This made me curious, so I found things like this: www.cse.unr.edu/~bebis/UdayFingerprint.pdf‎ and www.csis.pace.edu/~ctappert/dps/IJCB2011/papers/200.pdf‎ The

This made me curious, so I found things like this: www.cse.unr.edu/~bebis/UdayFingerprint.pdf‎ and www.csis.pace.edu/~ctappert/dps/IJCB2011/papers/200.pdf‎ The features themselves are somewhat of a hash of the image, and as quantizable elements, they could be further hashed.