Originally created for the MAME (arcade) emulation project, CHD uses advanced, modern compression algorithms (like LZMA and Zstandard). It treats data as distinct blocks or "hunks," optimizing how files are compressed and read. 1. Drastic Storage Savings Without Performance Loss
Sourcing files directly from the Internet Archive —or converting your existing library using CHDMAN—gives you the best of both worlds. You get lightning-fast downloads, clean library organization, maximum storage space on your SD cards, and flawless emulation performance. It is the definitive, future-proof way to experience the legendary PlayStation Portable library. If you want to optimize your library further, let me know:
Massive file sizes. A game that only uses 200MB of actual data will still take up a full 1.6GB on your hard drive if the rest of the disc is filled with dummy data. 2. CSO (Compressed ISO)
To understand why CHD reigns supreme, we must look at how it compares to its predecessors in terms of storage efficiency and data integrity.
When searching for full game sets, look for terms like "PSP Redump CHD" or "PSP CHD Collection." However, note that due to the space savings, some uploaders are actively archiving full Redump libraries using CHD to preserve hard drive space for users.
Recommendations for Improving PSP CHD Collections on the Internet Archive
CHD, originally developed by the MAME team for arcade disc preservation, uses modern, highly sophisticated compression routines (like LZMA and Zstandard). offers 0% compression, resulting in massive files.
Replace game.iso with the name of your input file and game.chd with your desired output name.