OpenCV && C++ 07 - Histogram Equalization of a Color image with OpenCV

Code

/*
作者：郑大峰
时间：2019年09月20日
环境：OpenCV 4.1.1 + VS2017
内容：Histogram Equalization of a Color image with OpenCV
*/

#include "pch.h"
#include <iostream>
#include <opencv2/opencv.hpp>

using namespace std;
using namespace cv;

int main()
{
    Mat image = imread("claudia.png");

    if (image.empty())
    {
        cout << "Could not open or find the image" << endl;
        cin.get();
        return -1;
    }

    //Convert the image from BGR to YCrCb color space
    Mat hist_equalized_image;
    cvtColor(image, hist_equalized_image, COLOR_BGR2YCrCb);

    //Split the image into 3 channels; Y, Cr and Cb channels respectively and store it in a std::vector
    vector<Mat> vec_channels;
    split(hist_equalized_image, vec_channels);

    //Equalize the histogram of only the Y channel
    equalizeHist(vec_channels[0], vec_channels[0]);

    //Merge 3 channels in the vector to form the color image in YCrCB color space.
    merge(vec_channels, hist_equalized_image);

    //Convert the histogram equalized image from YCrCb to BGR color space again
    cvtColor(hist_equalized_image, hist_equalized_image, COLOR_YCrCb2BGR);

    //Define the names of windows
    String windowNameOfOriginalImage = "Original Image";
    String windowNameOfHistogramEqualized = "Histogram Equalized Color Image";

    // Create windows with the above names
    namedWindow(windowNameOfOriginalImage, WINDOW_NORMAL);
    namedWindow(windowNameOfHistogramEqualized, WINDOW_NORMAL);

    // Show images inside the created windows.
    imshow(windowNameOfOriginalImage, image);
    imshow(windowNameOfHistogramEqualized, hist_equalized_image);

    waitKey(0); // Wait for any key stroke

    destroyAllWindows(); //destroy all open windows

    return 0;
}

Result