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Histogram image

Member for

1 year 1 month jordidomingo

Hello everyone. First of all I’d like to thank you all, because, although it’s my first time posting on this forum, I’ve read a lot and helped me creating my workflows.

I’m working with images, and I have splitted (with splitter node) them into  their RGB channels. Now I have the histograms, and somehow, i’d like to transform all that information into data. Can I do that?

Comments
Wed, 02/28/2018 - 09:43

Member for

6 years

gab1one

Hi Jordidomingo,

I am glad that the forum has been helping you so far, I am positive we can help you with this question too.

With: "Now I have the histograms" do you mean the histogram view in the Image Viewer? If you want such a histogram in data, you can use the Feature Calculator node, when you select the Histogram Features feature set, you can let it create a histogram with any number of bins you desire.

best,

Gabriel

Wed, 02/28/2018 - 09:49

Member for

6 years

gab1one

With the histogram view I mean the one you can see in the attached screenshot.

Files
Wed, 02/28/2018 - 02:48

Member for

1 year 1 month

jordidomingo

Yes, you’re right, I have one histogram like that. Two questions:

- Do I have to configure the festure calculator node like this? (Image attached)

- Why do we have like to histograms inside the same image? One darker than the other?

Thu, 03/01/2018 - 01:37

Member for

6 years

gab1one

- Yes that setting looks correct to me, if you want a 255 bins histogram.

- The black histogram is the histogram in absolute numbers, the grey one is log-scaled.

Sat, 03/03/2018 - 11:53

Member for

1 year 1 month

jordidomingo

Thank you for your help.

My question now is, can I get a vector of the image but, instead of the histogram, of the value of each pixel?

Should I use image to data raw node?