Posted by
Gabriel Landini on
Mar 28, 2016; 9:41am
URL: http://imagej.273.s1.nabble.com/Getting-started-with-grain-size-analysis-tp5016013p5016015.html
On Sunday 27 Mar 2016 20:14:53 you wrote:
> I am new to the list and have close to no experience with ImageJ (or
> image analysis) but have a solid background in physics and programming.
> I am facing the task of determining grain size distribution in photos
> from industrial camera. A typical image is like this:
>
http://i.imgur.com/lwuOBeh.jpg (the diagonal separates two types of
> material which has different reflecitivity). The eventual goal is an
> unattended analysis under controlled conditions (same lighting,
> resolution etc). I have some issues getting a reasonable result with
> ImageJ and I would appreciate some help on how to move forward. Could
> someone suggest a way I could try?
The image you posted has too many issues and I doubt that you would be able
the analysis you want accurately without redesigning your setup.
The first problem is the overlapping. You would do much better if your
particles were on a single layer on a contrasted background. maybe you can get
some surface with wells where each grain sits in one of those.That would also
help with identifying the individual objects.
You should aim to reduce the uneven illumination. I would suggest that you try
to resolve this issue before image capture, as doing it programatically tends
to create new artefacts. Have you tried a light diffuser? or several light
sources?
Also note that JPEG images are not good for imaging. They are lossy
compressed, which add image artefacts which further interfere with the
subsequent processing. Better save your data in TIFF or PNG formats. Saving a
JPEG to TIFF to PNG does not resolve anything as the artifacts are already
there.
Hope this helps
Gabriel
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