Posted by
Robert Dougherty on
Nov 03, 2009; 1:07am
URL: http://imagej.273.s1.nabble.com/Counting-Barnacles-on-a-panel-tp3690575p3690576.html
Emiliano,
I think this is a job for the Hough transform. A way to start is to
subtract the background, convert to 32-bit, find edges, and do an
"adjust threshold" with limits of something like 175-743. Now the
little varmints are represented by reasonably well defined circles and
arcs. This should be perfect for the Hough transform. The only Hough
transform plugin that I've found so far is Hough Circles, and I can't
seem to get it to work well in this case. Also, the Hough Circles
link is missing from the Plugins page. Perhaps someone else on the
list knows how to drive it or knows of a more suitable plugin. This
is a rather basic capability that ImageJ should have if it does not.
Bob
On Oct 29, 2009, at 7:24 AM, Emiliano Pinori wrote:
> Hi,
> I'm working on antifouling marine paints and had lots of panels to
> analyze.
> I found ImageJ a very helpfull tool. Anyway when it cames to the
> more adult
> and close togheter barnacles individuals on my panels i had
> experienced some
> difficoults in using my very simple macro to count for Barnacle at
> the ROI
> area.
> I use a subtcract background, followed by set scale, rectangular
> selection
> find maxima within tollerance, and finally analyze Particles.
>
> Now the problem is that I will lose a lot of adult barnacles in my
> results
> becouse they will never become not even 0.5 circular after find
> maxima due
> to the close presence of ather smaller barnacle. Or becouse the edge
> do not
> are at the same brightness all over the preimeter. How can i improve
> the
> accurancy without having too much false positives?
>
> I don´think I asked my question in a understandable way, so i put a
> photo of
> wath i have to analyze and hope someone understand me anyway.
>
> I need counts and area to have a % difference between Prov and
> Control side
> (just a 9 square cm ROI of each side)
>
>
http://s943.photobucket.com/albums/ad273/zapatainsvezia/Barnacles%20Exemp/>
> thank you Emiliano Pinori
> Ph.D. student
> Gothemburg University (Sweden)
> --
> View this message in context:
http://n2.nabble.com/Counting-Barnacles-on-a-panel-tp3912808p3912808.html> Sent from the ImageJ mailing list archive at Nabble.com.
Robert Dougherty, Ph.D.
President, OptiNav, Inc.
4176 148th Ave. NE
Redmond, WA 98052
(425)891-4883
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