js 水平滚动代码 有大用

<div id="demo" style="overflow:hidden;width:550px;border:1px solid red;">
<table cellpadding="1" cellspacing="1">
 <tr>
 <td valign="top" id="marquePic1">
 <table width="100%" border="0" cellspacing="0" cellpadding="0">
 <tr align="center">
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 <td><img src="img.gif" width="70" height="70" border="0"></td>
 </tr>
 </table>
 </td>
 <td id="marquePic2" valign="top"></td>
 </tr>
</table>
</div>
<script language="javascript">
var speed=30;
marquePic2.innerHTML=marquePic1.innerHTML;

value = 0;
function Marquee(){
 if(value >=marquePic1.scrollWidth){//demo向左滚动的距离,, 如果大于marquePic1的宽度
 demo.scrollLeft=0;

 value =0;
 }else{

  value = value+1;
 demo.scrollLeft = value ;
 }
}
var MyMar=setInterval(Marquee,speed);
demo.onmouseover=function() {clearInterval(MyMar);MyMar=null;}
demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}
</script>