compress 5.8 KB

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  1. #------------------------------------------------------------------------------
  2. # compress: file(1) magic for pure-compression formats (no archives)
  3. #
  4. # compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, etc.
  5. #
  6. # Formats for various forms of compressed data
  7. # Formats for "compress" proper have been moved into "compress.c",
  8. # because it tries to uncompress it to figure out what's inside.
  9. # standard unix compress
  10. 0 string \037\235 compress'd data
  11. >2 byte&0x80 >0 block compressed
  12. >2 byte&0x1f x %d bits
  13. # gzip (GNU zip, not to be confused with Info-ZIP or PKWARE zip archiver)
  14. # Edited by Chris Chittleborough <cchittleborough@yahoo.com.au>, March 2002
  15. # * Original filename is only at offset 10 if "extra field" absent
  16. # * Produce shorter output - notably, only report compression methods
  17. # other than 8 ("deflate", the only method defined in RFC 1952).
  18. 0 string \037\213 gzip compressed data
  19. >2 byte <8 \b, reserved method
  20. >2 byte >8 \b, unknown method
  21. >3 byte &0x01 \b, ASCII
  22. >3 byte &0x02 \b, continuation
  23. >3 byte &0x04 \b, extra field
  24. >3 byte&0xC =0x08
  25. >>10 string x \b, was "%s"
  26. >9 byte =0x00 \b, from MS-DOS
  27. >9 byte =0x01 \b, from Amiga
  28. >9 byte =0x02 \b, from VMS
  29. >9 byte =0x03 \b, from Unix
  30. >9 byte =0x05 \b, from Atari
  31. >9 byte =0x06 \b, from OS/2
  32. >9 byte =0x07 \b, from MacOS
  33. >9 byte =0x0A \b, from Tops/20
  34. >9 byte =0x0B \b, from Win/32
  35. >3 byte &0x10 \b, comment
  36. >3 byte &0x20 \b, encrypted
  37. ### >4 ledate x last modified: %s,
  38. >8 byte 2 \b, max compression
  39. >8 byte 4 \b, max speed
  40. # packed data, Huffman (minimum redundancy) codes on a byte-by-byte basis
  41. 0 string \037\036 packed data
  42. >2 belong >1 \b, %d characters originally
  43. >2 belong =1 \b, %d character originally
  44. #
  45. # This magic number is byte-order-independent.
  46. 0 short 0x1f1f old packed data
  47. # XXX - why *two* entries for "compacted data", one of which is
  48. # byte-order independent, and one of which is byte-order dependent?
  49. #
  50. 0 short 0x1fff compacted data
  51. # This string is valid for SunOS (BE) and a matching "short" is listed
  52. # in the Ultrix (LE) magic file.
  53. 0 string \377\037 compacted data
  54. 0 short 0145405 huf output
  55. # bzip2
  56. 0 string BZh bzip2 compressed data
  57. >3 byte >47 \b, block size = %c00k
  58. # squeeze and crunch
  59. # Michael Haardt <michael@cantor.informatik.rwth-aachen.de>
  60. 0 beshort 0x76FF squeezed data,
  61. >4 string x original name %s
  62. 0 beshort 0x76FE crunched data,
  63. >2 string x original name %s
  64. 0 beshort 0x76FD LZH compressed data,
  65. >2 string x original name %s
  66. # Freeze
  67. 0 string \037\237 frozen file 2.1
  68. 0 string \037\236 frozen file 1.0 (or gzip 0.5)
  69. # SCO compress -H (LZH)
  70. 0 string \037\240 SCO compress -H (LZH) data
  71. # European GSM 06.10 is a provisional standard for full-rate speech
  72. # transcoding, prI-ETS 300 036, which uses RPE/LTP (residual pulse
  73. # excitation/long term prediction) coding at 13 kbit/s.
  74. #
  75. # There's only a magic nibble (4 bits); that nibble repeats every 33
  76. # bytes. This isn't suited for use, but maybe we can use it someday.
  77. #
  78. # This will cause very short GSM files to be declared as data and
  79. # mismatches to be declared as data too!
