compress revision 133359
1181624Skmacy 2181624Skmacy#------------------------------------------------------------------------------ 3181624Skmacy# compress: file(1) magic for pure-compression formats (no archives) 4181624Skmacy# 5181624Skmacy# compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, etc. 6181624Skmacy# 7181624Skmacy# Formats for various forms of compressed data 8181624Skmacy# Formats for "compress" proper have been moved into "compress.c", 9181624Skmacy# because it tries to uncompress it to figure out what's inside. 10181624Skmacy 11181624Skmacy# standard unix compress 12181624Skmacy0 string \037\235 compress'd data 13181624Skmacy>2 byte&0x80 >0 block compressed 14181624Skmacy>2 byte&0x1f x %d bits 15181624Skmacy 16181624Skmacy# gzip (GNU zip, not to be confused with Info-ZIP or PKWARE zip archiver) 17181624Skmacy# Edited by Chris Chittleborough <cchittleborough@yahoo.com.au>, March 2002 18181624Skmacy# * Original filename is only at offset 10 if "extra field" absent 19181624Skmacy# * Produce shorter output - notably, only report compression methods 20181624Skmacy# other than 8 ("deflate", the only method defined in RFC 1952). 21181624Skmacy0 string \037\213 gzip compressed data 22181624Skmacy>2 byte <8 \b, reserved method 23181624Skmacy>2 byte >8 \b, unknown method 24181624Skmacy>3 byte &0x01 \b, ASCII 25181624Skmacy>3 byte &0x02 \b, continuation 26181624Skmacy>3 byte &0x04 \b, extra field 27181624Skmacy>3 byte&0xC =0x08 28181624Skmacy>>10 string x \b, was "%s" 29181624Skmacy>9 byte =0x00 \b, from MS-DOS 30181624Skmacy>9 byte =0x01 \b, from Amiga 31181624Skmacy>9 byte =0x02 \b, from VMS 32181624Skmacy>9 byte =0x03 \b, from Unix 33181624Skmacy>9 byte =0x05 \b, from Atari 34181624Skmacy>9 byte =0x06 \b, from OS/2 35181624Skmacy>9 byte =0x07 \b, from MacOS 36181624Skmacy>9 byte =0x0A \b, from Tops/20 37181624Skmacy>9 byte =0x0B \b, from Win/32 38181624Skmacy>3 byte &0x10 \b, comment 39181624Skmacy>3 byte &0x20 \b, encrypted 40181624Skmacy### >4 ledate x last modified: %s, 41181624Skmacy>8 byte 2 \b, max compression 42181624Skmacy>8 byte 4 \b, max speed 43181624Skmacy 44181624Skmacy# packed data, Huffman (minimum redundancy) codes on a byte-by-byte basis 45181624Skmacy0 string \037\036 packed data 46181624Skmacy>2 belong >1 \b, %d characters originally 47181624Skmacy>2 belong =1 \b, %d character originally 48181624Skmacy# 49181624Skmacy# This magic number is byte-order-independent. 50181624Skmacy0 short 0x1f1f old packed data 51181624Skmacy 52181624Skmacy# XXX - why *two* entries for "compacted data", one of which is 53181624Skmacy# byte-order independent, and one of which is byte-order dependent? 54181624Skmacy# 55181624Skmacy0 short 0x1fff compacted data 56181624Skmacy# This string is valid for SunOS (BE) and a matching "short" is listed 57181624Skmacy# in the Ultrix (LE) magic file. 58181624Skmacy0 string \377\037 compacted data 59181624Skmacy0 short 0145405 huf output 60181624Skmacy 61181624Skmacy# bzip2 62181624Skmacy0 string BZh bzip2 compressed data 63181624Skmacy>3 byte >47 \b, block size = %c00k 64181624Skmacy 65181624Skmacy# squeeze and crunch 66181624Skmacy# Michael Haardt <michael@cantor.informatik.rwth-aachen.de> 67181624Skmacy0 beshort 0x76FF squeezed data, 68181624Skmacy>4 string x original name %s 69181624Skmacy0 beshort 0x76FE crunched data, 70181624Skmacy>2 string x original name %s 71181624Skmacy0 beshort 0x76FD LZH compressed data, 72181624Skmacy>2 string x original name %s 73181624Skmacy 74181624Skmacy# Freeze 75181624Skmacy0 string \037\237 frozen file 2.1 76181624Skmacy0 string \037\236 frozen file 1.0 (or gzip 0.5) 77181624Skmacy 78181624Skmacy# SCO compress -H (LZH) 79181624Skmacy0 string \037\240 SCO compress -H (LZH) data 80181624Skmacy 81181624Skmacy# European GSM 06.10 is a provisional standard for full-rate speech 82181624Skmacy# transcoding, prI-ETS 300 036, which uses RPE/LTP (residual pulse 83181624Skmacy# excitation/long term prediction) coding at 13 kbit/s. 84181624Skmacy# 85181624Skmacy# There's only a magic nibble (4 bits); that nibble repeats every 33 86181624Skmacy# bytes. This isn't suited for use, but maybe we can use it someday. 