  0xB4, 0xB3, 0xBA, 0xBD, 0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
36  0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA, 0xB7, 0xB0, 0xB9, 0xBE,
37  0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
38  0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32, 0x1F, 0x18, 0x11, 0x16,
39  0x03, 0x04, 0x0D, 0x0A, 0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
40  0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A, 0x89, 0x8E, 0x87, 0x80,
41  0x95, 0x92, 0x9B, 0x9C, 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
42  0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC, 0xC1, 0xC6, 0xCF, 0xC8,
43  0xDD, 0xDA, 0xD3, 0xD4, 0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
44  0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44, 0x19, 0x1E, 0x17, 0x10,
45  0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
46  0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F,
47  0x6A, 0x6D, 0x64, 0x63, 0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
48  0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13, 0xAE, 0xA9, 0xA0, 0xA7,
49  0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
50  0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB, 0xE6, 0xE1, 0xE8, 0xEF,
51  0xFA, 0xFD, 0xF4, 0xF3, 0x01
52  },
53  [AV_CRC_16_ANSI] = {
54  0x0000, 0x0580, 0x0F80, 0x0A00, 0x1B80, 0x1E00, 0x1400, 0x1180,
55  0x3380, 0x3600, 0x3C00, 0x3980, 0x2800, 0x2D80, 0x2780, 0x2200,
56  0x6380, 0x6600, 0x6C00, 0x6980, 0x7800, 0x7D80, 0x7780, 0x7200,
57  0x5000, 0x5580, 0x5F80, 0x5A00, 0x4B80, 0x4E00, 0x4400, 0x4180,
58  0xC380, 0xC600, 0xCC00, 0xC980, 0xD800, 0xDD80, 0xD780, 0xD200,
59  0xF000, 0xF580, 0xFF80, 0xFA00, 0xEB80, 0xEE00, 0xE400, 0xE180,
60  0xA000, 0xA580, 0xAF80, 0xAA00, 0xBB80, 0xBE00, 0xB400, 0xB180,
61  0x9380, 0x9600, 0x9C00, 0x9980, 0x8800, 0x8D80, 0x8780, 0x8200,
62  0x8381, 0x8601, 0x8C01, 0x8981, 0x9801, 0x9D81, 0x9781, 0x9201,
63  0xB001, 0xB581, 0xBF81, 0xBA01, 0xAB81, 0xAE01, 0xA401, 0xA181,
64  0xE001, 0xE581, 0xEF81, 0xEA01, 0xFB81, 0xFE01, 0xF401, 0xF181,
65  0xD381, 0xD601, 0xDC01, 0xD981, 0xC801, 0xCD81, 0xC781, 0xC201,
66  0x4001, 0x4581, 0x4F81, 0x4A01, 0x5B81, 0x5E01, 0x5401, 0x5181,
67  0x7381, 0x7601, 0x7C01, 0x7981, 0x6801, 0x6D81, 0x6781, 0x6201,
68  0x2381, 0x2601, 0x2C01, 0x2981, 0x3801, 0x3D81, 0x3781, 0x3201,
69  0x1001, 0x1581, 0x1F81, 0x1A01, 0x0B81, 0x0E01, 0x0401, 0x0181,
70  0x0383, 0x0603, 0x0C03, 0x0983, 0x1803, 0x1D83, 0x1783, 0x1203,
71  0x3003, 0x3583, 0x3F83, 0x3A03, 0x2B83, 0x2E03, 0x2403, 0x2183,
72  0x6003, 0x6583, 0x6F83, 0x6A03, 0x7B83, 0x7E03, 0x7403, 0x7183,
73  0x5383, 0x5603, 0x5C03, 0x5983, 0x4803, 0x4D83, 0x4783, 0x4203,
74  0xC003, 0xC583, 0xCF83, 0xCA03, 0xDB83, 0xDE03, 0xD403, 0xD183,
75  0xF383, 0xF603, 0xFC03, 0xF983, 0xE803, 0xED83, 0xE783, 0xE203,
76  0xA383, 0xA603, 0xAC03, 0xA983, 0xB803, 0xBD83, 0xB783, 0xB203,
77  0x9003, 0x9583, 0x9F83, 0x9A03, 0x8B83, 0x8E03, 0x8403, 0x8183,
78  0x8002, 0x8582, 0x8F82, 0x8A02, 0x9B82, 0x9E02, 0x9402, 0x9182,
79  0xB382, 0xB602, 0xBC02, 0xB982, 0xA802, 0xAD82, 0xA782, 0xA202,
80  0xE382, 0xE602, 0xEC02, 0xE982, 0xF802, 0xFD82, 0xF782, 0xF202,
81  0xD002, 0xD582, 0xDF82, 0xDA02, 0xCB82, 0xCE02, 0xC402, 0xC182,
82  0x4382, 0x4602, 0x4C02, 0x4982, 0x5802, 0x5D82, 0x5782, 0x5202,
83  0x7002, 0x7582, 0x7F82, 0x7A02, 0x6B82, 0x6E02, 0x6402, 0x6182,
