blockquote>About the best you can do is compute two more different digests of the document which should make it much, much harder to generate two disperate, but meaningful documents that produce the same digests through the different hash functions.

As far as I know, most digests (MD4, MD5, SHA1...) are relying upon the same mathematical rules and concepts (such as Galois groups). As virtually all of these digest systems have be "broken", it may be conceivable to forge two different files sharing more than one digest type !

In reply to Re^5: compare images by wazoox
in thread compare images by Anonymous Monk

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