Legacy ImageMagick Discussions Archive

I noticed, that "difference" of two images looks very alike with Gimp's one
But "subtract" operation result is not even near Gimp's version. Is it possible somehow to do it the same way as Gimp does?

Thank you for your answer. It's not what I'm looking for, unfortunately. I should explain why I need that operation. It's a kind of a 3-axis distance function for a RGB difference of two images, distance = sqrt(r**2 + g**2 +b**2) it allows to turn RGB difference to a better grayscale one, than allow...

Thank you. It can help a bit, indeed.
But fx is very slow anyway. I was hoping to find a non-fx way.

Please!!!
Help to find a faster way to do the following
-fx 'sqrt(r**2 + g**2 + b**2)'