84  0x2002, 0x2582, 0x2F82, 0x2A02, 0x3B82, 0x3E02, 0x3402, 0x3182,
85  0x1382, 0x1602, 0x1C02, 0x1982, 0x0802, 0x0D82, 0x0782, 0x0202,
86  0x0001
87  },
88  [AV_CRC_16_CCITT] = {
89  0x0000, 0x2110, 0x4220, 0x6330, 0x8440, 0xA550, 0xC660, 0xE770,
90  0x0881, 0x2991, 0x4AA1, 0x6BB1, 0x8CC1, 0xADD1, 0xCEE1, 0xEFF1,
91  0x3112, 0x1002, 0x7332, 0x5222, 0xB552, 0x9442, 0xF772, 0xD662,
92  0x3993, 0x1883, 0x7BB3, 0x5AA3, 0xBDD3, 0x9CC3, 0xFFF3, 0xDEE3,
93  0x6224, 0x4334, 0x2004, 0x0114, 0xE664, 0xC774, 0xA444, 0x8554,
94  0x6AA5, 0x4BB5, 0x2885, 0x0995, 0xEEE5, 0xCFF5, 0xACC5, 0x8DD5,
95  0x5336, 0x7226, 0x1116, 0x3006, 0xD776, 0xF666, 0x9556, 0xB446,
96  0x5BB7, 0x7AA7, 0x1997, 0x3887, 0xDFF7, 0xFEE7, 0x9DD7, 0xBCC7,
97  0xC448, 0xE558, 0x8668, 0xA778, 0x4008, 0x6118, 0x0228, 0x2338,
98  0xCCC9, 0xEDD9, 0x8EE9, 0xAFF9, 0x4889, 0x6999, 0x0AA9, 0x2BB9,
99  0xF55A, 0xD44A, 0xB77A, 0x966A, 0x711A, 0x500A, 0x333A, 0x122A,
100  0xFDDB, 0xDCCB, 0xBFFB, 0x9EEB, 0x799B, 0x588B, 0x3BBB, 0x1AAB,
101  0xA66C, 0x877C, 0xE44C, 0xC55C, 0x222C, 0x033C, 0x600C, 0x411C,
102  0xAEED, 0x8FFD, 0xECCD, 0xCDDD, 0x2AAD, 0x0BBD, 0x688D, 0x499D,
103  0x977E, 0xB66E, 0xD55E, 0xF44E, 0x133E, 0x322E, 0x511E, 0x700E,
104  0x9FFF, 0xBEEF, 0xDDDF, 0xFCCF, 0x1BBF, 0x3AAF, 0x599F, 0x788F,
105  0x8891, 0xA981, 0xCAB1, 0xEBA1, 0x0CD1, 0x2DC1, 0x4EF1, 0x6FE1,
106  0x8010, 0xA100, 0xC230, 0xE320, 0x0450, 0x2540, 0x4670, 0x6760,
107  0xB983, 0x9893, 0xFBA3, 0xDAB3, 0x3DC3, 0x1CD3, 0x7FE3, 0x5EF3,
108  0xB102, 0x9012, 0xF322, 0xD232, 0x3542, 0x1452, 0x7762, 0x5672,
109  0xEAB5, 0xCBA5, 0xA895, 0x8985, 0x6EF5, 0x4FE5, 0x2CD5, 0x0DC5,
110  0xE234, 0xC324, 0xA014, 0x8104, 0x6674, 0x4764, 0x2454, 0x0544,
111  0xDBA7, 0xFAB7, 0x9987, 0xB897, 0x5FE7, 0x7EF7, 0x1DC7, 0x3CD7,
112  0xD326, 0xF236, 0x9106, 0xB016, 0x5766, 0x7676, 0x1546, 0x3456,
113  0x4CD9, 0x6DC9, 0x0EF9, 0x2FE9, 0xC899, 0xE989, 0x8AB9, 0xABA9,
114  0x4458, 0x6548, 0x0678, 0x2768, 0xC018, 0xE108, 0x8238, 0xA328,
115  0x7DCB, 0x5CDB, 0x3FEB, 0x1EFB, 0xF98B, 0xD89B, 0xBBAB, 0x9ABB,
116  0x754A, 0x545A, 0x376A, 0x167A, 0xF10A, 0xD01A, 0xB32A, 0x923A,
117  0x2EFD, 0x0FED, 0x6CDD, 0x4DCD, 0xAABD, 0x8BAD, 0xE89D, 0xC98D,
118  0x267C, 0x076C, 0x645C, 0x454C, 0xA23C, 0x832C, 0xE01C, 0xC10C,
119  0x1FEF, 0x3EFF, 0x5DCF, 0x7CDF, 0x9BAF, 0xBABF, 0xD98F, 0xF89F,
120  0x176E, 0x367E, 0x554E, 0x745E, 0x932E, 0xB23E, 0xD10E, 0xF01E,
121  0x0001
122  },
123  [AV_CRC_32_IEEE] = {
124  0x00000000, 0xB71DC104, 0x6E3B8209, 0xD926430D, 0xDC760413, 0x6B6BC517,
125  0xB24D861A, 0x0550471E, 0xB8ED0826, 0x0FF0C922, 0xD6D68A2F, 0x61CB4B2B,
126  0x649B0C35, 0xD386CD31, 0x0AA08E3C, 0xBDBD4F38, 0x70DB114C, 0xC7C6D048,
127  0x1EE09345, 0xA9FD5241, 0xACAD155F, 0x1BB0D45B, 0xC2969756, 0x758B5652,
128  0xC836196A, 0x7F2BD86E, 0xA60D9B63, 0x11105A67, 0x14401D79, 0xA35DDC7D,
129  0x7A7B9F70, 0xCD665E74, 0xE0B62398, 0x57ABE29C, 0x8E8DA191, 0x39906095,
130  0x3CC0278B, 0x8BDDE68F, 0x52FBA582, 0xE5E66486, 0x585B2BBE, 0xEF46EABA,
131  0x3660A9B7, 0x817D68B3, 0x842D2FAD, 0x3330EEA9, 0xEA16ADA4, 0x5D0B6CA0,
132  0x906D32D4, 0x2770F3D0, 0xFE56B0DD, 0x494B71D9, 0x4C1B36C7, 0xFB06F7C3,
133  0x2220B4CE, 0x953D75CA, 0x28803AF2, 0x9F9DFBF6, 0x46BBB8FB, 0xF1A679FF,
134  0xF4F63EE1, 0x43EBFFE5, 0x9ACDBCE8, 0x2DD07DEC, 0x77708634, 0xC06D4730,
135  0x194B043D, 0xAE56C539, 0xAB068227, 0x1C1B4323, 0xC53D002E, 0x7220C12A,
136  0xCF9D8E12, 0x78804F16, 0xA1A60C1B, 0x16BBCD1F, 0x13EB8A01, 0xA4F64B05,
