Notes

Notes:

Determines the size of an image:
<script>
function onImageLoad(aEvent) {
	  alert("width:" + aEvent.target.width + "\nheight:" + aEvent.target.height);
	}
	
var img = document.createElementNS("http://www.w3.org/1999/xhtml","html:img");
img.addEventListener("load", onImageLoad, false);
img.src = "http://upload.wikimedia.org/wikipedia/commons/0/06/Gigantactis.jpg";
</script>

OR largest image on the page:

<script>
var sHTML = getHTMLSomehow(sURL);
var nMaxDim = 0;
var $pageDOM = $(sHTML);
var $objMaxDimImage;

$pageDOM.("img").each(function(){
    var $this = $(this);
    var nDim = parseFloat($this.width()) * parseFloat($(this).height());
    if (nDim > nMaxDim){
        $objMaxDimImage = $this;
        nMaxDim = nDim
    }
});

alert("Max dim is:" nMaxDim);
alert("Image Source:" $objMaxDimImage.attr("src"));
</script>