HuajiMidi/js/midi/audioDetect.js

/*
	----------------------------------------------------------
	MIDI.audioDetect : 0.3.2 : 2015-03-26
	----------------------------------------------------------
	https://github.com/mudcube/MIDI.js
	----------------------------------------------------------
	Probably, Maybe, No... Absolutely!
	Test to see what types of <audio> MIME types are playable by the browser.
	----------------------------------------------------------
*/

if (typeof MIDI === 'undefined') MIDI = {};

(function(root) { 'use strict';

	var supports = {}; // object of supported file types
	var pending = 0; // pending file types to process
	var canPlayThrough = function (src) { // check whether format plays through
		pending ++;
		var body = document.body;
		var audio = new Audio();
		var mime = src.split(';')[0];
		audio.id = 'audio';
		audio.setAttribute('preload', 'auto');
		audio.setAttribute('audiobuffer', true);
		audio.addEventListener('error', function() {
			body.removeChild(audio);
			supports[mime] = false;
			pending --;
		}, false);
		audio.addEventListener('canplaythrough', function() {
			body.removeChild(audio);
			supports[mime] = true;
			pending --;
		}, false);
		audio.src = 'data:' + src;
		body.appendChild(audio);
	};

	root.audioDetect = function(onsuccess) {
		/// detect jazz-midi plugin
		if (navigator.requestMIDIAccess) {
			var isNative = Function.prototype.toString.call(navigator.requestMIDIAccess).indexOf('[native code]');
			if (isNative) { // has native midiapi support
				supports['webmidi'] = true;
			} else { // check for jazz plugin midiapi support
				for (var n = 0; navigator.plugins.length > n; n ++) {
					var plugin = navigator.plugins[n];
					if (plugin.name.indexOf('Jazz-Plugin') >= 0) {
						supports['webmidi'] = true;
					}
				}
			}
		}

		/// check whether <audio> tag is supported
		if (typeof(Audio) === 'undefined') {
			return onsuccess({});
		} else {
			supports['audiotag'] = true;
		}

		/// check for webaudio api support
		if (window.AudioContext || window.webkitAudioContext) {
			supports['webaudio'] = true;
		}

		/// check whether canPlayType is supported
		var audio = new Audio();
		if (typeof(audio.canPlayType) === 'undefined') {
			return onsuccess(supports);
		}

		/// see what we can learn from the browser
		var vorbis = audio.canPlayType('audio/ogg; codecs="vorbis"');
		vorbis = (vorbis === 'probably' || vorbis === 'maybe');
		var mpeg = audio.canPlayType('audio/mpeg');
		mpeg = (mpeg === 'probably' || mpeg === 'maybe');
		// maybe nothing is supported
		if (!vorbis && !mpeg) {
			onsuccess(supports);
			return;
		}

		/// or maybe something is supported
		if (vorbis) canPlayThrough('audio/ogg;base64,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');
		if (mpeg) canPlayThrough('audio/mpeg;base64,/+MYxAAAAANIAUAAAASEEB/jwOFM/0MM/90b/+RhST//w4NFwOjf///PZu////9lns5GFDv//l9GlUIEEIAAAgIg8Ir/JGq3/+MYxDsLIj5QMYcoAP0dv9HIjUcH//yYSg+CIbkGP//8w0bLVjUP///3Z0x5QCAv/yLjwtGKTEFNRTMuOTeqqqqqqqqqqqqq/+MYxEkNmdJkUYc4AKqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq');

		/// lets find out!
		var time = (new Date()).getTime(); 
		var interval = window.setInterval(function() {
			var now = (new Date()).getTime();
			var maxExecution = now - time > 5000;
			if (!pending || maxExecution) {
				window.clearInterval(interval);
				onsuccess(supports);
			}
		}, 1);
	};

})(MIDI);