Gzip
From Just Solve the File Format Problem
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* [[Wikipedia:gzip|Wikipedia article]] | * [[Wikipedia:gzip|Wikipedia article]] | ||
* [http://www.infinitepartitions.com/cgi-bin/showarticle.cgi?article=art001 Dissecting the GZIP format] | * [http://www.infinitepartitions.com/cgi-bin/showarticle.cgi?article=art001 Dissecting the GZIP format] | ||
+ | * [https://twitter.com/angealbertini/status/534817626342436864/photo/1 Chart of format] |
Revision as of 00:45, 19 November 2014
gzip is a compressed file format and command line utility used primarily on Unix-style operating systems, but available cross-platform. It uses DEFLATE compression.
Contents |
Identification
gzip files begin with two signature bytes: 0x1F 0x8B
. The third byte indicates the compression method, and is normally 0x08
(meaning DEFLATE).
gzip 0.5 apparently used Freeze/Melt 1.x format, with signature bytes 0x1F 0x9E
.
Specifications
Software
- Original gzip
- GNU gzip
- 7-Zip
- zlib
- zopfli (Gzip-compatible, better compression, but very slow compression)