137  0x7DD00808, 0xCACDC90C, 0x07AB9778, 0xB0B6567C, 0x69901571, 0xDE8DD475,
138  0xDBDD936B, 0x6CC0526F, 0xB5E61162, 0x02FBD066, 0xBF469F5E, 0x085B5E5A,
139  0xD17D1D57, 0x6660DC53, 0x63309B4D, 0xD42D5A49, 0x0D0B1944, 0xBA16D840,
140  0x97C6A5AC, 0x20DB64A8, 0xF9FD27A5, 0x4EE0E6A1, 0x4BB0A1BF, 0xFCAD60BB,
141  0x258B23B6, 0x9296E2B2, 0x2F2BAD8A, 0x98366C8E, 0x41102F83, 0xF60DEE87,
142  0xF35DA999, 0x4440689D, 0x9D662B90, 0x2A7BEA94, 0xE71DB4E0, 0x500075E4,
143  0x892636E9, 0x3E3BF7ED, 0x3B6BB0F3, 0x8C7671F7, 0x555032FA, 0xE24DF3FE,
144  0x5FF0BCC6, 0xE8ED7DC2, 0x31CB3ECF, 0x86D6FFCB, 0x8386B8D5, 0x349B79D1,
145  0xEDBD3ADC, 0x5AA0FBD8, 0xEEE00C69, 0x59FDCD6D, 0x80DB8E60, 0x37C64F64,
146  0x3296087A, 0x858BC97E, 0x5CAD8A73, 0xEBB04B77, 0x560D044F, 0xE110C54B,
147  0x38368646, 0x8F2B4742, 0x8A7B005C, 0x3D66C158, 0xE4408255, 0x535D4351,
148  0x9E3B1D25, 0x2926DC21, 0xF0009F2C, 0x471D5E28, 0x424D1936, 0xF550D832,
149  0x2C769B3F, 0x9B6B5A3B, 0x26D61503, 0x91CBD407, 0x48ED970A, 0xFFF0560E,
150  0xFAA01110, 0x4DBDD014, 0x949B9319, 0x2386521D, 0x0E562FF1, 0xB94BEEF5,
151  0x606DADF8, 0xD7706CFC, 0xD2202BE2, 0x653DEAE6, 0xBC1BA9EB, 0x0B0668EF,
152  0xB6BB27D7, 0x01A6E6D3, 0xD880A5DE, 0x6F9D64DA, 0x6ACD23C4, 0xDDD0E2C0,
153  0x04F6A1CD, 0xB3EB60C9, 0x7E8D3EBD, 0xC990FFB9, 0x10B6BCB4, 0xA7AB7DB0,
154  0xA2FB3AAE, 0x15E6FBAA, 0xCCC0B8A7, 0x7BDD79A3, 0xC660369B, 0x717DF79F,
155  0xA85BB492, 0x1F467596, 0x1A163288, 0xAD0BF38C, 0x742DB081, 0xC3307185,
156  0x99908A5D, 0x2E8D4B59, 0xF7AB0854, 0x40B6C950, 0x45E68E4E, 0xF2FB4F4A,
157  0x2BDD0C47, 0x9CC0CD43, 0x217D827B, 0x9660437F, 0x4F460072, 0xF85BC176,
158  0xFD0B8668, 0x4A16476C, 0x93300461, 0x242DC565, 0xE94B9B11, 0x5E565A15,
159  0x87701918, 0x306DD81C, 0x353D9F02, 0x82205E06, 0x5B061D0B, 0xEC1BDC0F,
160  0x51A69337, 0xE6BB5233, 0x3F9D113E, 0x8880D03A, 0x8DD09724, 0x3ACD5620,
161  0xE3EB152D, 0x54F6D429, 0x7926A9C5, 0xCE3B68C1, 0x171D2BCC, 0xA000EAC8,
162  0xA550ADD6, 0x124D6CD2, 0xCB6B2FDF, 0x7C76EEDB, 0xC1CBA1E3, 0x76D660E7,
163  0xAFF023EA, 0x18EDE2EE, 0x1DBDA5F0, 0xAAA064F4, 0x738627F9, 0xC49BE6FD,
164  0x09FDB889, 0xBEE0798D, 0x67C63A80, 0xD0DBFB84, 0xD58BBC9A, 0x62967D9E,
165  0xBBB03E93, 0x0CADFF97, 0xB110B0AF, 0x060D71AB, 0xDF2B32A6, 0x6836F3A2,
166  0x6D66B4BC, 0xDA7B75B8, 0x035D36B5, 0xB440F7B1, 0x00000001
167  },
168  [AV_CRC_32_IEEE_LE] = {
169  0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F,
170  0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
171  0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2,
172  0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
173  0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9,
174  0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
175  0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C,
176  0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
177  0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423,
178  0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
179  0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106,
180  0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
181  0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D,
182  0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
183  0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950,
184  0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
185  0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7,
