image size detector for use in determining the size of image that may or may not be loaded (in lieu of img.load)

image-size-detector.js

// this imageSizeDetector works in lieu of img.onload
(function(jQuery){
  jQuery.fn.imageSizeDetector = function(callback){
    var $image    = this;
    var width     = 0;
    var height    = 0;
    var pollCount = 0;
    var callback  = callback;
 
    var interval = setInterval(function(){
      width = $image.outerWidth();
      pollCount++;
 
      // wait until the image is at least 40px wide
      // ... or until we've polled for 10 seconds
      if (width < 40 && pollCount < 200) return;
 
      clearInterval(interval);
 
      height = $image.outerHeight();
      callback(width, height);
    }, 50);
 
    return this;
  };
})(jQuery);