comparing images programmatically - lib or class [closed]

Question

My objective is to supply 2 image files, and get a true/false response as to whether these 2 files could be the same (within an acceptable degree of certainty).

I realize this question falls under artificial intelligence and is much more complex than it appears, so I highly doubt I could (or would even want to) do it myself. What I'm looking for is probably a library or a class. I'm working with PHP.

thanks in advance..

All helpful answers/comments get up voted..

Update:

I wonder if I'm over-complicating it, and maybe a more general library like imageMagick (imagick) could get it done? Anyone who's more experienced with imageMagick?

Answer 1

I didn't try it, but maybe Libpuzzle might do the trick (quoting) :

The Puzzle library is designed to quickly find visually similar images (GIF, PNG, JPG), even if they have been resized, recompressed, recolored or slightly modified.

This is a C library, but is also comes with a command-line tool and PHP bindings.

And there is an example in PHP there.

(It seems to be a PHP extension -- which means you'll need to be admin of your server to be able to install it)