@eqy @ptrblck Is there something I am fundamentally misunderstanding about masks being inputted to multi-class segmentation models? How should the mask look after we update it by doing the mapping? Should it have as many channels as there are classes, in which for each channel you see a true or false in each pixel if that pixel should have the class color or not? Should I be able to save my mask as an image after the mapping and still be able to view it normally? Sorry for all the questions I am just confused.