dist/picturefill.js
function(func, wait) {
				var timeout, timestamp;
				var later = function() {
					var last = (new Date()) - timestamp;

					if (last < wait) {
						timeout = setTimeout(later, wait - last);
					} else {
						timeout = null;
						func();
					}
				};

				return function() {
					timestamp = new Date();

					if (!timeout) {
						timeout = setTimeout(later, wait);
					}
				};
			}
function(func, wait) {
				var timeout, timestamp;
				var later = function() {
					var last = (new Date()) - timestamp;

					if (last < wait) {
						timeout = setTimeout(later, wait - last);
					} else {
						timeout = null;
						func();
					}
				};

				return function() {
					timestamp = new Date();

					if (!timeout) {
						timeout = setTimeout(later, wait);
					}
				};
			}
Also attach picturefill on resize and readystatechange http://modernjavascript.blogspot.com/2013/08/building-better-debounce.html