http://imagej.273.s1.nabble.com/best-way-to-select-a-range-of-colors-tp5011526p5011527.html
at least in the posted JPG-image there is very little color information.
> Hi people, in the past I've used ImageJ/Fiji mostly for grayscale
> images, so I have little experience in the color world. Now I have
> some samples treated with a stain and I thought I would separate
> stained vs unstained particles. But it was not as straightforward as
> I expected (at least with the approach I'm using).
>
> Here's the original image.
>
https://www.dropbox.com/s/yc7v90wv9s6rwje/initial_image.tif?dl=0>
> This is after I automatically re balance colors (for this step I used
> "auto adjust colors" in IrfanView, for some reason I can't get ImageJ
> to reach the same nice result with any of the "auto" options of the
> Color Balance
> tool):
https://www.dropbox.com/s/lcmo93oce8rupze/step2_colors_autobalanced.tif?dl=0>
> In this image I pointed most of the interest particles so you can
> see the range of colors I'm looking for.
>
https://www.dropbox.com/s/c78z37jbzsae223/some_interest_particles.jpg?dl=0>
> So the (unsuccessful) approach I tried is:1- manually select a few
> interest particles2- generate the color (RGB) histogram of those3-
> note the mean and standard deviation of each RGB4- with the Color
> Threshold tool, select the mean +/- 1-2 SD of each R, G and B
>
> but this does not produce the desired threshold. I'm sure this
> problem is as old as ImageJ so there must be tens of better ways,
> could you advice on this?Thanks a lot, Rodrigo
> ________________________ Rodrigo J. Gonçalves
>
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