var getImageSize = function(imgSrc){
var imageSize = '';
var obj = new XMLHttpRequest();
obj.open('HEAD', imgSrc, true);
obj.onreadystatechange = function(){
if ( obj.readyState == 4 ) {
if ( obj.status == 200 ) {
//alert('Size in bytes: ' + obj.getResponseHeader('Content-Length'));
imageSize = obj.getResponseHeader('Content-Length');
} else {
}
}
};
obj.send(null);
return imageSize;
};