Background image with a draggable second image (layers maybe)

I need to be able to take a background image and float a second draggable image (should be scalable, but with fixed proportions) Also the cod开发者_运维技巧e should be able to 'flatten' the image for photo sharing. Oh, also the floating image should have a dropped shadow to give the illusion of depth. Thanks! Is this possible with jQuery, ajax, Yui or Dojo(other?)? Or am I barking up the wrong proverbial code trunk.

It's definitely possible to layer a draggable, scalable, fixed-proportioned image with a drop shadow on top of a background image using jQuery or some other JavaScript library. However, flattening the two into one image for photo sharing will require some server-side code that does the image manipulation.