GoodMerge Compression Error

Discussion in 'Wii - Emulation and Homebrew' started by Devante, Aug 4, 2012.

  1. Devante
    OP

    Devante Crescent fresh at best.

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    Just got 8 GB worth of goodmerged GBA games only to find that VBAGX won't load them because "dictionary size too large" when trying to decompress.

    Does anyone know the maximum size of the dictionary that VBAGX can handle?
    Does anyone know of a way to 'convert' the 7z sets I have now to this new compression setting? Or will I have to unzip everything and start from scratch?

    I also hope that with answers, this thread will show others what they need to know as I haven't found much by searching.

    I'll update this top post with any useful settings/answers.

    Thanks!

    By the way, one useful tidbit I found in another thread from a while ago:
     
  2. PsyBlade

    PsyBlade Snake Charmer

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    I don't think that there is a way to directly recompress
    but it might be possible to decompress to a pipe or memory and then compress from there

    "man 7za" gives:

    -t7z
    7z archive

    -m0=lzma
    lzma method

    -mx=9
    level of compression = 9 (Ultra)

    -mfb=64
    number of fast bytes for LZMA = 64

    -md=32m
    dictionary size = 32 megabytes

    ms=on
    solid archive = on


    edit:
    pipe does not work nice with multiple files inside the archive
    but /dev/shm works fine
    in the directory with the files run:

    find . -not -path "./out*" -iname "*.7z" -exec sh -c '7za x $1 -o/dev/shm/7z; 7za a -t7z -m0=lzma -mx=9 -mfb=768 -md=384k -ms=off out/$1 /dev/shm/7z/*; rm /dev/shm/7z -r' \{\} \{\} \;
     
  3. CheatFreak47

    CheatFreak47 Complex Donut

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    That's what i had to do. Its roughly 66gb fully extracted. You might be able to batch compress everything to another archive format to save space, but if you aren't tight on space, I'd say just keep everything extracted for quick loading and access.
     
  4. Devante
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    Devante Crescent fresh at best.

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    Does anyone know the maximum safe size for dictionary? I find even a few of my SNES ROMs have the same problem.
     
  5. PsyBlade

    PsyBlade Snake Charmer

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  6. Devante
    OP

    Devante Crescent fresh at best.

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    Thanks for pointing that out. I didn't realize you changed the flag!
    I'll try it out and report back!
     
  7. PsyBlade

    PsyBlade Snake Charmer

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    didn't change it - just quoted it verbatim from the 7za manual
     
  8. Devante
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    Devante Crescent fresh at best.

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    So I tried various dictionary sizes from 32m down to 8m. About 16m is when it starts giving the error. Anything below that actually doubles the file size! (although still a lot smaller than ALL the games together).

    I ended up just using UnGoodMerge to get the single games from each collection and using those on my Wii.