What I'm looking for is something to compare two files, specifically images. Most hashing algorithms are designed to generate vastly different hashes with only slight differences in the source files, but I need the exact opposite, something that will tell me how similar two files are.

Does anything like this already exist? Could someone point me to a good resource for finding out about this sort of thing?

In reply to I need a comparison/hashing algorithm (not the usual). by Cap'n Steve

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