(function($){
var
props=['Width', 'Height'],
prop;
while (prop=props.pop()){
(function (natural, prop){
$.fn[natural]=(natural in new Image()) ?
function (){
return this[0][natural];
} :
function (){
var
node=this[0],
img,
value;
if(node.tagName.toLowerCase()==='img'){
img=new Image();
img.src=node.src,
value=img[prop];
}
return value;
};}('natural' + prop, prop.toLowerCase()));
}}(jQuery));