Analysis of particles size

I am been trying to measure the size of particles using the watershed segmentation lines. However, the result is not as expected because the software doesn’t detect all the pretended particles.
Someone can help me?
Thanks.C_5000X COMP-watershed-lines.tif (1.2 MB) result


Would you be able to share with us an original image file? That would be very helpful. Also - what were the exact image processing steps that you have carried out thus far?

Original image: C_5000X COMP-watershed-lines.tif (1.2 MB)

This image was obtained using the MorphoLibJ plugin and now I want to measure the size of each particle.

I am using the menu Analyze - Analyze particles.

Ok. But this image is not the original correct? Would it be possible for you to share the original?

Too - what functionality did you use in MorpholibJ? Perhaps you can instead generate a labeled output and then use other tools in that collection to do the area measurements - just stick with MorpholibJ tools?

yes correct.
This is the orignal image: C_5000X COMP.tif (1.2 MB)
I want to segment the image and find the size of the particles.
I use the following sequence:
Plugins - MorphoLibj - Segmentation - Morphological Segmentation.

Hi @pedro_carneiro and welcome to the forum.
thank you for sharing the original image.

I quickly had a look using MorpholibJ and the results looked promising:

I think that by adjusting the settings a bit you can get even better results.

As an input image for MorpholibJ I used a crop of the original to, i.e., without the scale bar and annotation in the bottom.
To do so, you can use the rectangle tool to choose the “crop region” and then press “ctrl+shift+d” (or go to Image > Duplicate)

Hope this helps!

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I also obtained a similar result. The problem is when I export the image with the watershed lines I am not able to obtain the size of each particle using the sequence analyze - analyze particles.

I guess the problem is that the watershed lines are not sufficient for the Particle Analyzer.
The Particle Analyzer requires also a diagonal separation.
You need to expand them using Process > Binary > Erode.


@schmiedc If you use your suggestion in the image with the watershed line all of them disappears.

Ok then your foreground / background settings are different from mine.
Use the dilate command instead.

To make sure you have this consistently set use:
Edit > Options > Colors
Process > Binary > Options…

In this case what definitions should be selected in each menu.

Dilated lines - dilate_lines.tif (1.2 MB)
Results - result.tif (1.2 MB)

I usually stick with
Foreground: white
Background: black

Binary options: Black Background ticked

Then you should be fine I guess.


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It works. Thanks a lot.