If you compute the hash you can save it and run it again later when more files are added. If you go the diff or eq route, you have to read the entire file for each compare.

He doesn't seem to take advantage of hash-caching here, but it would also speed up subsequent compares of the file against the next potential duplicate.

In reply to Re^2: Comparing duplicate pictures in different directories by elwarren
in thread Comparing duplicate pictures in different directories by cajun

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