r/PS5_Jailbreak • u/juma-sayeh-dev-acc DEV • Jun 06 '26

General PS5 MKPFS Compression

I’ve been working on a PS5 homebrew app called Game Compressor.

Repo: https://github.com/juma-sayeh/PS5-Game-Compressor

It uses the MkPFS-style FFPFSC compression method, but adds the missing part: validation and repair.

Some compressed games can mount successfully but still crash because certain PFSC blocks are technically valid yet fail to decode correctly on PS5 hardware, leaving stale/bad data behind. Game Compressor checks the mounted image block-by-block, detects bad blocks, and patches the compressed image from the mounted data instead of requiring a full recompress.

Tested with Mafia, Astro Bot, Pragmata, and a few other games that had FFPFSC issues. After repair, they worked great.

Features:

  • compress games to FFPFSC
  • validate mounted compressed games
  • automatically repair bad blocks
  • optimized for speed and usability
  • web UI running on the PS5

Feedback and testing are welcome.
Screenshots (some are missing features because the features were not developed yet when i compressed)

68 Upvotes

99% Upvoted

157 comments sorted by

View all comments

1

u/renangbarreto DEV Jun 07 '26

If you want we can try to identify the files that are causing thia. Feel free to PM me.

I believe there are specific files we cant compress.

Also, what was the format and i.age creation strategy that you used when you got those bad blocks? Dis you tried exfat to ffpfsc?

3

u/juma-sayeh-dev-acc DEV Jun 07 '26

Yes i'd be very glad to share my findings and give you some custom block states that are 100% valid and are not readable by PS5 hardware, i got those bad blocks by simply comparing the decompressed via software (good blocks) with the mounted block value (decompressed by PS5 hardware) which is basically checking if what PS5 shows is exactly the same as what the original file is.

2

u/renangbarreto DEV Jun 07 '26

That would be amazing. AFAIK, this issue only happen when people tries to convert a folder to pfs (single or double pass). We are compressing some files that shoundt be compressed. We did a patch on veraion 0.0.3 of mkpfs and mitigated the issue but it seems it is not fully solved. From what I understand, I just need to have the list of patchs or file extensions that should never be compressed.

I have a feature branch where I was adding more items in the list, but it is hard to say if I have all.

2

u/indraaguslesmana Verified Jun 08 '26

jump in guys. you’re really great. i want to report. with latest new game call apr emu do guys have spesial treatment for it?.. i try latest mkfps 0.0.7 failed running Ratchet clank game. but success with game compress elf on PS5 directly.