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From: ImageAnalyst <imageanalyst@mailinator.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Image comparison
Date: Tue, 27 Jan 2009 08:34:17 -0800 (PST)
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Niall:
There's tons and tons of research on this subject.  It's usually
called "image registration."  MATLAB even has a help entry for this,
if you have the image processing toolbox.  This usually refers to the
images being the same size and largely overlapped (like your
situation) and rotated, warped, etc.  There's a related field called
"pattern matching" where the "pattern" image is usually just a small
sub-part of the larger image (and of course it could be translated,
rotated, warped, or even partially occluded in the main image).  This
is big in the defense field for obvious reasons.  So, given that
there's a bazillion methods for doing it, and more coming out every
month, I suggest that you first do a literature search to find
something similar to your situation and that might meet your needs.
Or, for starters, you could check out the stuff MATLAB supplies in the
image processing toolkit.
Regards,
ImageAnalyst