Ripping files from PS2 .isos

[eldomtom2]

I would like to rip audio files etc. from .isos of some PS2 games. However, the .isos appear to use methods of storing files I can't find info on.

• The first type has the majority of disk space used by four files: null.1g, null.2g, CDROM.fpd, and SOUND.fpd. I presume most of the game's data is in these files, but I can't find anything on how to extract them.
  
• The second type has the majority of disk space used by DATA.MF and a "DSJ" file containing a number of .dsj files. It also stores the game's FMVs as .pss files, which I can play but without audio (do .pss files contian audio?).
  

Hopefully someone here knows something about these file types and how to extract them.