C++之OpenCV图像高光调整具体流程

#include <iostream>

#include <opencv2/opencv.hpp>

  

using namespace std;

using namespace cv;

  

cv::Mat HighLight(cv::Mat input, int light);

  

int main()

{

    cv::Mat src = imread("test3.jpg");

    int light1 = 50;

    int light2 = -50;

    cv::Mat result1 = HighLight(src, light1);

    cv::Mat result2 = HighLight(src, light2);

    imshow("original", src);

    imshow("result1", result1);

    imshow("result2", result2);

    waitKey(0);

    return 0;

}

  

// 图像高光选取

cv::Mat HighLight(cv::Mat input, int light)

{

    // 生成灰度图

    cv::Mat gray = cv::Mat::zeros(input.size(), CV_32FC1);

    cv::Mat f = input.clone();

    f.convertTo(f, CV_32FC3);

    vector<cv::Mat> pics;

    split(f, pics);

    gray = 0.299f*pics[2] + 0.587*pics[2] + 0.114*pics[0];

    gray = gray / 255.f;

  

    // 确定高光区

    cv::Mat thresh = cv::Mat::zeros(gray.size(), gray.type());

    thresh = gray.mul(gray);

    // 取平均值作为阈值

    Scalar t = mean(thresh);

    cv::Mat mask = cv::Mat::zeros(gray.size(), CV_8UC1);

    mask.setTo(255, thresh >= t[0]);

  

    // 参数设置

    int max = 4;

    float bright = light / 100.0f / max;

    float mid = 1.0f + max * bright;

  

    // 边缘平滑过渡

    cv::Mat midrate = cv::Mat::zeros(input.size(), CV_32FC1);

    cv::Mat brightrate = cv::Mat::zeros(input.size(), CV_32FC1);

    for (int i = 0; i < input.rows; ++i)

    {

        uchar *m = mask.ptr<uchar>(i);

        float *th = thresh.ptr<float>(i);

        float *mi = midrate.ptr<float>(i);

        float *br = brightrate.ptr<float>(i);

        for (int j = 0; j < input.cols; ++j)

        {

            if (m[j] == 255)

            {

                mi[j] = mid;

                br[j] = bright;

            }

            else {

                mi[j] = (mid - 1.0f) / t[0] * th[j] + 1.0f;

                br[j] = (1.0f / t[0] * th[j])*bright;

            }

        }

    }

  

    // 高光提亮，获取结果图

    cv::Mat result = cv::Mat::zeros(input.size(), input.type());

    for (int i = 0; i < input.rows; ++i)

    {

        float *mi = midrate.ptr<float>(i);

        float *br = brightrate.ptr<float>(i);

        uchar *in = input.ptr<uchar>(i);

        uchar *r = result.ptr<uchar>(i);

        for (int j = 0; j < input.cols; ++j)

        {

            for (int k = 0; k < 3; ++k)

            {

                float temp = pow(float(in[3 * j + k]) / 255.f, 1.0f / mi[j])*(1.0 / (1 - br[j]));

                if (temp > 1.0f)

                    temp = 1.0f;

                if (temp < 0.0f)

                    temp = 0.0f;

                uchar utemp = uchar(255*temp);

                r[3 * j + k] = utemp;

            }

  

        }

    }

    return result;

}