image overlays – how difficult

i want to do something like this on my website but don't know how difficult it might be or how much it might cost.. something similar to the fabric viewer at http://www.polstitchesdesigns.co.uk/fabricviewer.htm. you select the first image (here it's the pattern) and then put a background image (the fabric here) behind that image to show the customer what their product would look like.

See original post by tyankee