var totalSet = 15;
    var currentSet = 0;    
    var chosenImage = '';
    
    function setStart(item){
		chosenImage = item;
    }
  
	function hide(item){
	
      if ((document.getElementById(item).style.visibility == 'visible'))
        {
            document.getElementById(item).style.visibility = 'hidden';
        }
    }
    
    function show(item){
	  
	  if ((chosenImage != item || chosenImage == '') && item != 'subMenu')
		{
			hide (chosenImage);
		}  

      if ((document.getElementById(item).style.visibility == 'hidden'))
        {
            document.getElementById(item).style.visibility = 'visible';
        }
        chosenImage = item;
    }
    
    function underline(linkId){
    
        if (document.getElementById(linkId).style.textDecoration == 'underline')
        {
            document.getElementById(linkId).style.textDecoration = 'none'
        }
        else
        {
            document.getElementById(linkId).style.textDecoration = 'underline'
        }
    }
  
    function changeImage(){
    
		if (currentSet == 0)
		{
			var cimagename = 's1i';
			var pimagename = 's' + totalSet / 3 + 'i';
			currentSet = 2;
		}
		else
		{
			var cimagename = 's' + currentSet.toString() + 'i';
			var pimagename = 's' + (currentSet - 1).toString() + 'i';
			currentSet = currentSet + 1;
			
			if (currentSet > totalSet / 3)
			{
				currentSet = 0;
			}
		}

		if (document.getElementById(cimagename + '1.png') != null)
		{
			document.getElementById(cimagename + '1.png').style.visibility = 'visible';
			document.getElementById(cimagename + '2.png').style.visibility = 'visible';
			document.getElementById(cimagename + '3.png').style.visibility = 'visible';
		}
		else
		{
			document.getElementById(cimagename + '1rev.png').style.visibility = 'visible';
			document.getElementById(cimagename + '2rev.png').style.visibility = 'visible';
			document.getElementById(cimagename + '3rev.png').style.visibility = 'visible';
		}
		if (document.getElementById(pimagename + '1.png') != null)
		{
			document.getElementById(pimagename + '1.png').style.visibility = 'hidden';
			document.getElementById(pimagename + '2.png').style.visibility = 'hidden';
			document.getElementById(pimagename + '3.png').style.visibility = 'hidden';
		}
		else
		{
			document.getElementById(pimagename + '1rev.png').style.visibility = 'hidden';
			document.getElementById(pimagename + '2rev.png').style.visibility = 'hidden';
			document.getElementById(pimagename + '3rev.png').style.visibility = 'hidden';
		}
		trackTime();
    }
    
    function trackTime(){
		var t=setTimeout("changeImage()",5000);
    }