图片广告切换问题。

大家好！！
下面是一段代码：
$(document).ready(function() {
$("img#advsheadlbpic_0").show();
setInterval("$().advsHeadLbRoll()", 5000);
(function($){
$.fn.advsHeadLbRoll = function(){
var rollobj=$(".advsheadlbpic");
var rolltotal=parseInt(rollobj.size())-1;
var nextId,nowId;
$("img.advsheadlbpic").each(function(){
if(this.style.display=='block' || this.style.display=='inline'){
nowId=parseInt(this.id.substr(14));
if(nowId>=rolltotal){
nextId=0;
}else{
nextId=nowId+1;
}
}
});
$("img#advsheadlbpic_"+nextId).fadeIn('slow').show('slow');
$("img#advsheadlbpic_"+nowId).fadeOut('slow').hide();
};
})(jQuery);
}); 
在 .aspx* 调用：<head id="Head1" runat="server">
    <title>首页</title>
       <script  src ="/js/advsheadlb.js" type ="text/javascript" ></script>
   
</head>在div里要显示的图片广告： <div id="advsheadlb">
                                    <img id="advsheadlbImages_0" class="advsheadlbpic" border="0" src="Images/1285659686.jpg"alt =""/>
                                        
                                    <img id="advsheadlbImages_1" class="advsheadlbpic" border="0" src="Images/1285659690.jpg" alt =""/>
                                        
                                </div>
页面运行的时候图片不显示？ 以上代码哪里出错 了呢？求解！！！！！谢谢。。