http://croozeus.com/blogs/?p=215
import appuifw import graphics # Creates new image with size 50,50 and uses mode 1 # Mode 1 indicates the image is only black and white - this is required for using masks # You can replace '1' by 'L' if you want to use a 8-bits grayscale image mask_img = graphics.Image.new(size = (50, 50), mode = '1') # Loads the mask mask_img.load('E:\\mask.png') # Opens main image main_img = graphics.Image.open('E:\\original.png') # Defines canvas for using as the application body canvas = appuifw.Canvas() # Sets the body to canvas appuifw.app.body = canvas # Blits the image with it's mask canvas.blit(main_img, target=(0,0), source=(0,0), mask = mask_img)