window.addEventListener?window.addEventListener("load",so_init,false):window.attachEvent("onload",so_init);

var d=document, imgs = new Array(), zInterval = null, nyni=0, i=0;

function so_init()
{
	if(!d.getElementById || !d.createElement)return;
	
	imgs = d.getElementById("head").getElementsByTagName("img");
	nyni = Math.round((imgs.length-1)*Math.random());
	imgs[nyni].style.display = "block";
	setTimeout("prejdi("+nyni+")",5000);
}

function prejdi(nyni)
{
	novy = Math.round((imgs.length-1)*Math.random());
	if (novy==nyni)
		{
			prejdi(nyni);
		}
	else
		{
			so_xfade(novy, nyni);
		}
}

function so_xfade(novy, nyni)
{
	nynipruh=.99-i;
	novypruh=i;
	imgs[novy].style.display = "block";
	setOpacity(imgs[nyni],nynipruh);
	setOpacity(imgs[novy],novypruh);
	if (i<.99)
		{
			i=i+.01;
			setTimeout("so_xfade("+novy+","+nyni+")",60);
		}
	else
		{
			i=0;
			imgs[nyni].style.display = "none";
			setTimeout("prejdi("+novy+")",5000);
		}
}

function setOpacity(obj,pruh)
{
	obj.style.opacity = pruh;
	obj.style.MozOpacity = pruh;
	obj.style.filter = "alpha(opacity=" + (pruh*100) + ")";
}