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Colormap for images

Member for

11 months 1 week mo

Hi,

I need to display an image using a colormap (e.g. like the "parula" colormap in MATLAB). I guess have to transform the actual image to a label map and then use the "apply color settings to labels" node. Unfortunately I'm not sure how to transform the image to a label map where every pixel intensity is a label? Is there any node to do this automatically? Or is there any other solution for my problem? An example workflow for the solution of the problem would be very nice!

 

Thanks!

Comments
Wed, 01/17/2018 - 02:23

Member for

5 years 8 months

gab1one

Hi mo,

did you try the Image to Labeling node? It should well with single channel images.

best

Gabriel

Wed, 01/17/2018 - 03:07

Member for

11 months 1 week

mo

Hi Gabriel,

thanks for your quick response, yes, I've tried it with this node, but I am not sure how to proceed? As far as I understand, after execution of the node I do have a label map, where every pixel has a label. But this labelling is independent from the actual intensity value of the pixel, so this is not helpful or am I wrong? My output from this node is only coloured noise without actual image information. For a colormap I need to assign specific colors to specific intensity ranges, not to specific labels how can I do that? I think the color manager might be a solution but how do I apply it to the actual image data it only works for labellings? Sorry about my confusion maybe it's very simple and I'm just not getting the point ;)

best

Mo.

Wed, 01/17/2018 - 03:30

Member for

5 years 8 months

gab1one

Hi Mo,

You can use the Intensity Binner node to create intensity ranges and map them to constant values before applying the Image to Labeling node.

best,

Gabriel

Wed, 01/17/2018 - 03:58

Member for

11 months 1 week

mo

Hi Gabriel,

thanks, that works but I think it is a very complicated solution for the actual problem, especially since I have to define the intervals in the intensity binner and the colortable for the color manager manually. So this is more or less useless if you want to apply a more or less continous color model with many bins and distinct shades of colors. Do you have any better solution?

Best regards,

Mo.

Thu, 01/18/2018 - 03:55

Member for

11 months 1 week

mo

Hi Gabriel,

solved the problem, the Color Manager offers the Range option, which I had not recognized, and binning can be performed with the Image Normalizer / Image Converter :)

 

Best regards,

Mo.

Thu, 01/18/2018 - 04:22

Member for

5 years 8 months

gab1one

I am happy you found a solution that works for you, we will work on a easier solution for this in the future.