  80. #0 byte&0xF0 0xd0 data
  81. #>33 byte&0xF0 0xd0
  82. #>66 byte&0xF0 0xd0
  83. #>99 byte&0xF0 0xd0
  84. #>132 byte&0xF0 0xd0 GSM 06.10 compressed audio
  85. # bzip a block-sorting file compressor
  86. # by Julian Seward <sewardj@cs.man.ac.uk> and others
  87. # Disabled because it is too weak (MPi)
  88. #0 string BZ bzip compressed data
  89. #>2 byte x \b, version: %c
  90. #>3 string =1 \b, compression block size 100k
  91. #>3 string =2 \b, compression block size 200k
  92. #>3 string =3 \b, compression block size 300k
  93. #>3 string =4 \b, compression block size 400k
  94. #>3 string =5 \b, compression block size 500k
  95. #>3 string =6 \b, compression block size 600k
  96. #>3 string =7 \b, compression block size 700k
  97. #>3 string =8 \b, compression block size 800k
  98. #>3 string =9 \b, compression block size 900k
  99. # lzop from <markus.oberhumer@jk.uni-linz.ac.at>
  100. 0 string \x89\x4c\x5a\x4f\x00\x0d\x0a\x1a\x0a lzop compressed data
  101. >9 beshort <0x0940
  102. >>9 byte&0xf0 =0x00 - version 0.
  103. >>9 beshort&0x0fff x \b%03x,
  104. >>13 byte 1 LZO1X-1,
  105. >>13 byte 2 LZO1X-1(15),
  106. >>13 byte 3 LZO1X-999,
  107. ## >>22 bedate >0 last modified: %s,
  108. >>14 byte =0x00 os: MS-DOS
  109. >>14 byte =0x01 os: Amiga
  110. >>14 byte =0x02 os: VMS
  111. >>14 byte =0x03 os: Unix
  112. >>14 byte =0x05 os: Atari
  113. >>14 byte =0x06 os: OS/2
  114. >>14 byte =0x07 os: MacOS
  115. >>14 byte =0x0A os: Tops/20
  116. >>14 byte =0x0B os: WinNT
  117. >>14 byte =0x0E os: Win32
  118. >9 beshort >0x0939
  119. >>9 byte&0xf0 =0x00 - version 0.
  120. >>9 byte&0xf0 =0x10 - version 1.
  121. >>9 byte&0xf0 =0x20 - version 2.
  122. >>9 beshort&0x0fff x \b%03x,
  123. >>15 byte 1 LZO1X-1,
  124. >>15 byte 2 LZO1X-1(15),
  125. >>15 byte 3 LZO1X-999,
  126. ## >>25 bedate >0 last modified: %s,
  127. >>17 byte =0x00 os: MS-DOS
  128. >>17 byte =0x01 os: Amiga
  129. >>17 byte =0x02 os: VMS
  130. >>17 byte =0x03 os: Unix
  131. >>17 byte =0x05 os: Atari
  132. >>17 byte =0x06 os: OS/2
  133. >>17 byte =0x07 os: MacOS
  134. >>17 byte =0x0A os: Tops/20
  135. >>17 byte =0x0B os: WinNT
  136. >>17 byte =0x0E os: Win32
  137. # 4.3BSD-Quasijarus Strong Compression
  138. # http://minnie.tuhs.org/Quasijarus/compress.html
  139. 0 string \037\241 Quasijarus strong compressed data
  140. # From: Cory Dikkers <cdikkers@swbell.net>
  141. 0 string XPKF Amiga xpkf.library compressed data
  142. 0 string PP11 Power Packer 1.1 compressed data
  143. 0 string PP20 Power Packer 2.0 compressed data,
  144. >4 belong 0x09090909 fast compression
  145. >4 belong 0x090A0A0A mediocre compression
  146. >4 belong 0x090A0B0B good compression
  147. >4 belong 0x090A0C0C very good compression
  148. >4 belong 0x090A0C0D best compression
  149. # 7-zip archiver, from Thomas Klausner (wiz@danbala.tuwien.ac.at)
  150. # http://www.7-zip.org or DOC/7zFormat.txt
  151. #
  152. 0 string 7z\274\257\047\034 7-zip archive data,
  153. >6 byte x version %d
  154. >7 byte x \b.%d
  155. # AFX compressed files (Wolfram Kleff)
  156. 2 string -afx- AFX compressed file data