var aImages=new Array();
var autoStart=true;
var iActiveLayer=1;
var iCurrentImage=0;
var http=createRequestObject();
var curImgSrc;

var am=new Array();
var af=new Array();
var as=new Array();
var sss;
var sDataPath;
var clickLink;
//setTimeout("preLoader()",1000);
//preLoader();
setTimeout("prepareSlideshow()","5000");


function preLoader() {
    var z=document.getElementById("topImg1").src;
    var filename=z.substr(0,z.lastIndexOf("."));
    var extension=z.substr(z.lastIndexOf("."));
    af.push(document.getElementById("topImg1").src);
    as.push(true);
	sendReq(af[iCurrentImage]);
	
    for(var i=1;i<=10;i++){
        var n=new Image();
        am.push(n);
        as.push(false);
        af.push(filename+i+extension)
        n.src=filename+i+extension;
        n.id="pic"+i;
        n.onload=imgLoaded;
    }
	sDataPath=z;
}
function imgLoaded(){
    var i=parseInt(this.id.substr(3));
    as[i]=true;
    updateLinks();
}
function updateLinks() {
    var e=document.getElementById("links");
    var sHTML="";
    for(var i=1;i<=10;i++){
        if(as[i]){
            sHTML=sHTML+" / "+"<a style='color:#CCCCCC;' href='javascript:gotoImage("+i+")'>"+(i+1)+"</a> ";
        }
    }
    if(sHTML!=""){
        sHTML="<a style='color:#CCCCCC;' href='javascript:gotoImage("+0+")'>1</a> "+sHTML;
    }
    e.innerHTML=sHTML;
}
function showImage(i){
    pauseSlide();
    document.getElementById("topImg2").style.display="none";
    document.getElementById("topImg1").style.display="inline";
    document.getElementById("topImg1").src=af[i];

}

function prepareSlideshow(){
    for(var i=0;i<=10;i++){
        if(as[i]){
            aImages.push(new Array(af[i],""));
        }
    } 
    if(aImages.length>1){   
        //initSlide();
   	    playSlide();
   	}
}


var t,s;
var iTransitionTime=2;
var iSlidePauseTime=5;
var bActive=false;
var iImageCount;

function initSlide() {
    iImageCount=aImages.length;
	iActiveLayer++;
	if(iActiveLayer==3)iActiveLayer=1;
	iCurrentImage++;
	if(iCurrentImage>aImages.length)iCurrentImage=0;
	document.getElementById("topImg"+iActiveLayer).src=aImages[iCurrentImage][0];
	document.getElementById("pc"+iActiveLayer).style.display="inline";
}
function transition() {
	if(t)t.stop();
	t=new Parallel();
	var ein=document.getElementById("pc"+iActiveLayer);
	var eout=document.getElementById("pc"+((iActiveLayer==1)?2:1));
	t.addChild(new OpacityTween(ein,Tween.strongEaseOut,0,100,iTransitionTime));
	t.addChild(new OpacityTween(eout,Tween.strongEaseOut,100,0,iTransitionTime));
	t.start();
	sendReq(curImgSrc);
	if(document.getElementById("progressbar")){
		document.getElementById("progressbar").style.display="none";
	}
	if(bActive){
		sss=setTimeout("loadNewImage("+iSlidePauseTime+")",iTransitionTime*1000);
	}
}
function loadNewImage(wait) {

		iActiveLayer++;
		if(iActiveLayer==3)iActiveLayer=1;
		iCurrentImage++;
		if(iCurrentImage==aImages.length)iCurrentImage=0;
		
		document.getElementById("pc"+iActiveLayer).style.display="none";
        document.getElementById("topImg"+iActiveLayer).onload=function() { try{this.setAttribute("complete",true)}catch(err){} }
		document.getElementById("topImg"+iActiveLayer).src=af[iCurrentImage];
		curImgSrc=af[iCurrentImage];
		sss=setTimeout("waitForImage()",wait*1000);
}
<!-- nyt Stort billede -->
var browser = navigator.appName;

				

function createRequestObject() {
	//alert(sDataPath)
    var ro;
	if (!window.XMLHttpRequest) {
//    if(browser == "Microsoft Internet Explorer"){
        ro = new ActiveXObject("Microsoft.XMLHTTP");
    }else{
        ro = new XMLHttpRequest();
    }
//  ro.onreadystatechange = handleResponse;
    return ro;
}
function sendReq(action) {
	var e = action;
	var sData = e.toString();
	var s1 = sData.indexOf("http");
	var s2 = sData.indexOf(".jpg");
	sData=sData.substring(s1,s2);
	sData=sData+"_zoom.jpg";
	clickLink=sData;
	//alert(action);
    if(browser == "Microsoft Internet Explorer"){
		http.open('POST', sData);
		http.setRequestHeader("Content-Length","1")
    }else{
		http.open('HEAD', sData);
		http.setRequestHeader("Content-Length","1")
    }
	
	http.onreadystatechange = handleResponse;
    http.send(null);
}
function initEventHandlers() {
	preLoader();
}
function handleResponse() {
	if(http.readyState == 4){
		//alert(http.status)
		if(http.status == 404) {
			clickLink="";
			document.getElementById("zoomGrap").style.display="none";
			document.getElementById("topImg1").style.cursor="default";
			document.getElementById("topImg2").style.cursor="default";
			document.getElementById("topImg1").onclick="";
			document.getElementById("topImg2").onclick="";
			document.getElementById("magnify").style.cursor="default";
			document.getElementById("magnify").onclick="";
		} else {
			document.getElementById("zoomGrap").style.display="inline";
			document.getElementById("topImg1").style.cursor="pointer";
			document.getElementById("topImg2").style.cursor="pointer";
			document.getElementById("topImg1").onclick=showBigImage;
			document.getElementById("topImg2").onclick=showBigImage;
			document.getElementById("magnify").style.cursor="pointer";
			document.getElementById("magnify").onclick=showBigImage;
		}
	}
}

function showBigImage() {
	Lightbox.show(clickLink);
}

if(document.addEventListener){ // FF, NS 
	document.addEventListener("DOMContentLoaded", initEventHandlers, false); 
} else { // IE
	window.attachEvent("onload", initEventHandlers); 
}
<!-- nyt Stort billede slut-->

function waitForImage() {
	if(document.getElementById("progressbar")){
		document.getElementById("progressbar").style.display="inline";
	}
	if(document.getElementById("topImg"+iActiveLayer).complete){
		document.getElementById("pc"+iActiveLayer).style.display="inline";
		transition();
		//updateSelectors();
	}else{
		sss=setTimeout("waitForImage()",100);
	}
}
function pauseSlide() {
	bActive=false;
}
function playSlide() {
	if(aImages.length>0){
		bActive=true;
		loadNewImage(0.5);
	}
}
function gotoImage(n) {
	window.clearTimeout(sss);
	iCurrentImage=n-1;
	loadNewImage(0);
	bActive=false;
	if(document.getElementById("playinfo")){
		document.getElementById("playinfo").src="gfx/gal_pause.gif";
	}
}
function activateSlide() {
	window.clearTimeout(s);
	bActive=true;
	loadNewImage(0);
	if(document.getElementById("playinfo")){
		document.getElementById("playinfo").src="gfx/gal_play.gif";
	}
}
function updateSelectors() {
	for(var a=0;a<iImageCount;a++){
		if(document.getElementById("imgsel_"+a)){
			document.getElementById("imgsel_"+a).src="gfx/gal_selector"+ ((a==iCurrentImage)?"_act":"") +".gif";
		}
	}
}