图片转黑白的简单办法

使用原像素点RGB的平均值即可

public Image BlackAndWhite(Image image)
        {
            int Height = image.Height;
            int Width = image.Width;
            Bitmap newPic = new Bitmap(Width,Height);
            Bitmap oldPic = (Bitmap)image;
            Color pixel;

            for (int x = 0; x < Width; x++)
            {
                for (int y = 0; y < Height; y++)
                {
                    pixel = oldPic.GetPixel(x, y);
                    int r, g, b, result = 0;
                    r = pixel.R;
                    g = pixel.G;
                    b = pixel.B;
                    result = (r + g + b) / 3;
                    newPic.SetPixel(x, y, Color.FromArgb(result,result,result));
                }
            }

            return newPic;
        }