What compression is this?

Discussion in 'NDS - ROM Hacking and Translations' started by Naxito, Feb 27, 2011.

  1. Naxito
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    Naxito Advanced Member

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  2. Kaleid

    Kaleid Advanced Member

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  3. Zorua

    Zorua Newbie

    Try opening it using WinRAR.
     
  4. FAST6191

    FAST6191 Techromancer

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    I managed to grab the other day it but could not get anything done with it- I poked it around and while it apparently could decompress I only got garbage (I would expect a ncgr to give me some form of image- it decompressed to random little lines everywhere in all the things I tried- not noise that it was before but lines). This being said it did not error out the decompression tool which is what usually happens with a bad file.
    Crystaltile2 seems to think it is compressed (I stuck it in rom and had a look then), that it does not compress much and once "decompressed" decompresses back again to a similar size as the original file would support such an assessment as well.
    In the hex I did not look hard but nothing that usually gives LZ away (flags and the like) jumped out at me. I did not see any RLE type arrangements and 1bpp did not do much so that pretty much leaves huffman (which I also tried to see) but if it is custom huffman (even if it is just the "probability table" stashed somewhere unusual) that makes life difficult.

    All this is very odd.
    I think this might be an ASM hack- if there are files like it loaded earlier in the game do a bit of replacement and see if you can not hook things there.


    If someone else wants to try their hand and that link does not work then
    http://www.4shared.com/file/-8Tpm5Cl/archivo2.html
     
  5. Dark315055Vash

    Dark315055Vash Member

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    it should be Huffman (0x20) with a 8 bit pattern. there is the 0x24 too which is a Huffman with a 4 bit pattern.
     
  6. Naxito
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    Naxito Advanced Member

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    Thanks all

    Ok but, what i do? I don't know how work Huffman. Any idea?