How do I customize QueryLoader so it doesn't do the animation if it already loaded once or cached?

Question

I'm using QueryLoader (jquery) to preload images for my site and that works great! Is there a way to check if the images were already loaded before or cached so I can skip the animation? It seems like overkill.

Something like

setTimeout(function () { if image loaded else trigger animation }, 1000);

link to page
http://www.gayadesign.com/diy/queryloader-preload-your-website-in-style/

Thanks.