opencv学习之路（9）、对比度亮度调整与通道分离

一、对比度亮度调整

 #include<opencv2/opencv.hpp>
 using namespace cv;

 #define WIN_NAME "输出图像"
 Mat src,dst;
 int contrast=,bright=;

 void onChange(int,void*){
     for (int i = ; i < src.rows; i++)
     {
         for (int j = ; j < src.cols; j++)
         {
             //saturate_cast<uchar>    溢出保护：if(data<0) data=0;    if(data>255) data=255;
             dst.at<Vec3b>(i,j)[]=saturate_cast<uchar>(src.at<Vec3b>(i,j)[]*contrast*0.01+bright);
             dst.at<Vec3b>(i,j)[]=saturate_cast<uchar>(src.at<Vec3b>(i,j)[]*contrast*0.01+bright);
             dst.at<Vec3b>(i,j)[]=saturate_cast<uchar>(src.at<Vec3b>(i,j)[]*contrast*0.01+bright);
         }
     }
     imshow("原图",src);
     imshow(WIN_NAME,dst);
 }

 void main(){
     src=imread("E://1.jpg");
     dst=Mat::zeros(src.size(),src.type());
     //Mat::zeros();//将矩阵元素置为0
     //Mat::ones();//置1
     namedWindow(WIN_NAME,CV_WINDOW_AUTOSIZE);
     createTrackbar("对比度",WIN_NAME,&contrast,,onChange,);
     createTrackbar("亮  度",WIN_NAME,&bright,,onChange,);

     onChange(contrast,);//回调函数初始化
     onChange(bright,);

     waitKey();

 }

二、通道分离与合并

 #include<opencv2/opencv.hpp>
 using namespace cv;

 void main(){
     Mat img=imread("E://2.jpg");
     Mat dst;
     vector<Mat>channels;//定义Mat类型的向量

     split(img,channels);//通道分离
     Mat blue=channels.at();
     Mat green=channels.at();
     Mat red=channels.at();

     threshold(blue,blue,,,THRESH_BINARY);//二值化：大于200的赋值255，小于200的赋值0
     threshold(green,green,,,THRESH_BINARY);
     threshold(red,red,,,THRESH_BINARY);

     merge(channels,dst);//通道合并

     imshow("原图",img);
     imshow("blue",blue);
     imshow("green",green);
     imshow("red",red);
     imshow("dst",dst);
     waitKey();
 }