private Bitmap outmap(Bitmap s1, Bitmap s2)

        {

            so = new Bitmap(s1.Width, s1.Height);

            for (int i = 0; i < s1.Width; i++)

            {

                for (int j = 0; j < s1.Height; j++)

                {

                    Color a = s1.GetPixel(i, j);

                    Color b = s2.GetPixel(i, j);

                    // 跟據(jù)你的合并要求, 計算這兩個color的合并

                    int red = (int)a.R * (255 - b.A) / 255 + b.A * b.R / 255;

                    if (red > 255) red = 255;

                    int green = (int)a.G * (255 - b.A) / 255 + b.A * b.G / 255;

                    if (green > 255) green = 255;

                    int blue = (int)a.B * (255 - b.A) / 255 + b.A * b.B / 255;

                    if (blue > 255) blue = 255;

                    Color c = Color.FromArgb(red, green, blue);

                    so.SetPixel(i, j, c);

                }

            }

            return so;

        }