The .pac archive format used in the visual novel "SHUFFLE!" (シャッフル!) is really simple and doesn't even need to be reverse engineered. It just has a file index at the beginning, which specifies each filename, position in the archive and the filesize. I wrote a small program that extracts all the files in the .pac packages into the sub-folder "extract" and I thought it could useful for others, so I share it in this post. One of the really interesting things is that you can delete the .pac files if you move the extracted folders into the game directory. The game then reads the data from the extracted files inside the directories.



If you want to convert the images from the GPD-format into png, you can use my image converter for the GPD images used by SHUFFLE! or if you want to only look at them you can use my GPD viewer.

8 Responses to “An unpacker for the .pac archive files used by SHUFFLE!”

  1. Sam
    June 6th, 2013 at 00:34

    Very cool tanks……

  2. Michal
    October 29th, 2013 at 10:00

    Hello, I downloaded the program but I got into a problem, It opens, and then instantly closes, I cant do anything, tried to download it few times with different browsers, but it didn’t worked either. Can you help me pls!! Pls contact me.

  3. thomas singh
    November 17th, 2013 at 14:39

    just right click on it and select “run as administrator” if u r using windows 7..

  4. Sayantan Roychowdhury
    June 25th, 2014 at 15:20

    sir, I have kept the exe file on desktop. Even after right clicking and selecting to run it as administrator, the command window just appears and then disappears. I have windows 7. please help me.

  5. Moritz
    June 25th, 2014 at 16:39

    The unpacker only works when it is in the same directory as the pac files.

  6. Sayantan Roychowdhury
    June 28th, 2014 at 08:40

    Sir I placed the files in the same folder but it showed errors while unpacking. thanks for your response though.

  7. Anonymous
    October 19th, 2018 at 07:03

    i tried running as administrator and all that shit but it just closes itself

  8. nyanpan
    November 28th, 2019 at 20:30

    So what do we do to recompile .pac files? I extracted a scenario from LUNE type games called srp.pac and well it had a bunch of srp files in it. Can I just recompile it into anything? and just rename the extension as .pac?

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