youtube.test.html

<!DOCTYPE html>
<html>
  <body>
    <!-- 1. The <iframe> (and video player) will replace this <div> tag. -->
    <div id="player1"></div>
    <div id="player2"></div>

    <script>
      // 2. This code loads the IFrame Player API code asynchronously.
      var tag = document.createElement('script');

      tag.src = "https://www.youtube.com/iframe_api";
      var firstScriptTag = document.getElementsByTagName('script')[0];
      firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);

      // 3. This function creates an <iframe> (and YouTube player)
      //    after the API code downloads.
      var player1;
      var player2;
      function onYouTubeIframeAPIReady() {
        player1 = new YT.Player('player1', {
          height: '390',
          width: '640',
          videoId: 'UOQ40DqGZ5A',
          events: {
            'onReady': onPlayerReady,
            'onStateChange': onPlayerStateChange
          }
        });
        player2 = new YT.Player('player2', {
          height: '390',
          width: '640',
          videoId: 'UOQ40DqGZ5A',
          events: {
            'onReady': onPlayerReady,
            'onStateChange': onPlayerStateChange
          }
        });
      }


      // 4. The API will call this function when the video player is ready.
      function onPlayerReady(event) {
        event.target.playVideo();
      }

      // 5. The API calls this function when the player's state changes.
      //    The function indicates that when playing a video (state=1),
      //    the player should play for six seconds and then stop.
      var done = false;
      function onPlayerStateChange(event) {
        if (event.data == YT.PlayerState.PLAYING && !done) {
          setTimeout(stopVideo, 6000);
          done = true;
        }
      }
      function stopVideo() {
        player1.stopVideo();
        player2.stopVideo();
      }
    </script>
  </body>
</html>