public static Image ResizeImage( Image img, int MaxX, int MaxY )
{
  if( img == null )
    return null;
  Image RetVal = null;
  double TeilerX = ((double)img.Width)/(double)MaxX;
  double TeilerY = ((double)img.Height)/(double)MaxY;
  if( TeilerX > TeilerY )
  {
    RetVal = img.GetThumbnailImage((int)(img.Width/TeilerX),(int)( _
      img.Height/TeilerX),null,IntPtr.Zero);
  }
  else
  {
    RetVal = img.GetThumbnailImage((int)(img.Width/TeilerY),(int)( _
      img.Height/TeilerY),null,IntPtr.Zero);
  }
  return RetVal;
}