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    SubjectRe: [PATCH] Delete cryptoloop
    On Tue, 27 Jul 2004 01:40:47 -0700
    Junio C Hamano <junkio@cox.net> wrote:

    >
    > Jari's exploit uses the property that his watermarks are
    > encrypted to identical ciphertext blocks, but does it mean that
    > the technique can be used to prove that identical ciphertext are
    > from the watermarks and not coming from mere coincidence?
    >

    You can't prove anything by a single found watermark, but you can encode
    additional information by placing the watermarks at chosen offsets in your
    file.

    For example, take prime numbers starting at 2 as offsets, and place the
    encodings in a chosen order at those offsets.

    The chances for a random occurence of this pattern are marginal, and -
    unless the watermarked file becomes strongly fragmented - this pattern is
    easy to retrieve.

    While this might not be evidence in the legal sense (it could well be, but
    IANAL), it is at the very least a strong indication.

    Regards
    -
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