OpenCV 改变图像的对比度和亮度

 1 #include <opencv2/core/core.hpp>
 2 #include <opencv2/highgui/highgui.hpp>
 3 #include <iostream>
 4 
 5 using namespace std;
 6 using namespace cv;
 7 
 8 double alpha; /**< 控制对比度 */
 9 int beta;  /**< 控制亮度 */
10 
11 int main( int argc, char** argv )
12 {
13     /// 读入用户提供的图像
14     Mat image = imread( argv[1] );
15     Mat new_image = Mat::zeros( image.size(), image.type() );
16 
17     /// 初始化
18     cout << " Basic Linear Transforms " << endl;
19     cout << "-------------------------" << endl;
20     cout << "* Enter the alpha value [1.0-3.0]: ";
21     cin >> alpha;
22     cout << "* Enter the beta value [0-100]: ";
23     cin >> beta;
24 
25     /// 执行运算 new_image(i,j) = alpha*image(i,j) + beta
26     for( int y = 0; y < image.rows; y++ )
27     {
28         for( int x = 0; x < image.cols; x++ )
29         {
30             for( int c = 0; c < 3; c++ )
31             {
32                 new_image.at<Vec3b>(y,x)[c] = saturate_cast<uchar>( alpha*( image.at<Vec3b>(y,x)[c] ) + beta );
33             }
34         }
35     }
36 
37     /// 创建窗口
38     namedWindow("Original Image", 1);
39     namedWindow("New Image", 1);
40 
41     /// 显示图像
42     imshow("Original Image", image);
43     imshow("New Image", new_image);
44 
45     /// 等待用户按键
46     waitKey();
47     return 0;
48 }