<video id="video1" controls="controls"> <source src="/statics/demosource/mov_bbb.mp4" type="video/mp4"> <source src="/statics/demosource/mov_bbb.ogg" type="video/ogg"> Your browser does not support HTML5 video. </video> <script> myVid=document.getElementById("video1"); myVid.addEventListener("loadstart", function() { alert("Starting to load video"); } ); </script> <p>Video courtesy of <a href="http://www.bigbuckbunny.org/" target="_blank">Big Buck Bunny</a>.</p>