See http://www.cnet.com/forums/discussions/how-to-make-a-gif-from-two-image-files/
Locking this one.
I have two very simple image files (created in powerpoint, so they are very basic) and wish to make a gif file from the two images, showing one image turning into another. Is there any software I can use to do this. I've seen software that you can use online to create a gif from two or more images, but all they do is basically show each image in a frame, so that the two images don't gradually change into each other.