function selectimage() {
        if (niftyplayer('niftyPlayer1').getState() == 'playing') {
          document.getElementById("sound_button").style.backgroundImage = "url(images/toggle_sound_off.gif)";
        } else {
          document.getElementById("sound_button").style.backgroundImage = "url(images/toggle_sound_on.gif)";
        }
      }

      function togglesound()
      {
        niftyplayer('niftyPlayer1').playToggle();
        selectimage();
      }

      niftyplayer('niftyPlayer1').registerEvent('onSongOver', 'selectimage()');