var pre='deco';
var ext='jpg';
var nbImg=5;
var delai=8000;
var i=2;


function chgImg()
{
  if (document.getElementById) o = document.getElementById('diapo');
  else if (document.images) o = document.images.diapo;
        
  if (o) {
    if (o.filters) o.filters[0].apply();
    o.src = 'img/'+pre+i+'.'+ext;
    if (o.filters) o.filters[0].play();
  }        
        
  i = i % nbImg + 1;
  
  setTimeout('chgImg()',delai);
}