186  0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
187  0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA,
188  0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
189  0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81,
190  0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
191  0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84,
192  0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
193  0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB,
194  0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
195  0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E,
196  0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
197  0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55,
198  0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
199  0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28,
200  0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
201  0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F,
202  0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
203  0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242,
204  0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
205  0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69,
206  0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
207  0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC,
208  0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
209  0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693,
210  0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
211  0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D, 0x00000001
212  },
213  [AV_CRC_16_ANSI_LE] = {
214  0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
215  0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
216  0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
217  0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
218  0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
219  0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
220  0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
221  0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
222  0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
223  0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
224  0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
225  0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
226  0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
227  0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
228  0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
229  0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
230  0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
231  0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
232  0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
233  0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
234  0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
235  0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
236  0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
237  0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
238  0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
239  0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
240  0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
241  0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
242  0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
243  0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
244  0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
245  0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040,
246  0x0001
247  },
248 };
249 #else
250 static struct {
253  uint32_t poly;
255  [AV_CRC_8_ATM] = { 0, 8, 0x07 },
256  [AV_CRC_16_ANSI] = { 0, 16, 0x8005 },
257  [AV_CRC_16_CCITT] = { 0, 16, 0x1021 },
258  [AV_CRC_32_IEEE] = { 0, 32, 0x04C11DB7 },
259  [AV_CRC_32_IEEE_LE] = { 1, 32, 0xEDB88320 },
260  [AV_CRC_16_ANSI_LE] = { 1, 16, 0xA001 },
261 };
263 #endif
264 
265 int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size)
266 {
267  unsigned i, j;
268  uint32_t c;
269 
270  if (bits < 8 || bits > 32 || poly >= (1LL << bits))
271  return -1;
272  if (ctx_size != sizeof(AVCRC) * 257 && ctx_size != sizeof(AVCRC) * 1024)
273  return -1;
274 
275  for (i = 0; i < 256; i++) {
276  if (le) {
277  for (c = i, j = 0; j < 8; j++)
278  c = (c >> 1) ^ (poly & (-(c & 1)));
279  ctx[i] = c;
280  } else {
281  for (c = i << 24, j = 0; j < 8; j++)
282  c = (c << 1) ^ ((poly << (32 - bits)) & (((int32_t) c) >> 31));
283  ctx[i] = av_bswap32(c);
284  }
285  }
286  ctx[256] = 1;
287 #if !CONFIG_SMALL
288  if (ctx_size >= sizeof(AVCRC) * 1024)
289  for (i = 0; i < 256; i++)
290  for (j = 0; j < 3; j++)
291  ctx[256 * (j + 1) + i] =
292  (ctx[256 * j + i] >> 8) ^ ctx[ctx[256 * j + i] & 0xFF];
293 #endif
294 
295  return 0;
296 }
297 
299 {
300 #if !CONFIG_HARDCODED_TABLES
301  if (!av_crc_table[crc_id][FF_ARRAY_ELEMS(av_crc_table[crc_id]) - 1])
302  if (av_crc_init(av_crc_table[crc_id],
303  av_crc_table_params[crc_id].le,
304  av_crc_table_params[crc_id].bits,
305  av_crc_table_params[crc_id].poly,
306  sizeof(av_crc_table[crc_id])) < 0)
307  return NULL;
308 #endif
309  return av_crc_table[crc_id];
310 }
311 
312 uint32_t av_crc(const AVCRC *ctx, uint32_t crc,
313  const uint8_t *buffer, size_t length)
314 {
315  const uint8_t *end = buffer + length;
316 
317 #if !CONFIG_SMALL
318  if (!ctx[256]) {
319  while (((intptr_t) buffer & 3) && buffer < end)
320  crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
321 
322  while (buffer < end - 3) {
323  crc ^= av_le2ne32(*(const uint32_t *) buffer); buffer += 4;
324  crc = ctx[3 * 256 + ( crc & 0xFF)] ^
325  ctx[2 * 256 + ((crc >> 8 ) & 0xFF)] ^
326  ctx[1 * 256 + ((crc >> 16) & 0xFF)] ^
327  ctx[0 * 256 + ((crc >> 24) )];
328  }
329  }
330 #endif
331  while (buffer < end)
332  crc = ctx[((uint8_t) crc) ^ *buffer++] ^ (crc >> 8);
333 
334  return crc;
335 }
Definition: crc.h:37
uint32_t poly
Definition: crc.c:253
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:312
#define FF_ARRAY_ELEMS(a)
#define av_le2ne32(x)
Definition: bswap.h:98
int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size)
Initialize a CRC table.
Definition: crc.c:265
static char buffer[20]
Definition: seek.c:32
uint8_t bits
Definition: crc.c:252
uint8_t
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:298
AVCRCId
Definition: crc.h:30
static AVCRC av_crc_table[AV_CRC_MAX][257]
Definition: crc.c:262
static struct @157 av_crc_table_params[AV_CRC_MAX]
int32_t
AVFormatContext * ctx
Definition: movenc.c:48
uint8_t le
Definition: crc.c:251
NULL
Definition: eval.c:55
#define av_bswap32
Definition: bswap.h:33
byte swapping routines
common internal and external API header
uint32_t AVCRC
Definition: crc.h:28