87181624Skmacy# 88181624Skmacy# This will cause very short GSM files to be declared as data and 89181624Skmacy# mismatches to be declared as data too! 90181624Skmacy#0 byte&0xF0 0xd0 data 91181624Skmacy#>33 byte&0xF0 0xd0 92181624Skmacy#>66 byte&0xF0 0xd0 93181624Skmacy#>99 byte&0xF0 0xd0 94181624Skmacy#>132 byte&0xF0 0xd0 GSM 06.10 compressed audio 95181624Skmacy 96181624Skmacy# bzip a block-sorting file compressor 97181624Skmacy# by Julian Seward <sewardj@cs.man.ac.uk> and others 98181624Skmacy# 99181624Skmacy0 string BZ bzip compressed data 100183375Skmacy>2 byte x \b, version: %c 101181624Skmacy>3 string =1 \b, compression block size 100k 102181624Skmacy>3 string =2 \b, compression block size 200k 103181624Skmacy>3 string =3 \b, compression block size 300k 104181624Skmacy>3 string =4 \b, compression block size 400k 105181624Skmacy>3 string =5 \b, compression block size 500k 106181624Skmacy>3 string =6 \b, compression block size 600k 107181624Skmacy>3 string =7 \b, compression block size 700k 108181624Skmacy>3 string =8 \b, compression block size 800k 109181624Skmacy>3 string =9 \b, compression block size 900k 110181624Skmacy 111181624Skmacy# lzop from <markus.oberhumer@jk.uni-linz.ac.at> 112181624Skmacy0 string \x89\x4c\x5a\x4f\x00\x0d\x0a\x1a\x0a lzop compressed data 113181624Skmacy>9 beshort <0x0940 114181624Skmacy>>9 byte&0xf0 =0x00 - version 0. 115181624Skmacy>>9 beshort&0x0fff x \b%03x, 116181624Skmacy>>13 byte 1 LZO1X-1, 117251767Sgibbs>>13 byte 2 LZO1X-1(15), 118251767Sgibbs>>13 byte 3 LZO1X-999, 119251767Sgibbs## >>22 bedate >0 last modified: %s, 120251767Sgibbs>>14 byte =0x00 os: MS-DOS 121251767Sgibbs>>14 byte =0x01 os: Amiga 122251767Sgibbs>>14 byte =0x02 os: VMS 123251767Sgibbs>>14 byte =0x03 os: Unix 124251767Sgibbs>>14 byte =0x05 os: Atari 125251767Sgibbs>>14 byte =0x06 os: OS/2 126251767Sgibbs>>14 byte =0x07 os: MacOS 127251767Sgibbs>>14 byte =0x0A os: Tops/20 128251767Sgibbs>>14 byte =0x0B os: WinNT 129251767Sgibbs>>14 byte =0x0E os: Win32 130251767Sgibbs>9 beshort >0x0939 131251767Sgibbs>>9 byte&0xf0 =0x00 - version 0. 132251767Sgibbs>>9 byte&0xf0 =0x10 - version 1. 133251767Sgibbs>>9 byte&0xf0 =0x20 - version 2. 134251767Sgibbs>>9 beshort&0x0fff x \b%03x, 135251767Sgibbs>>15 byte 1 LZO1X-1, 136251767Sgibbs>>15 byte 2 LZO1X-1(15), 137251767Sgibbs>>15 byte 3 LZO1X-999, 138251767Sgibbs## >>25 bedate >0 last modified: %s, 139251767Sgibbs>>17 byte =0x00 os: MS-DOS 140251767Sgibbs>>17 byte =0x01 os: Amiga 141251767Sgibbs>>17 byte =0x02 os: VMS 142251767Sgibbs>>17 byte =0x03 os: Unix 143251767Sgibbs>>17 byte =0x05 os: Atari 144251767Sgibbs>>17 byte =0x06 os: OS/2 145251767Sgibbs>>17 byte =0x07 os: MacOS 146251767Sgibbs>>17 byte =0x0A os: Tops/20 147251767Sgibbs>>17 byte =0x0B os: WinNT 148251767Sgibbs>>17 byte =0x0E os: Win32 149251767Sgibbs 150251767Sgibbs# 4.3BSD-Quasijarus Strong Compression 151251767Sgibbs# http://minnie.tuhs.org/Quasijarus/compress.html 152251767Sgibbs0 string \037\241 Quasijarus strong compressed data 153251767Sgibbs 154251767Sgibbs# From: Cory Dikkers <cdikkers@swbell.net> 155251767Sgibbs0 string XPKF Amiga xpkf.library compressed data 156251767Sgibbs0 string PP11 Power Packer 1.1 compressed data 157251767Sgibbs0 string PP20 Power Packer 2.0 compressed data, 158251767Sgibbs>4 belong 0x09090909 fast compression 159251767Sgibbs>4 belong 0x090A0A0A mediocre compression 160251767Sgibbs>4 belong 0x090A0B0B good compression 161251767Sgibbs>4 belong 0x090A0C0C very good compression 162251767Sgibbs>4 belong 0x090A0C0D best compression 163251767Sgibbs 164251767Sgibbs# 7z archiver, from Thomas Klausner (wiz@danbala.tuwien.ac.at) 165251767Sgibbs# http://www.7-zip.org or DOC/7zFormat.txt 166251767Sgibbs# 167251767Sgibbs0 string 7z\274\257\047\034 7z archive data, 168251767Sgibbs>6 byte x version %d 169251767Sgibbs>7 byte x \b.%d 170251767Sgibbs 171251767Sgibbs# AFX compressed files (Wolfram Kleff) 172251767Sgibbs2 string -afx- AFX compressed file data 173251767Sgibbs