https://github.com/emmanuel-marty/lz4ultra

Optimal LZ4 compressor, that produces files that decompress faster while keeping the best compression ratio
https://github.com/emmanuel-marty/lz4ultra

c compression lz4 optimization suffixarray

Last synced: about 1 month ago
JSON representation

Optimal LZ4 compressor, that produces files that decompress faster while keeping the best compression ratio

• Host: GitHub
• URL: https://github.com/emmanuel-marty/lz4ultra
• Owner: emmanuel-marty
• License: other
• Created: 2019-04-08T21:24:07.000Z (about 6 years ago)
• Default Branch: master
• Last Pushed: 2023-01-29T09:38:41.000Z (over 2 years ago)
• Last Synced: 2025-04-09T10:34:02.702Z (2 months ago)
• Topics: c, compression, lz4, optimization, suffixarray
• Language: C
• Size: 199 KB
• Stars: 58
• Watchers: 9
• Forks: 5
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• AwesomeCppGameDev - lz4ultra

README

        
lz4ultra -- Optimal LZ4 packer with faster decompression

========================================================

lz4ultra is a command-line optimal compression utility that produces compressed files in the [lz4](https://github.com/lz4/lz4) format created by Yann Collet.

The tool creates optimally compressed files, like lz4 in optimal compression mode ("lz4hc"), smallLZ4, blz4 and lz4x.

With enwik9 (1,000,000,000 bytes):

                                      Compr.size    Tokens      Decomp.time (μs, Core i7-6700)

    lz4 1.9.2 -12 (favor ratio)       372,443,347   95,698,349  505,804

    smalLZ4 1.5 -9                    371,680,328   93,172,985  348,018

    lz4ultra 1.3.0 (favor ratio)      371,680,323   93,165,899  347,936

    lz4 1.9.2 -12 --favor-decSpeed    377,175,400   92,080,802  457,141

    lz4ultra 1.3.0 --favor-decSpeed   376,118,079   88,521,993  296,972

The produced files are meant to be decompressed with the lz4 tool and library. While lz4ultra includes a decompressor, it is mostly meant to verify the output of the compressor and isn't as optimized as Yann Collet's lz4 proper.

The tool defaults to 4 Mb blocks with inter-block dependencies but can be configured to output all of the LZ4 block sizes (64 Kb to 4 Mb), to use the LZ4 8 Mb blocks legacy encoding, and to compress independent blocks, using command-line switches.

lz4ultra is developed by Emmanuel Marty with the help of spke.