There are several questions about zooming and panning with jQuery, but they all (as far as I can tell) have to do with hooking up the zooming or panning to user behavior, such as mousing or using a slider.
I'm interested in something different: any advice on making the panning happen automatically? The sort of thing I have in mind can be seen in this video:
I've whipped up a proof-of-concept demo. As pointed out in the comments, browser-powered image resizing can run into quality issues. You'd have to play with it, and decide for yourself if it looks good enough for your purposes.