internal static void Save(ref SaveWriter sw)
        {
            String r = "";

            foreach (var rec in areas)
            {
                r = r + rec.X.ToString() + ";" + rec.Y.ToString() + ";" + rec.Width.ToString() + ";" + rec.Height.ToString() + "\r\n";
            }
            sw.WriteLine(r.Length.ToString());
            sw.WriteLine(r);
        }