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    SubjectRe: reverse engineering pwcx
    > The LavaRnd guys examined the pixels on the actual
    > CCD chip. It's 160x120. The 'decompression' is
    > just interpolation.

    First of all, it's not a CCD chip. It's CMOS.

    Now, here's a Bayer pattern:


    Don't put much faith in the 160x120 number. Suppose
    that the chip is in a Bayer pattern, with 160x120
    of those. Well, how many pixels is that? Who knows.
    You'd sort of have 160x120, but with double the
    green data. Since green carries most of the luminance
    information, producing a larger image is reasonable.

    Suppose the pattern is larger. The "Bayer" name in
    the code may well be misleading. Each "pixel" that
    was counted could be a 4x4 grid with 6 red subpixels,
    8 green subpixels, and 2 blue subpixels. What's that?
    You count 160x120, because it looks that way, but
    it's 640x480 subpixels.

    To correctly convert this to pixels while keeping the
    maximum amount of image data, I think you need to
    use the sinc() function. Problem is, you're getting
    pre-mangled data from the camera. So it gets a bit
    more complicated.

    BTW, what are the legal problems? I didn't click to
    agree on some EULA. I didn't sign an NDA. I don't
    see how this could be considered a copy-control or
    encryption system. Am I missing something? Maybe
    this ought to be a 2-person project?

    The code does look easy enough to take apart, even
    using plain objdump. I think I'd be doing so now if
    I had one of the cameras. (What nerd could resist?)
    The decompiler is a much cooler option though.
    By using both x86_64 and powerpc, recovery of data
    types should improve.

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