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From: ImageAnalyst &lt;imageanalyst@mailinator.com&gt;
Newsgroups: comp.soft-sys.matlab
Subject: Re: Horn Detection in Leukaemia Images
Date: Tue, 17 Feb 2009 11:44:53 -0800 (PST)
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Lee Borland:
regionprops will give you the perimeter, area, and solidity.  In a
loop, go through all the blobs examining the ratio (4*Perimeter^2)/
(pi*Area) and the solidity measurement.  There will be some number for
smooth contour blobs, that will distinguish the two.  For example the
ratio &lt; 5 for smooth blobs and is &gt; 5 for &quot;horny&quot; blobs.  You may also
see some value were you can distinguish the two kinds of blobs based
on the solidity value.

If counting the number of blobs is important, then that's tougher
since not all of the horns appear on the perimeter - some appear in
the middle of the blob.  If it were just the perimeter then you could
erode a few pixels (to get rid of horns) then dilate out a bit more
than you eroded and find the boundary of that (using bwboundaries).
That would give a line (the outline) a little bigger than the main
bulk of the blob and then you could run around this to see where a
horn intersected it.  However you may still have horns on the back
side of the blob that you can't see so I'm wondering if you can't
really get what you need with out the horn count.  Maybe it's not
necessary.  If it is, you're out of luck since you can't see the back
side and getting the ones in the middle will be tough.  You may have
to fall back to manual inspection where a user enters the number of
horns they see.  And of course even this won't tell you how many horns
are on the back side and thus are unseen in the image, so you'll never
really have the true number anyway.
Regards,
ImageAnalyst
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