Pucrunch decompressor for Z80

by ccfg on 11-07-2004, 00:27
Topic: Software
Tags: Utilities
Languages:

Jussi Pitkänen (ccfg) has ported the Pucrunch decompressor to Z80. You can read more about it at his homepage.

Relevant link: Pucrunch decompressor for Z80

Comments (7)

By anonymous

incognito ergo sum (118)

anonymous's picture

12-07-2004, 01:52

Cool Smile
I asked ccfg on #msxdev @ Rizon to do the FIRE.G9B compression 'test', as used in this forum thread: http://www.msx.org/forumtopic1900.html

The result was 114518 bytes, which is even smaller than TCF, and comes incredibly close to RAR and ZIP! So obviously this cruncher is very potent.

Now all left to analyze is the decompression speed. But it's already obvious this thing should be great for decompressing non-realtime stuff.

By [WYZ]

Champion (423)

[WYZ]'s picture

13-07-2004, 09:16

Somebody tried this decompressor ASM code in MSX? I did it but it seems to work uncorrectly. (compressing files with -c0 -d options)

By ccfg

Rookie (20)

ccfg's picture

13-07-2004, 17:47

That's weird because I tested it with many programs (and other data) and it never failed. I'm curious about this possible bug, so it would be nice if you could give some more information (or even send the code to me).

By flyguille

Prophet (3028)

flyguille's picture

14-07-2004, 17:49

So, What? got a bug or not?

I are interested in this develop.... overall because i are looking for an official compresor/decompresor for MNBIOS....

And i got several questions:

This one, need to read/write ramdomly the compress file / uncompress file. Or just need the LAST xxxx bytes readed (secuential working)?

And what is the compress factor?

By anonymous

incognito ergo sum (118)

anonymous's picture

14-07-2004, 20:22

compression factor depends on two things:
1. the source file
2. the quality of the compressor

If you want to create a MSX version of this compressor, you will have a lot of trouble making the compression factor identical to the PC version. Or, the compressor will run EXTREMELY slow.

It's all about RAM. These compressors use several megabytes RAM for buffers, hash tables and other stuff.

By [WYZ]

Champion (423)

[WYZ]'s picture

15-07-2004, 00:11

ccfg said :

"This version of the decompressor is self-modifying code. If you are
trying to run it from ROM, it will fail"

so it was not a bug...

By ccfg

Rookie (20)

ccfg's picture

15-07-2004, 01:10

Ah, good!

It should be quite easy to make a workaround for your ROM game (modify it to run from ROM or relocate it first to RAM and then run it).

About that quote: "This version of the decompressor is self-modifying code. If you are
trying to run it from ROM, it will fail"

It was the author of Pucrunch who said that, NOT me (I just ported the decompressor) ... just to make it clear.