Gzip
From Just Solve the File Format Problem
(Difference between revisions)
MihaiPopa7 (Talk | contribs) (→Specifications) |
Parchivist (Talk | contribs) |
||
Line 36: | Line 36: | ||
* [https://twitter.com/angealbertini/status/534817626342436864/photo/1 Chart of format] | * [https://twitter.com/angealbertini/status/534817626342436864/photo/1 Chart of format] | ||
* [https://stackoverflow.com/questions/20762094/how-are-zlib-gzip-and-zip-related-what-do-they-have-in-common-and-how-are-they/20765054#20765054 How are zlib, gzip and Zip related? What do they have in common and how are they different?] - Response to StackOverflow question by zlib/gzip co-creator Mark Adler | * [https://stackoverflow.com/questions/20762094/how-are-zlib-gzip-and-zip-related-what-do-they-have-in-common-and-how-are-they/20765054#20765054 How are zlib, gzip and Zip related? What do they have in common and how are they different?] - Response to StackOverflow question by zlib/gzip co-creator Mark Adler | ||
+ | * [[GZSteg]] - hiding a file within a gzip |
Revision as of 15:46, 9 November 2023
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
Sample files
Software
- Original gzip
- GNU gzip
- 7-Zip
- zlib
- zopfli (Gzip-compatible, better compression, but very slow compression)
- Tiny gzip decompressor without using zlib (C++)
- Deark
See also DEFLATE#Software.
Links
- Wikipedia article
- Dissecting the GZIP format
- Chart of format
- How are zlib, gzip and Zip related? What do they have in common and how are they different? - Response to StackOverflow question by zlib/gzip co-creator Mark Adler
- GZSteg - hiding a file within a gzip