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17-Zip method IDs for 7z and xz archives
2---------------------------------------
3
4Version: 16.03
5Date: 2016-09-27
6
7Each compression or crypto method in 7z is associated with unique binary value (ID).
8The length of ID in bytes is arbitrary but it can not exceed 63 bits (8 bytes).
9
10xz and 7z formats use same ID map.
11
12If 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
28List of defined IDs
29-------------------
30
3100 - Copy
32
3303 - Delta
3404 - BCJ (x86)
3505 - PPC (big-endian)
3606 - IA64
3707 - ARM (little-endian)
3808 - ARMT (little-endian)
3909 - SPARC
40
4121 - LZMA2
42
4302.. - Common
44   03 [Swap]
45      - 2 Swap2
46      - 4 Swap4
47
4803.. - 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
7804.. - 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      10 xx - reserved (LZHAM)
126      11 xx - reserved (Zstd)
127
128
12906.. - Crypto
130
131   F0 - Ciphers without hashing algo
132
133      01 - [AES]
134         0x - AES-128
135         4x - AES-192
136         8x - AES-256
137         Cx - AES
138
139         x0 - ECB
140         x1 - CBC
141         x2 - CFB
142         x3 - OFB
143         x4 - CTR
144
145   F1 - Combine Ciphers
146
147      01 - [Zip]
148         01 - ZipCrypto (Main Zip crypto algo)
149
150      03 - [RAR]
151         02 -
152         03 - Rar29AES (AES-128 + modified SHA-1)
153
154      07 - [7z]
155         01 - 7zAES (AES-256 + SHA-256)
156
157
158---
159End of document
160