检测多媒体

test.video.audio.js

tests['video'] = function() {
    var elem = document.createElement('video'),
        bool = false;

    // IE9 Running on Windows Server SKU can cause an exception to be thrown, bug #224
    try {
        if ( bool = !!elem.canPlayType ) {
            bool      = new Boolean(bool);
            bool.ogg  = elem.canPlayType('video/ogg; codecs="theora"')      .replace(/^no$/,'');

            // Without QuickTime, this value will be `undefined`. github.com/Modernizr/Modernizr/issues/546
            bool.h264 = elem.canPlayType('video/mp4; codecs="avc1.42E01E"') .replace(/^no$/,'');

            bool.webm = elem.canPlayType('video/webm; codecs="vp8, vorbis"').replace(/^no$/,'');
        }

    } catch(e) { }

    return bool;
};

tests['audio'] = function() {
    var elem = document.createElement('audio'),
        bool = false;

    try {
        if ( bool = !!elem.canPlayType ) {
            bool      = new Boolean(bool);
            bool.ogg  = elem.canPlayType('audio/ogg; codecs="vorbis"').replace(/^no$/,'');
            bool.mp3  = elem.canPlayType('audio/mpeg;')               .replace(/^no$/,'');

            // Mimetypes accepted:
            //   developer.mozilla.org/En/Media_formats_supported_by_the_audio_and_video_elements
            //   bit.ly/iphoneoscodecs
            bool.wav  = elem.canPlayType('audio/wav; codecs="1"')     .replace(/^no$/,'');
            bool.m4a  = ( elem.canPlayType('audio/x-m4a;')            ||
                          elem.canPlayType('audio/aac;'))             .replace(/^no$/,'');
        }
    } catch(e) { }

    return bool;
};