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This is crude, but you can try zipping them separately for comparison and zipping their concatenation. If they are similar, you'll get a higher compression ratio than if not.

Another possibility to to apply a fast fourier transform to each and multiply them pointwise. That will give the fourier transform of their correlation function. That has the potential to give very precise results, but maybe hard to interpret. Similar files will produce a strongly peaked correlation function.

If you want to try the second route, PDL is the way.

After Compline,
Zaxo

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

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