Roudoudou worked on a compressor / decompressor which uses the LZ48 / LZ49 compression algorithm on the Amstrad CPC and released his work in the CPCWiki forums. The compressor is inspired by the LZ4 compression algorithm of Yann Collet and the modifications fits well to the Z80 CPU of the Amstrad CPC. The advantage of this compression method is, that the decompression code is very small (83 bytes) and very fast. The disadvatage is that there are other compressors which feature a better compression ratio, but require more memory and more time for decompression as well.
You can get more information about the modified algorithm and download the assembly source from the CPCWiki forums. You can also find a version for SDCC / CPCtelera and binary files for Windows there.

LZ48/49 (de)compressor
LZ48-49-de-compressor.zip

16.5 KiB
387 Downloads
Details

This archive features the LZ48/LZ49 (de)compression routines by Roudoudou, which were derived from the LZ4 compression by Yann Collet. Its advantage is the small decompression routine size (84 bytes) and high decompression speed. In this archive you will also find Windows binaries of the compressor for cross-development and routines, which you can direclty use with SDCC / CPCtelera.

Author:	Roudoudou
Platforms:	Amstrad CPC
Category:	Programming
License:	Freeware
Date:	December 31, 2016