Re: 2D histogram of two channels

Posted by Jan Eglinger on
URL: http://imagej.273.s1.nabble.com/2D-histogram-of-two-channels-tp5022216p5022219.html

Dear Rainer,

in Fiji, you can get the result image of the Coloc_2 plugin directly via
scripting languages, e.g. using the following Groovy script:

```
#@ Img input1
#@ Img input2

import sc.fiji.coloc.gadgets.DataContainer
import sc.fiji.coloc.algorithms.Histogram2D

container = new DataContainer(input1, input2, 0, 0, "First", "Second")

hist2d = new Histogram2D("My custom 2D histogram")
hist2d.execute(container)

result = hist2d.getPlotImage()
```

The result image is 32-bit, so you will have to adjust the display range
to see anything.

For the red and green channel of the Clown sample image, I get the
attached result image. Interestingly, there seem to be some strange
artifacts in the 2D histogram image that I can't see in the 1d histogram
plots of the same image. Dan White (the author of Coloc_2) might want to
comment on this, but I'm not sure if he still subscribed to this mailing
list, so it might be worth asking on the image.sc forum instead:
https://forum.image.sc/

Best regards
Jan


On 04.06.2019 12:38, Rainer M. Engel wrote:

> Hey..
>
> I did some search for 2D histograms of two channels (or of two one
> channel/grey images).
>
> It would look for example like this:
> https://www.pyimagesearch.com/wp-content/uploads/2014/01/grant-2d-histograms.png
> Source [1]
>
> I found another resource, which describes image properties one
> could read from these [2]. By this I got some new search phrases and
> found Coloc 2 as an ImageJ-Plugin [3].
>
> Can this plugin export the resulting 256x256px 2D Histograms? I have not
> made this so far. Here they are called 2D intensity histograms. The
> distributions' weight is also shown with an overlayed straight line
> (regression line). This seems to be a static feature.
>
> Is there a way to access/store this "2D intensity histogram"?
>
> Any help is much appreciated.
>
> Regards,
> Rainer
>
>
> [1]
> https://www.pyimagesearch.com/2014/01/22/clever-girl-a-guide-to-utilizing-color-histograms-for-computer-vision-and-image-search-engines/
>
> [2] https://svi.nl/TwoChannelHistogram
>
> [3] https://imagej.net/Coloc_2
>
>

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