Compression algorithms employed in MPQs?

[XTZGZoReX]

After lurking around and checking stormlib/libmpq, it doesn't seem that there's any info anywhere on what compression algorithms are currently in use for WoW's MPQ files.

Does anyone have a clue? I know the MPQ format supports ~6 different algorithms, but I'm fairly sure they aren't all used in WoW...

[namreeb]

There is quite a bit of information about the MPQ format on the StormLib site. MPQ Archives - Overview

[XTZGZoReX]

Yeah, I already checked that. Unfortunately, no info on what's currently employed.

I guess I can just implement everything, though it's gonna take some time. (I'm writing an MPQ library in pure C#; no P/Invoke or similar platform-dependent tricks.)

So far, I've found these C# libraries that'll probably be helpful:

.NET Zip Library #ziplib (SharpZipLib) (covers zlib, bzip2)
LZMA SDK (Software Development Kit) (covers lzma)

I still need libraries for sparse, ima adpcm, and huffman, though.

EDIT: Seems like SharpZipLib handles huffman.

[_Mike]

Have a look at mpqtool - Project Hosting on Google Code for examples on adpcm and huffman decompression.
It doesn't do lzma or sparse, but last time I checked* wow didn't use those.


*) about a year ago, so things might have changed by now.

[amadmonk]

WR, it's not like the state of the art in compression algorithms has changed much in the past few years.

[XTZGZoReX]

If sparse isn't actually used, I guess I can just steal the decompression algorithms from mpqtool.

Thanks.