In-game FMV (Full Motion Video) cutscenes, background music tracks, uncompressed audio, and multiplayer maps.
When you load a .chd or .cso file, the decompresses the required data on-the-fly, allowing the game to play exactly as if it were a full-sized ISO. You do not need to extract the files first, which saves both time and additional storage space [1]. Advantages of Using Highly Compressed Games
Open PCSX2, click System > Boot ISO (Fast) or Boot ISO (Full) . If the game hangs on a black screen, the compression format may be unsupported or corrupted.
PCSX2 Compressed Games: Efficiency and Best Formats Modern versions of