Assets loadBitmapData get id /asseth path after onComplete?

I’m using HTML5 and if use embed , the final js file is about 15 MB, so my only options is to load asynchronously all assets.
So my problem i with onComplete(…) . It’s return only bitmapdata, but I want to get also id, so I will know which image was loaded and can use taht information to dispatch event with image id and bitmapdata.
Is it possible at all ?

I think this might work:

<asset path="Assets" embed="false" />
var id = "Assets/image.png";
Assets.loadBitmapData (id).onComplete (function (bitmapData) {
    trace (id);
    trace (bitmapData);