2 unstable releases
Uses old Rust 2015
0.2.0 | Feb 17, 2018 |
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0.1.0 | Feb 17, 2018 |
#685 in Compression
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27KB
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sega_cmp
This Rust crate provides an implementation of Sega's CMP run-length encoding compression format. This format was created by Sega, and used in many Saturn games by Sega and third parties. This library aims to provide a 100%-compatible compressor able to be used to replace data in retail Saturn games.
This crate embeds C code written by @MrConan1.
Contributing
- Fork the repository
- Create a new branch
- Commit your changes
- Open a pull request
- 🎉
Bugs and support
Please report any issues on this repository's issue tracker. I'll try to do whatever I can to help!
lib.rs
:
This crate provides support for compressing files using Sega's CMP run-length encoding scheme, which was used in games for the Sega Saturn game console.
Run-length encoding is a simple kind of compression which works by analyzing data for repetitive sequences of data (or "runs"); any repeating sequences can be replaced by commands to repeat X data N times.
For example, imagine the text AAAAAAAABBBBAABA
.
If you described it in terms of patterns, you could think of it as being
8A4B2A1B1A
- which takes up 10 bytes instead of 16.
Sega included CMP in the official Saturn SDK; they provided a closed-source commandline tool to compress data and source code to do compression from within games. As a result, many games used it for data with lots of repetitive content such as text and graphics. This crate's CMP implementation aims to be 100% compatible with the original decoder; it produces identical compressed data to the original encoder. Its output has been tested to work in commercial Saturn games which use CMP.
This crate provides two basic functions: the header-generating create_header
,
and the data-creating compress
. Most Saturn games store both in the same place,
with the header followed immedaitely by the compressed data.
Dependencies
~225KB