function NeuesFenster(a){
  var Fenster = window.open(a.href, '', '');
  return false;
}

function Popup(Url, Titel, Breite, Hoehe, scrollbars){
  if(!scrollbars){
    scrollbars = 'yes';
  }

  var BreiteMax = screen.availWidth ? (screen.availWidth - 100) : 800;
  var HoeheMax = screen.availHeight ? (screen.availHeight - 100) : 600;

  if(Breite > BreiteMax){
    Breite = BreiteMax;
  }

  if(Hoehe > HoeheMax){
    Hoehe = HoeheMax;
  }

  var PosLeft = screen.availWidth ? Math.round((screen.availWidth-Breite)/2) : 0;
  var PosTop = screen.availHeight ? Math.round((screen.availHeight-Hoehe)/2) : 0;

  var Parameter = 'scrollbars='+scrollbars+',toolbar=0,location=no,directories=no,status=0,menubar=no,resizable=yes,copyhistory=no,width='+Breite+',height='+Hoehe+',screenX='+PosLeft+',screenY='+PosTop+',top='+PosTop+',left='+PosLeft;
  var Fenster = window.open(Url, '', Parameter);
  Fenster.focus();
  Fenster = null;
}


function Bild(UrlRoot, Dateiname, alt, title, class_){
  Popup(UrlRoot+'/Bild.php?Dateiname='+Dateiname+'&alt='+alt+'&title='+title+'&class='+class_,'', 400, 300);
}