Improving Slice overlay functionality to visualize registration differences using different color "channel" for fixed and moving

To support generating overlay like this one (useful to visualize registration differences):


Image copied from here

An idea would be to add a new blending mode. Currently we have the following:


Would that generally be useful ?

cc: @Samuel_Gerber

Maybe the blending should be adding and you would pick colors that add together to white / gray. Then you’d a get grayscale image where the images are registered well and otherwise some of one or the other color

Hi - can you elaborate on what blend function that would be?

I am assuming we would have to write a custom blend function.

For reference, here is the code used to generate the figure above.

Hmm, I see, yes that could be useful. It would be easy enough to add a blend mode yes. Also though very easy to have a scripted module or cli that just makes a red/green mix of the two volumes with hot update. Could also be added as an extension to the CompareVolumes module. I don’t have a strong preference.


We currently do not need this feature, @Samuel_Gerber and I discussed this in the context of a proposal and I wanted to have this documented so that we could refer to it at a later time.