1 7-Zip method IDs for 7z and xz archives 2 --------------------------------------- 3 4 Version: 18.06 5 Date: 2018-06-30 6 7 Each compression or crypto method in 7z is associated with unique binary value (ID). 8 The length of ID in bytes is arbitrary but it can not exceed 63 bits (8 bytes). 9 10 xz and 7z formats use same ID map. 11 12 If you want to add some new ID, you have two ways: 13 1) Write request for allocating IDs to 7-Zip developers. 14 2) Generate 8-bytes ID: 15 16 3F ZZ ZZ ZZ ZZ ZZ MM MM 17 18 3F - Prefix for random IDs (1 byte) 19 ZZ ZZ ZZ ZZ ZZ - Developer ID (5 bytes). Use real random bytes. 20 21 MM MM - Method ID (2 bytes) 22 23 You can notify 7-Zip developers about your Developer ID / Method ID. 24 25 Note: Use new ID, if old codec can not decode data encoded with new version. 26 27 28 List of defined IDs 29 ------------------- 30 31 00 - Copy 32 33 03 - Delta 34 04 - BCJ (x86) 35 05 - PPC (big-endian) 36 06 - IA64 37 07 - ARM (little-endian) 38 08 - ARMT (little-endian) 39 09 - SPARC 40 41 21 - LZMA2 42 43 02.. - Common 44 03 [Swap] 45 - 2 Swap2 46 - 4 Swap4 47 48 03.. - 7z 49 01 - 50 01 - LZMA 51 52 03 - [Branch Codecs] 53 01 - [x86 Codecs] 54 03 - BCJ 55 1B - BCJ2 (4 packed streams) 56 02 - 57 05 - PPC (big-endian) 58 03 - 59 01 - Alpha 60 04 - 61 01 - IA64 62 05 - 63 01 - ARM (little-endian) 64 06 - 65 05 - M68 (big-endian) 66 07 - 67 01 - ARMT (little-endian) 68 08 - 69 05 - SPARC 70 71 04 - 72 01 - PPMD 73 74 7F - 75 01 - experimental method. 76 77 78 04.. - Misc codecs 79 80 00 - Reserved 81 82 01 - [Zip] 83 00 - Copy (not used. Use {00} instead) 84 01 - Shrink 85 06 - Implode 86 08 - Deflate 87 09 - Deflate64 88 0A - Imploding 89 0C - BZip2 (not used. Use {040202} instead) 90 0E - LZMA (LZMA-zip) 91 5F - xz 92 60 - Jpeg 93 61 - WavPack 94 62 - PPMd (PPMd-zip) 95 63 - wzAES 96 97 02 - 98 02 - BZip2 99 100 03 - [Rar] 101 01 - Rar1 102 02 - Rar2 103 03 - Rar3 104 05 - Rar5 105 106 04 - [Arj] 107 01 - Arj(1,2,3) 108 02 - Arj4 109 110 05 - [Z] 111 112 06 - [Lzh] 113 114 07 - Reserved for 7z 115 116 08 - [Cab] 117 118 09 - [NSIS] 119 01 - DeflateNSIS 120 02 - BZip2NSIS 121 122 F7 - External codecs (that are not included to 7-Zip) 123 124 0x xx - reserved 125 126 10 xx - reserved (LZHAM) 127 01 - LZHAM 128 129 11 xx - reserved (Tino Reichardt) 130 01 - ZSTD 131 02 - BROTLI 132 04 - LZ4 133 05 - LZ5 134 06 - LIZARD 135 136 12 xx - reserverd (Denis Anisimov) 137 138 01 - WavPack2 139 FE - eSplitter 140 FF - RawSplitter 141 142 143 06.. - Crypto 144 145 F0 - Ciphers without hashing algo 146 147 01 - [AES] 148 0x - AES-128 149 4x - AES-192 150 8x - AES-256 151 Cx - AES 152 153 x0 - ECB 154 x1 - CBC 155 x2 - CFB 156 x3 - OFB 157 x4 - CTR 158 159 F1 - Combine Ciphers 160 161 01 - [Zip] 162 01 - ZipCrypto (Main Zip crypto algo) 163 164 03 - [RAR] 165 02 - 166 03 - Rar29AES (AES-128 + modified SHA-1) 167 168 07 - [7z] 169 01 - 7zAES (AES-256 + SHA-256) 170 171 172 --- 173 End of document 174
