Gakuen K .pak files help

[Crystal2002]

Hello, I've been trying to crack the .pak files in the PSP (not Vita) version of Gakuen K -Wonderful School Days- (here's a VNDB link of it) and have been getting no luck with it. The .pak files are BGM.pak, Data.pak (Which has bgcmn.dat, thanks HxD, and probably another .dat or two with the character sprites and UI elements), and Voice.pak. I've tried going through Noesis, PakUnpacker, Crage, and Arc Unpacker to try and extract them, but with no luck. Would anyone know/have ideas on how to extract the assets, outside of ripping during gameplay?

Any help would be much appreciated, good luck and thank you!

P.S.- Here's a copy of the BGM.pak and Data.pak

[puggsoy]

DATA.PAK is simply a ZIP file, from which you can extract BGCMN.DAT_. This can be extracted using this QuickBMS script:

Code:

# Gakuen K -Wonderful School Days- .DAT_ format
#
# Written by puggsoy
# script for QuickBMS http://quickbms.aluigi.org

idstring "DAT "
get FILES long

for i = 0 < FILES
   getdstring NAME 0x20
   get SIZE long
   get OFFSET long

   log NAME OFFSET SIZE
next i

This extracts a few .DAT files (which just seem to contain some generic data), and a whole lot of .gim files. The latter can be converted with Noesis.

BGM.PAK is just a bunch of .wav files stuck together (with padding between them). I can extract them but they seem to be corrupted or something since they don't seem to play any sound, and also tend to crash File Explorer :\ If you want to try it yourself though, here's a script for it:

Code:

# Gakuen K -Wonderful School Days- BGM.PAK format
#
# Written by puggsoy
# script for QuickBMS http://quickbms.aluigi.org

for i = 0 < 9999999
   findloc OFF string RIFF
   goto OFF
   goto 4 0 SEEK_CUR
   get LEN long
   math LEN += 8
   set NAME ""
   string NAME += i
   string NAME += ".wav"
   log NAME OFF LEN
   math OFF += LEN
   goto OFF
next i

[Crystal2002]

Thanks a bunch, Puggsoy! It probably is best to assume that the .wav files are corrupted, and I was able to get all the extra background elements. It does make me wonder where the main-game elements are, such as the character sprites, the UI stuff, and the main backgrounds of the school... That's definitely something I'll look more into

Once again, thank you for your help! It really helped shed some light on how the game was packed!