Edit in JSFiddle

<h3>Detect Video Formats with Modernizr tests (with JS control)<br/>
<a href="www.aureliomerenda.com/detect-video-formats-support-modernizr-tests/">www.aureliomerenda.com/detect-video-formats-support-modernizr-tests/</a></h3>
<br/>
<p>Your browser supports:</p>
<p><b>OGG:</b> <span id="oggsupport"></span></p>
<p><b>H264:</b> <span id="h264support"></span></p>
<p><b>WEBM:</b> <span id="webmsupport"></span></p>
/****** MODERNIZR TEST *******/

Modernizr.addTest('videoogg', function(){
     var elem = document.createElement('video'),
          bool = false;
     try {
          bool = !!elem.canPlayType;
          if ( bool ) {
               bool = new Boolean(bool);
               bool.ogg = elem.canPlayType('video/ogg; codecs="theora"').replace(/^no$/,'');
               if(bool.ogg == "maybe" || bool.ogg == "probably"){
                    bool = true;
               } else {
                    bool = false;
               }
          }
     } catch(e) { }
     return bool;
});


Modernizr.addTest('videoh264', function(){
     var elem = document.createElement('video'),
          bool = false;
     try {
          bool = !!elem.canPlayType;
          if ( bool ) {
               bool = new Boolean(bool);
               bool.h264 = elem.canPlayType('video/mp4; codecs="avc1.42E01E"').replace(/^no$/,'');
               if(bool.h264 == "maybe" || bool.h264 == "probably"){
                    bool = true;
               } else {
                    bool = false;
               }
          }
     } catch(e) { }
      return bool;
});


Modernizr.addTest('videowebm', function(){
     var elem = document.createElement('video'),
          bool = false;
      try {
          bool = !!elem.canPlayType;
          if ( bool ) {
               bool = new Boolean(bool);
               bool.webm = elem.canPlayType('video/webm; codecs="vp8, vorbis"').replace(/^no$/,'');
               if(bool.webm == "maybe" || bool.webm == "probably"){
                    bool = true;
               } else {
                    bool = false;
               }
          }
     } catch(e) { }
      return bool;
});

/****** RUN *******/

var oggsupport = Modernizr.videoogg ? "YES" : "NO";
var h264support = Modernizr.videoh264 ? "YES" : "NO";
var webmsupport = Modernizr.videowebm ? "YES" : "NO";
$("#oggsupport").text(oggsupport);
$("#h264support").text(h264support);
$("#webmsupport").text(webmsupport);