function pref()
{
urll='pref.php';
 w=window.open("", "pref",
   "height=200,width=400,status=no,scrollbar=no,toolbar=no,resizable=no,menubar=no,left="+(screen.availWidth/2-250)+",top="+(screen.availHeight/2-100));
 w.location=urll;
 w.focus();
 return;
};
function DopImF(tp,nid,id,ht,wt)
{
kf=wt/ht;
MaxX=700;
MaxY=750;
if(wt>MaxX){x=MaxX;}else{x=wt;};
if(ht>MaxY){y=MaxY;}else{y=ht;};
if((x/y)<kf) 
 {
 y=x/kf;
 }
 else if((x/y)>kf)
 {
 x=y*kf;
 };
lpos=screen.availWidth/2-x/2;
tpos=screen.availHeight/2-y/2;

urll='DopImF.php?tp='+tp+'&nid='+nid+'&id='+id;
 w=window.open("", "DopImF",
   "height="+y+",width="+x+",status=no,scrollbar=no,toolbar=no,resizable=1,menubar=no,left="+lpos+",top="+tpos);
 w.location=urll;
 w.focus();
 return;
};