What is a .CSO file?
CSO (CISO) is a compressed disc image, popular for PSP games.
- Did you know
- CSO shrinks a game ISO so more titles fit on a memory card.
- CSO, also called CISO, was built to shrink ripped PSP UMD games so more titles fit on a memory card.
- Its lossless compression typically saves twenty to fifty per cent, and higher levels trade smaller files for slower decompression.
- What Analyser reads
- Identify and read more game and emulator files: Unity asset bundles, Unreal cooked assets, CISO/CHD disc images, FMOD/Wwise sound banks, Spine skeletons and atlases, GameMaker/LDtk/TIC-80 projects, Minecraft Anvil regions, Warcraft III maps, Ren Py and RPG Maker data, extra console ROMs (Atari, PC Engine, Master System/Game Gear, WonderSwan, 3DS homebrew), xdelta/Basis patches and emulator saves and movies.
- Depth of analysis
- .CSO is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .CSO file
- Drag a .CSO file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.