Hash functions like MD5 can have collisions. This means two different files can have the same MD5 checksum

You're right, they can. Indeed, I swear I actually saw this once when generating md5s from 1,000,000 web pages; but I never suceeded in reproducing it. People who understand statistics tell me that the likehood is extremely low. Like so low (unless you delibertely set out to achieve it), that hell is likely to freeze over first--or something like that :)

If you ever actually encounter two real files with the same md5s, and they are not proprietory or private, could you let me have a copy of each. I have some analysis code I would like to run on them.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: compare images by BrowserUk
in thread compare images by Anonymous Monk

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