C#图像亮度调式与伪彩色图的处理

如图，左图是效果，右图是原理，右图X轴代表图像一个像素点的灰度，Y轴代表RGB三个颜色对应的伪彩色图颜色。代码如下：

for (int y = 0; y < height; y++)

                {

                    for (int x = 0; x < width; x++)

                    {

                        Color c = bmp.GetPixel(x, y);

                        int R = c.R; int G = c.G; int B = c.B;

                        byte temp = (byte)(B * 0.114 + G * 0.587 + R * 0.299);

                        if (temp >= 0 && temp <= 63)

                        {

                            bmp.SetPixel(x, y, Color.FromArgb(0, (byte)(4 * temp), (byte)255));

                        }

                        if (temp >= 64 && temp <= 127)

                        {

                            bmp.SetPixel(x, y, Color.FromArgb(0, 255, (byte)(510 - 4 * temp)));

 

                        }

                        if (temp >= 128 && temp <= 191)

                        {

                            bmp.SetPixel(x, y, Color.FromArgb((byte)(4 * temp - 510), 255, 0));

                        }

                        if (temp >= 192 && temp <= 255)

                        {

                            bmp.SetPixel(x,y, Color.FromArgb(255, (byte)(1022 - 4 * temp),0));

                        }

                    }

}

图像亮度调整：for (int y = 50; y < 100; y++)

                    {

                        for (int x = 50; x < 100; x++)

                        {

                            // 处理指定位置像素的亮度

                            Color c = b.GetPixel(x, y);

                            int R = c.R; int G = c.G; int B = c.B;

                            R = R + degree; if (R > 255) R = 255;

                            G = G + degree; if (G > 255) G = 255;

                            B = B + degree; if (B > 255) B = 255;

                            b.SetPixel(x, y, Color.FromArgb(R, G, B));

                        }

                    }//其中degree是亮度阶梯度