OpenCV 动态调整图像对比度、亮度

//全局变量声明
static void on_ContrasAndBright(int, void*);int g_nContrastValue; //对比度值
int g_nBrightValue; //亮度值
Mat g_srcImage, g_dstImage;void Test()
{//读取输入图像g_srcImage = imread("img.jpg");g_dstImage = Mat::zeros(g_srcImage.size(), g_srcImage.type());//设定对比度和亮度的初值g_nContrastValue = 80;g_nBrightValue = 80;//创建效果图窗口namedWindow("效果图窗口", 0);//创建轨迹条createTrackbar("对比度", "效果图窗口", &g_nContrastValue, 300, on_ContrasAndBright);createTrackbar("亮度", "效果图窗口", &g_nBrightValue, 200, on_ContrasAndBright);//进行回调函数初始化on_ContrasAndBright(g_nContrastValue, 0);on_ContrasAndBright(g_nBrightValue, 0);//按下“q”键，程序退出while (char(waitKey(1)) != 'q'){}
}//on_ContrastAndBright()函数
//改变图像对比度和亮度值的回调函数
static void on_ContrasAndBright(int, void*)
{//创建窗口namedWindow("原始图窗口", 0);//3个循环，执行运算g_dstImage(i,j)=a*g_srcImage(i,j)+bfor (int y = 0; y < g_srcImage.rows; y++){for (int x = 0; x < g_srcImage.cols; x++){for (int c = 0; c < 3; c++){g_dstImage.at<Vec3b>(y, x)[c] = saturate_cast<uchar>((g_nContrastValue*0.01)*(g_srcImage.at<Vec3b>(y, x)[c]) + g_nBrightValue);}}}//显示图像imshow("原始图窗口", g_srcImage);imshow("效果图窗口", g_dstImage);
}