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/*!
* Retina.js v1.1.0
*
* Copyright 2013 Imulus, LLC
* Released under the MIT license
*
* Retina.js is an open source script that makes it easy to serve
* high-resolution images to devices with retina displays.
*/
(function(){var root=typeof exports=="undefined"?window:exports;var config={check_mime_type:true};root.Retina=Retina;function Retina(){}Retina.configure=function(options){if(options==null)options={};for(var prop in options)config[prop]=options[prop]};Retina.init=function(context){if(context==null)context=root;var existing_onload=context.onload||new Function;context.onload=function(){var images=document.getElementsByTagName("img"),retinaImages=[],i,image;for(i=0;i<images.length;i++){image=images[i];retinaImages.push(new RetinaImage(image))}existing_onload()}};Retina.isRetina=function(){var mediaQuery="(-webkit-min-device-pixel-ratio: 1.5), (min--moz-device-pixel-ratio: 1.5), (-o-min-device-pixel-ratio: 3/2), (min-resolution: 1.5dppx)";if(root.devicePixelRatio>1)return true;if(root.matchMedia&&root.matchMedia(mediaQuery).matches)return true;return false};root.RetinaImagePath=RetinaImagePath;function RetinaImagePath(path,at_2x_path){this.path=path;if(typeof at_2x_path!=="undefined"&&at_2x_path!==null){this.at_2x_path=at_2x_path;this.perform_check=false}else{this.at_2x_path=path.replace(/\.\w+$/,function(match){return"@2x"+match});this.perform_check=true}}RetinaImagePath.confirmed_paths=[];RetinaImagePath.prototype.is_external=function(){return!!(this.path.match(/^https?\:/i)&&!this.path.match("//"+document.domain))};RetinaImagePath.prototype.check_2x_variant=function(callback){var http,that=this;if(this.is_external()){return callback(false)}else if(!this.perform_check&&typeof this.at_2x_path!=="undefined"&&this.at_2x_path!==null){return callback(true)}else if(this.at_2x_path in RetinaImagePath.confirmed_paths){return callback(true)}else{http=new XMLHttpRequest;http.open("HEAD",this.at_2x_path);http.onreadystatechange=function(){if(http.readyState!=4){return callback(false)}if(http.status>=200&&http.status<=399){if(config.check_mime_type){var type=http.getResponseHeader("Content-Type");if(type==null||!type.match(/^image/i)){return callback(false)}}RetinaImagePath.confirmed_paths.push(that.at_2x_path);return callback(true)}else{return callback(false)}};http.send()}};function RetinaImage(el){this.el=el;this.path=new RetinaImagePath(this.el.getAttribute("src"),this.el.getAttribute("data-at2x"));var that=this;this.path.check_2x_variant(function(hasVariant){if(hasVariant)that.swap()})}root.RetinaImage=RetinaImage;RetinaImage.prototype.swap=function(path){if(typeof path=="undefined")path=this.path.at_2x_path;var that=this;function load(){if(!that.el.complete){setTimeout(load,5)}else{that.el.setAttribute("width",that.el.offsetWidth);that.el.setAttribute("height",that.el.offsetHeight);that.el.setAttribute("src",path)}}load()};if(Retina.isRetina()){Retina.init(root)}})();