Armadillo compression algorithms
 

Does anybody know what older versions of Armadillo used as their compression algorithm?
I know newer versions (3.10+) use either ZLIB, or just a simple RLE-like packing ("method 0").
Older versions (e.g. Armadillo 2.x), however, use 3 different methods (according to the compression setting you select in the program) - the same "method 0", and more complex methods 1 and 2 (especially method 2 is quite a lot of code). Does anybody know what they are? Is it some common compression algorithm, with source code available maybe?

Thanks!

I've never done any reversing of armadillo's compression algorithms myself, I've always just got the armadillo rtl to do all the unpacking for me, and not worried about it. I suspect most other people have gone down the same path.

Is there some reason your looking for this info, rather than just using the built in functions?

Well, yes, I'd like to have a portable source that unpacks the streams (compilable on non-Intel platforms, with thorough bounds checks, etc.) :)