Many PS2 discs contain large amounts of empty "padding" or "junk" data used to fill the outer edges of the physical disc for faster reading. Removing this alone can often drop a 4GB ISO down to under 1GB without losing any game content.
Highly compressed games may occasionally crash during cutscenes if those files were improperly stripped. ps2 iso highly compressed under 100mb patched
This is where the real size reduction happens. To get under 100MB, rippers often remove (or "rip") high-quality FMV (Full Motion Video) cutscenes, background music, or dialogue audio. Many PS2 discs contain large amounts of empty