<% @ Import NameSpace="System" %>
<% @ Import NameSpace="System.Drawing" %>
<script language=JScript runat=Server>
private function Page_Load(Sender:Object, e:EventArgs)
{
var myBitmap : Bitmap = new Bitmap(Server.MapPath("YourFile.jpg"));
Response.Write("Width : " + myBitmap.Width + " Height : " + myBitmap.Height);
myBitmap.Dispose();
}
</script>
<form runat=server>
</form>