CHD (Compressed Hunks of Data) is a lossless compression format originally developed for MAME (Multiple Arcade Machine Emulator) to compress CD-ROM images of arcade games. It later gained support in other emulators, including those for PlayStation (PSX/PS1).
The CHD format uses LZMA and FLAC (for CD audio). Both are lossless. When the PSX community moved to CHD in 2021, archivists worried about "lossy transitions." However, hashing a CHD extracted back to BIN/CUE yields a bit-perfect copy of the original. Major ROM managers like Clrmamepro and RomVault added CHD support by 2021, allowing users to rebuild full Redump sets in CHD format without data loss. chd psx roms 2021
.pbp was popular for PSP emulation (POPS), but CHD overtook it by 2020–2021 because of better compression ratios, lossless audio, and broader emulator adoption. Obtain the CHD file(s) and any required descriptor files
CHD PSX ROMs 2021 Collection
No File Clutter: Consolidates multiple track .bin files and a .cue sheet into one tidy .chd file. Where to Find CHD PSX ROMs in 2021
This is a legal gray area. If you own the original discs, creating CHD files from your personal rips is legal (in most jurisdictions). However, downloading pre-converted sets is technically piracy.
If you’d like a practical guide (commands, batch scripts, or verifying CHD integrity), let me know.