请大家帮帮忙，这个网站这样的效果怎么实现？

Question

<SCRIPT language=JavaScript>
var imgUrl=new Array();
var imgLink=new Array();
var adNum=0;
imgLink[1]="/Article/";
imgUrl[1]="http://www.100wa.com/news/img/1.jpg";
imgLink[2]="/vod/";
imgUrl[2]="http://www.100wa.com/news/img/2.jpg";
imgLink[3]="/mm/";
imgUrl[3]="http://www.100wa.com/news/img/3.jpg";
imgLink[4]="/joke/";
imgUrl[4]="http://www.100wa.com/news/img/4.jpg";
var imgPre=new Array();
var j=0;
for (i=1;i<=4;i++) {
//if( (imgUrl[i]!="") && (imgLink[i]!="") ) {
if(imgUrl[i]!="") {
if (imgLink[i]==""){
 imgLink[i]="http://www.5aie.com";
}
j++;
} else {
break;
}
}
function playTran(){
if (document.all)
imgInit.filters.revealTrans.play();
}
var key=0;
var adNum=0;
function nextAd(){
if(adNum<j)adNum++ ;
else adNum=1;

if( key==0 ){
key=1;
} else if (document.all){
imgInit.filters.revealTrans.Transition=6;
imgInit.filters.revealTrans.apply();
                   playTran();
}
document.images.imgInit.src=imgUrl[adNum];
theTimer=setTimeout("nextAd()", 6000);
}
function goUrl(){
jumpUrl=imgLink[adNum];
jumpTarget="_blank";
if (jumpUrl != ""){
if (jumpTarget != "") 
window.open(jumpUrl,jumpTarget);
else
location.href=jumpUrl;
}
}
</SCRIPT>