<html>
  <body>
    <iframe id="player_frame" type="text/html" width="640" height="390"
        src=""
        frameborder="0"></iframe>
    <br>
    <script>
      function play(video_url) {
        document.getElementById('player_frame').src = video_url;
     }
      var tag = document.createElement('script');
      tag.src = "http://www.youtube.com/iframe_api";
      var firstScriptTag = document.getElementsByTagName('script')[0];
      firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);
      var player;
      function onYouTubeIframeAPIReady() {
        new YT.Player('player_frame', {
          events: {
            'onReady': onPlayerReady,
          }
        });
      }
      function onPlayerReady(event) {
        player = event.target;
        player.playVideo();
      }
    </script>
  </body>
</html>