# zstdmt

**Repository Path**: mirrors_mcmilk/zstdmt

## Basic Information

- **Project Name**: zstdmt
- **Description**: Multithreading Library for Brotli, Lizard, LZ4, LZ5, Snappy and Zstandard
- **Primary Language**: Unknown
- **License**: BSD-2-Clause
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-09-25
- **Last Updated**: 2026-10-11

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README


# 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

- the frame header for [Lizard], [LZ4], [LZ5] and [Zstandard] is like this:

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
- see [programs](https://github.com/mcmilk/zstdmt/tree/master/programs)

## Usage of the Library

- see [lib](https://github.com/mcmilk/zstdmt/tree/master/lib)

[Brotli]:https://github.com/google/brotli/
[LZ4]:https://github.com/lz4/lz4/
[LZ5]:https://github.com/inikep/lz5/
[Zstandard]:https://github.com/facebook/zstd/
[Lizard]:https://github.com/inikep/lizard/
[Snappy-c]:https://github.com/andikleen/snappy-c
[LZFSE]:https://github.com/lzfse/lzfse

/TR 2020-10-15