I have about 40 bitmap (png) files which have 3 parts (clearly separated, you can draw 3 rectangles not touching each other containing those parts, and on all files those rectangles are in exactly the same position). Those bitmaps are procedurally generated by a program that I have no way to modify. I am happy with contents of each of the parts, but I would like to have them rearranged into other positions (the same for each file). Doing it manually is possible (40 is not 4000) but will take a lot of time and likely I will not move to exactly same positions. Is there any software (preferably free and for Windows) which allows me to manipulate all my bitmaps in exactly the same way?