asp 图片切换代码 怎么修改这个！

<script>
var widths=260;
var heights=200;
var counts=4;
img1=new Image ();img1.src='images/01.gif'
img2=new Image ();img2.src='images/02.gif'
img3=new Image ();img3.src='images/03.gif'
img4=new Image ();img4.src='images/04.gif'
//img5=new Image ();img5.src='images/05.gif'
url1=new Image ();url1.src='http://www.sina.com.cn'
url2=new Image ();url2.src='#'
url3=new Image ();url3.src='#'
url4=new Image ();url4.src='#'
//url5=new Image ();url5.src='#'
var nn=1;
var key=0;
function change_img()
{if(key==0){key=1;}
else if(document.all)
{document.getElementById("pic").filters[0].Apply();document.getElementById("pic").filters[0].Play(duration=2);}
eval('document.getElementById("pic").src=img'+nn+'.src');
eval('document.getElementById("url").href=url'+nn+'.src');
document.getElementById("url").target='_blank';

for (var i=1;i <=counts;i++){document.getElementById("xxjdjj"+i).className='axx';}
document.getElementById("xxjdjj"+nn).className='bxx';
nn++;if(nn>counts){nn=1;}
tt=setTimeout('change_img()',3000);}
function changeimg(n){nn=n;window.cle