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README.md

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Multithreading Library for Brotli, Lizard, LZ4, LZ5, Snappy-c, LZFSE and Zstandard

Description

  • works with skippables frame id 0x184D2A50 (12 bytes per compressed frame)
  • brotli is supported the same way, it will encapsulate the real brotli stream within an 16 byte frame header

Generic skippable frame definition

size value description
4 bytes 0x184D2A50U magic for skippable frame
4 bytes 4 size of skippable frame
4 bytes compressed size size of the following frame (compressed data)

Brotli frame definition

  • the frame header for brotli is defined a bit different:
size value description
4 bytes 0x184D2A50U magic for skippable frame (like zstd)
4 bytes 8 size of skippable frame
4 bytes compressed size size of the following frame (compressed data)
2 bytes 0x5242U magic for brotli "BR"
2 bytes uncompressed size allocation hint for decompressor (64KB * this size)

Snappy-c frame definition

  • the frame header for Snappy-c is defined a bit different:
size value description
4 bytes 0x184D2A50U magic for skippable frame (like zstd)
4 bytes 8 size of skippable frame
4 bytes compressed size size of the following frame (compressed data)
2 bytes 0x5053U magic for Snappy-c "SP"
2 bytes uncompressed size allocation hint for decompressor (64KB * this size)

LZFSE frame definition

  • the frame header for Lzfse is defined a bit different:
size value description
4 bytes 0x184D2A50U magic for skippable frame (like zstd)
4 bytes 8 size of skippable frame
4 bytes compressed size size of the following frame (compressed data)
2 bytes 0x464CU magic for Lzfse "LF"
2 bytes uncompressed size allocation hint for decompressor (64KB * this size)

Usage of the Testutils

Usage of the Library

/TR 2020-10-15