If you are exclusively playing on PPSSPP (Android, Windows, iOS) or a PSP with custom firmware (via Inferno driver), use ZSO . If you are archiving PS2 games, use CHD . Never use plain ISO.
The app will create the ZSO file in the same folder as the original ISO. You can then delete the original ISO. iso to zso converter
Unlike ZIP or CSO (another PSP compression format), ZSO loads levels and cutscenes almost as fast as raw ISO. In PPSSPP, God of War: Chains of Olympus ran with no stuttering or audio crackling. That’s the magic of ZSO’s block-based compression. If you are exclusively playing on PPSSPP (Android,