var Plaatjes = new Array();
Plaatjes[0] = 'dia1.jpg';
Plaatjes[1] = 'dia2.jpg';
MM_preloadImages('images/' + Plaatjes[0],
                 'images/' + Plaatjes[1]);

var teller = 0;

function cycle() {
  var speed = 20;
  var timer = 0;

  document.getElementById('diadiv').style.backgroundImage = 'url(images/' + Plaatjes[teller] + ')';
  changeOpac(0);

  teller++;
  if (teller == Plaatjes.length) {teller = 0;}
  dia.src = 'images/' + Plaatjes[teller];
  for (i = 0; i <= 100; i++) { 
    setTimeout('changeOpac(' + i + ')', (timer * speed));
    timer++;
  } 

  setTimeout("cycle()",5000);
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

//change the opacity for different browsers 
function changeOpac(opacity) { 
    var object = document.getElementById('dia').style; 
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
}