Re: Area measurements for 50 particles on one image (image attached)

Posted by Nathaniel Ryckman on Jun 20, 2011; 3:20pm
URL: http://imagej.273.s1.nabble.com/Area-measurements-for-50-particles-on-one-image-image-attached-tp3684189p3684190.html

Image segmentation seems to be a big problem. I am almost finished with a segmentation plugin that should help universally solve the problem.

Until then, however, like others have mentioned, you could change the lighting.

Here is my best attempt at trying to segment this image using the "standard tools" available in imageJ.





I cropped the image and inverted the colors to make it easy to work with.

1) Process->Subtract Background->Rolling Ball
2) Image Calculator (original image - duplicate image with 250 mean blur = image used in next step)
3) Guassian blur of 2
4) Autothreshold/binarize
5) Watershed
6) Particle Analyzer

janaka kumara wrote

Dear all,
 
In this image, there are 50 particles. I want to measure areas for each particles but when I do using ImageJ toolbar, I don't get area measurements for all particles (50). I do analyses as follows,
 
- Analyze, then Set Scale (to set a scale)
- Rectangle shape selection (to remove ruler on the image)
- Edit, then clear outside (now only particles remained on the image)
- Process, then Find Edges
- Process, then Binary, then Make Binary
- Process, then Binary, then Dilate (as images are not very clear)
- Analyze, then Analyze particles, there
        size (mm2): 5-infinity
        circularity: 0-1.00
        show: outlines
 
Then, on the result sheet, I cannot see data for exactly 50 particles.
 
Could you please advice me on this matter?
 
Note: due to limitation for size, image attached was resized. If you want the original image, I can give you it if you will send me your email address.
 
Thank you.
 
Yours sincerely,
Kumara

PhD candidate
Geotechnical Engineering Laboratory
Department of Civil Engineering
Yokohama National University, Japan