为什么显示时，每张图片一开始会变很宽，然后过1-2秒才正常。求高手解答
为什么显示时，每张图片一开始会变很宽，然后过1-2秒才正常。
程序中是有个压缩图片的过程，如800*533会压为255＊166， 

从左到右的滚动，滚动区的高是300，宽是1024，每张，图会一开始变很宽，我想一开始就是压缩图片的格式


<script language="JavaScript"> 
<!-- 
var flag=false; 
function DrawImage(ImgD){ 
 var image=new Image(); 
 image.src=ImgD.src; 
 if(image.width>0 && image.height>0){ 
  flag=true; 
  if(image.width/image.height>= 105/80){ 
  if(image.width>105){
  ImgD.width=250; 
  ImgD.height=(image.height*250)/image.width; 
  }else{ 
  ImgD.width=image.width;
  ImgD.height=image.height; 
  } 
  ImgD.alt="点击查看详细信息..."; 
  } 
  else{ 
  if(image.height>80){
  ImgD.height=250; 
  ImgD.width=(image.width*250)/image.height; 
  }else{ 
  ImgD.width=image.width;
  ImgD.height=image.height; 
  } 
  ImgD.alt="点击查看详细信息..."; 
  } 
 }
}
//--> 
</script> 
<%
Const Photo_img=6  
set rs_Photo=server.createobject("adodb.recordset")
sqltext="select top " & Photo_img & " * from Photo where Passed=True and Newproduct=true order by UpdateTime desc"
rs_Photo.open sqltext,conn,1,1
if not rs_Photo.EOF then%>
<div align='center' id='demo0' style='overflow:hidden;height:300px;width:1004px'><!--滚动区-->
<table align='center' cellpadding='0' cellspace='0' border='0'>
<tr>
<td id='demo11' valign='top'>
<%
while not rs_Photo.EOF
fileExt=lcase(getFileExtName(rs_Photo("DefaultPicUrl")))
%>
<td align='center'>
<TABLE width="100%" border=0 align=center cellPadding=0 cellSpacing=0>
<TR>
 
<TD width="815" height="200" align="center" bgcolor="#E9E9E9">
<a href='PhotoShow.asp?ID=<%=rs_Photo("ID")%>' target=_blank title='<%=rs_Photo("title")%>'>
<%if fileext="jpg" or fileext="bmp" or fileext="png" or fileext="gif" then%>
<img src="<%if rs_Photo("DefaultPicUrl")="" then%>Img/nopic.gif<%else%><%=rs_Photo("DefaultPicUrl")%><%end if%>" alt="<%=rs_Photo("title")%>" width="815" height="200" border="0" onload="javascript:DrawImage(this);">
<%else
if fileext="swf" then%>


<%end if
end if%></a>

</TD>
<TD colspan=3 align=center height=50 valign='top'>
<a href='PhotoShow.asp?ID=<%=rs_Photo("ID")%>' target=_blank title='<%=rs_Photo("title")%>'><%=cutstr(rs_Photo("title"),50)%></a>
</TD>
<TD>　</TD>
</TR>
</TABLE>
</td>
<%
rs_Photo.MoveNext
wend
%>
</tr>
</table>
</td>
<td id=demo22 valign=top></td>
</tr>
</table>
</div>
  <%if Photo_img >5 then%>
<script>
var Picspeed1=5
demo22.innerHTML=demo11.innerHTML
function Marquee2(){
if(demo22.offsetWidth-demo0.