Use the filesize to seed a random number generator, and then read 100 random 4- or 8-byte chunks from the file, stick'em together and checksum them.

The odds of duplicates are billions to 1.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re: high speed checksum for video finger printing? by BrowserUk
in thread high speed checksum for video finger printing? by faber

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