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Subject: How to find similar images
Date: Wed, 8 Aug 2007 22:36:10 +0000 (UTC)
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I have a large set of color images. I wish to find a
characteristic number for each of them, so closer numbers
would represent "similar" images (in very loose terms). I'd
like the characteristic to be tolerant to cropping &
resizing and if possible also to rotation, flipping &
saturation. If possible, I'd also like it to be computed
quickly (my set is very large).

The ultimate aim is to winnow down the large set to a much
smaller subset of potential matching images, that would then
be inspected manually.

Some simple functions that I thought of were the grayscale
rms/mode/std/kurtosis/skewness. Could anyone please comment
on which of these functions (or any other) would be best for
my needs?

(I'm not an imaging expert nor have the Image Processing
Toolbox...)

Thanks in advance,
Yair