Hide until background image loaded?

Hide until background image loaded?

Hi there, I'm a complete newbie to jQuery and haven't found the solution I'm after in the documents on this site.

I have a set of divs on my portfolio page that all share the common class 'module', with an additional class that determines the background image.

I currently have this function that I thought would keep each instance of .module hidden until it had loaded:

$('.module').ready(function(){
 
$('.module').fadeIn('9000');
});

I'm not certain but I think the 'ready' only refers to the HTML content and ignores the fact that the background image (defined in css) isn't ready. 

Is there any simple way I can make each div stay hidden until the background is loaded, then perform show() or fadeIn()???

The page in question can be found at http://www.orrinward.co.uk/new

Thanks for any help!