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  • Does anybody know/have Greenleaf ArchiveLib algorithm?

    From David Olsen@21:1/5 to All on Fri Jul 19 00:20:24 2019
    The now defunct Greenleaf ArchiveLib algorithm is used for an embroidery format called HUS and another called VIP and was a thing in the 1990s. The company is defunct and the algorithm wasn't adopted by anything else. So while these are compressed files
    there's little chance of writing a modern platform independent version of them. I know the source was released with the software does anybody have a copy or know what the core algorithm was for the level 4 algorithm, ALGLDecompressor.

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  • From Eli the Bearded@21:1/5 to [email protected] on Sat Jul 20 02:18:16 2019
    In comp.compression, David Olsen <[email protected]> wrote:
    The now defunct Greenleaf ArchiveLib algorithm is used for an embroidery format called HUS
    and another called VIP and was a thing in the 1990s. The company is defunct and the
    algorithm wasn't adopted by anything else. So while these are compressed files there's
    little chance of writing a modern platform independent version of them. I know the source
    was released with the software does anybody have a copy or know what the core algorithm was
    for the level 4 algorithm, ALGLDecompressor.

    I see there's a DLL that claims to implement that here:

    https://www.opendll.com/index.php?file-download=al21mfc.dll&arch=32bit&version=#

    How good are you are disassembly?

    Elijah
    ------
    otherwise has no leads

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  • From David Olsen@21:1/5 to All on Sun Jul 21 12:11:14 2019
    How good are you are disassembly?

    Elijah
    ------
    otherwise has no leads

    Actually the NSA released their disassembler the other month and ghida is fantastic. And it does very much get you at some source there, enough to see some of what it's doing.

    I think I found some source code for it, but as another lead elsewhere noted the source-code itself is obfuscated. I had initially thought the other source code was decompiled but I now believe it's original obfuscated code.

    I also put in some inquiries to find the heirs of the company. They can't be making money off it now, so it seems a bit of a long shot, but locate them, contact them, ask that the source code be released under a permissive open source license is a
    plausible idea.

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  • From David Olsen@21:1/5 to David Olsen on Mon Jul 29 21:40:38 2019
    On Friday, July 19, 2019 at 12:20:25 AM UTC-7, David Olsen wrote:
    The now defunct Greenleaf ArchiveLib algorithm is used for an embroidery format called HUS and another called VIP and was a thing in the 1990s. The company is defunct and the algorithm wasn't adopted by anything else. So while these are compressed
    files there's little chance of writing a modern platform independent version of them. I know the source was released with the software does anybody have a copy or know what the core algorithm was for the level 4 algorithm, ALGLDecompressor.

    They sublicensed an early version of ARJ. It's the same code with a 4k window and 511 element dictionary.

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