respimage/plugins/typesupport/ri.type.js

The fast, lightweight and reliable polyfill for responsive images (i.e. picture element and the srcset, sizes and media attributes). With a smart resource selection algorithm, that saves bandwidth.

(function( factory ) {
	"use strict";
	var interValId;
	var intervalIndex = 0;
	var run = function(){
		if ( window.respimage ) {
			factory( window.respimage );
		}
		if(window.respimage || intervalIndex > 9999){
			clearInterval(interValId);
		}
		intervalIndex++;
	};
	interValId = setInterval(run, 8);

	run();

}( function( respimage ) {
	"use strict";

	var ri = respimage._;
	var runningTests = 0;
	var setTypeValue = function(types, value){
		var i;
		for(i = 0; i < types.length; i++){
			ri.types[types[i]] = value;
		}
	};

	if(ri.supPicture && !ri.cfg.uT){
		respimage.testTypeSupport = function(){};
		return;
	}

	ri.types["image/bmp"] = true;
	ri.types["image/x-bmp"] = true;

	respimage.testTypeSupport = function(types, url, width, useCanvas){
		if(typeof types == "string"){
			types = types.split(/\s*\,*\s+/g);
		}
		var canvas;
		var supports = "pending";
		var img = document.createElement('img');
		var onComplete = function(){
			runningTests--;
			setTypeValue(types, supports);
			if(runningTests < 1){
				respimage({reevaluate: true});
			}
		};

		if(useCanvas){
			canvas = document.createElement('canvas');
			if(!canvas.getContext){
				setTypeValue(types, false);
				return;
			}
		}

		img.onload = function(){
			var ctx;
			supports = true;
			if(width){
				supports = img.width == width;
			}

			if(useCanvas){
				ctx = canvas.getContext('2d');
				ctx.drawImage(img, 0, 0);
				supports = ctx.getImageData(0, 0, 1, 1).data[3] === 0;
			}
			onComplete();
		};

		img.onerror = function(){
			supports = false;
			onComplete();
		};
		runningTests++;
		setTypeValue(types, "pending");
		img.src = url;
	};


	respimage.testTypeSupport("image/webp", "data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAAADABAJ0BKgEAAQADADQlpAADcAD++/1QAA==", 1);
	respimage.testTypeSupport("image/jp2 image/jpx image/jpm", "data:image/jp2;base64,/0//UQAyAAAAAAABAAAAAgAAAAAAAAAAAAAABAAAAAQAAAAAAAAAAAAEBwEBBwEBBwEBBwEB/1IADAAAAAEAAAQEAAH/XAAEQED/ZAAlAAFDcmVhdGVkIGJ5IE9wZW5KUEVHIHZlcnNpb24gMi4wLjD/kAAKAAAAAABYAAH/UwAJAQAABAQAAf9dAAUBQED/UwAJAgAABAQAAf9dAAUCQED/UwAJAwAABAQAAf9dAAUDQED/k8+kEAGvz6QQAa/PpBABr994EAk//9k=", 1);
	respimage.testTypeSupport("image/vnd.ms-photo", "data:image/vnd.ms-photo;base64,SUm8AQgAAAAFAAG8AQAQAAAASgAAAIC8BAABAAAAAQAAAIG8BAABAAAAAQAAAMC8BAABAAAAWgAAAMG8BAABAAAAHwAAAAAAAAAkw91vA07+S7GFPXd2jckNV01QSE9UTwAZAYBxAAAAABP/gAAEb/8AAQAAAQAAAA==", 1);
	respimage.testTypeSupport("video/vnd.mozilla.apng video/x-apng video/png video/apng video/x-mng video/x-png", "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANSURBVAiZY2BgYPgPAAEEAQB9ssjfAAAAGmZjVEwAAAAAAAAAAQAAAAEAAAAAAAAAAAD6A+gBAbNU+2sAAAARZmRBVAAAAAEImWNgYGBgAAAABQAB6MzFdgAAAABJRU5ErkJggg==", false, true);

}));