Find similar images using python

[Scott David Daniels]

Thomas W wrote:
> How can I use python to find images that looks quite similar? Thought
> I'd scale the images down to 32x32 and convert it to use a standard
> palette of 256 colors then compare the result pixel for pixel etc, but
> it seems as if this would take a very long time to do when processing
> lots of images.
> 
> Any hint/clue on this subject would be appreciated.

This question is immensely non-trivial unless you can form a precise
definition of "images that look quite similar."  It is one of those
deceptive problems that seem straightforward, but become less and less
well-defined the more you study it.  If you can solve this you can
get a PhD, get rich, get famous, or a combination of all three.

The US Supreme Court gave up on identifying pornography, because
the best definition anyone ever came up with was "I know it when I
see it," a judgment quite reasonable in a legal system based on
trusted authorities, but not a good one in a society "ruled by laws
and not men."

--Scott David Daniels
scott.daniels at acm.org