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Re: Analyse particles: counting eggs query

Posted by Joel Sheffield on Sep 16, 2005; 6:51pm
URL: http://imagej.273.s1.nabble.com/Analyse-particles-counting-eggs-query-tp3704847p3704850.html

You might also try the watershed algorithm to see if you can split
some of the joined profiles.

> Hello all,
>
> I've recently been using the image J "analyse", "analyse particles"
> function to count mosquito eggs (digital photo taken of black eggs on
> white filter paper).
>
> One difficulty is that the eggs tend to stick to each other, and often
> appear lying side by side.  In this instance, Imaje J counts all the
> eggs that are not separate as one.
>
> Manually separating the eggs out without damaging them is quite
> difficult and very time consuming.  Luckily the eggs do not vary much
> in size , so to overcome this problem, I have worked out the size
> range (in pixels) of an average single egg (9 - 22 pixels).  I carry
> out 3 counts:
>
> 1. < 9 pixels
> 2. 9-22 pixles
> 3. > 22 pixels
>
> Particles counted in the first range are too small to be eggs and are
> probably dust / artifacts (large artefacts are removed from the photo
> prior to processing).  Particles in the second range are all the eggs
> that have been counted singly, while particles in the 3rd range are
> eggs that are stuck together and have been counted incorrectly.  To
> get a total (more accurate) count,  I use this formula:
>
> Range 2 Count + (Range 3 total area / range 2 mean particle area).
>
> (Areas are in pixels - means are taken from each photo to account for
> differences in zoom etc)
>
> So here is my query; currently I am using an excel sheet to compute
> the formula - I add the necessary results from Image J manually to the
> excel sheet.  Would it be possible to feed the Image J results I need
> directly into the excel sheet?  If so how would I do this?
>
> BTW we are trying to set up this system to use in experiments where
> large numbers of egg papers will be processed on a daily basis (by
> various people).  Using image J as opposed to counting manually is
> already a vast improvement (both time-wise and in terms of human
> error), so what I'm after is a bit of fine tuning to further expedite
> the process.
>
> Any advice / help on this would be greatly appreciated...
>
> Thanks,
>
> Amy.
>
>
>
> -------------------------------------------
> Amy Mikhail
> Research student
> University of Aberdeen
> Zoology Building
> Tillydrone Avenue
> Aberdeen AB24 2TZ
> Scotland
> Email: [hidden email]
> Phone: 00-44-1224-272880 (lab)


Joel B. Sheffield, Ph.D.
Biology Department, Temple University
1900 North 12th Street
Philadelphia, PA 19122
[hidden email]  
(215) 204 8839, fax (215) 204 0486
http://astro.temple.edu/~jbs