//----------------------------
  // Die eigendliche Bearbeitung ist hier
  //----------------------------

  function BearbeiteEinBild(cImageName)
  {
   var result=false;
   if( FF_LoadExif(cImageName)  && FF_HasExif() )
    {
      if (   (FF_GetExifTag("Model") == "Canon EOS 400D DIGITAL")
          && (FF_GetExifTag("FocalLengthIn35mmFilm") == "" )
         )
      {
        FF_SetExifTag("FocalLengthIn35mmFilm",  Math.round((1.61 * FF_GetExifTagAdvanced("FocalLength") ),0) );
           FF_SaveExif(cImageName);
           result=true;
      }
    }
    return result;
  }

  //======================================================================================

  function Shorten(s, maxlen)
  {
     var r = new String(s);
     if(  r.length> maxlen )
          r = r.substring(0,5) + "..." + r.substring( r.length-maxlen , r.length);
     return r;
  }

  //======================================================================================
  // Main
  //======================================================================================
  function Main()
  {
  var dlg = makemaindialog();
  var nCurrent;
  var cImageName="";
  var NumImages = FF_GetImageCount();
  var doneImmages=0; // bis zum evtl. abbruch
  var aborted=false;
  var r;

  FF_SetProgressText(0, NumImages,"");
  FF_SetControl(dlg,"aktfile","");
  try
   {
    FF_OpenDialog(dlg);
    for(r=""; ; )
    {
     r=FF_ShowDialog(dlg);
     if (r=="CANCEL") break;
     if (r=="Start") break;
    }
    if (r=="Start")
    {
     for ( nCurrent = 0 ; nCurrent < NumImages ; nCurrent++ )
     {
      var key=FF_CheckKey();
      if (key==27)
        {
         if (FF_MessageBox("Script abbrechen?",4)==6)
           {
            aborted=true;
            break;
           }
        }
      cImageName    =  FF_getImageName(nCurrent);
      FF_SetProgressText(nCurrent, NumImages,cImageName);
      FF_SetControl(dlg,"prog",(100/NumImages*(nCurrent+1)));
      var msg = ""  + (nCurrent+1)+" von "+NumImages + "  " + Shorten(cImageName,40);
      FF_SetControl(dlg,"aktfile",msg);
      FF_LoadThumb(cImageName);
      FF_SetControl(dlg,"vorschau",0);
      FF_RefreshDialog(dlg);
       // Aktion.....
      if( BearbeiteEinBild(cImageName) )
         doneImmages++;
    }  // for
    FF_RefreshDialog(dlg);
    } // if
   } // try
   catch(e)
   {
     var msg="Script-Fehler:\r\n";
     msg = msg + e + "\r\n";
     msg = msg + "Fehler Nr.: 0x" + (e.number & 0x1FFFFFFF).toString(16).toUpperCase() +"\r\n";
     msg = msg + e.description+"\r\n\r\n";
     msg=msg+"Aktuelle Datei:\r\n"+cImageName;
     FF_Messagebox(msg,16);
    }
   finally
   {
    FF_CloseDialog(dlg);
   }

   if( r=="Start")
   {
     if (aborted)
        msg="Abbruch"
     else msg="Fertig";
     FF_MessageBox("Selektierte Bilder: "+NumImages+"\r\n"+
                    "davon bearbeitet  : "+doneImmages+"\r\n"+msg,64);
   }
  }