function popup(file,w,h) {
	sW = (window.screen.width/2) - (500/2 + 10);
  sH = (window.screen.height/2) - (500/2 + 20);
  var attributi = "width="+w+",height="+h+",top="+sH+", left="+sW+",toolbar=no,location=no,menubar=no, resizable=no, scrollbars=no";
	var percorso=file.split("/");
	file_name='immagini/'+percorso[percorso.length-1].substr(0,3)+'img'+percorso[percorso.length-1].substr(7);
	mywin=window.open("zoom.html?"+file_name,'img',attributi);
	mywin.focus();
}