1、参考博客：https://www.cnblogs.com/riddick/p/7989871.html

2、但是博客代码的i和j的下标表示有些问题

3、修改code-1之后，可以成功运行的代码

1 #include 
     
        2 #include 
      
         3 #include 
       
          4   5 using namespace cv;  6 using namespace std;  7   8 //计算亮度中值和灰度<=中值的像素点个数  9 int calMediaValue(const int histogram[], int thresh) 10 { 11     int sum = 0; 12     for (int i = 0; i < 256; ++i) 13     { 14         sum += histogram[i]; 15         if (sum >= thresh) 16         { 17             return i; 18         } 19     } 20     return 255; 21 } 22  23 void fastMedianBlur(const Mat &srcImg, Mat &dstImg, int diameter) 24 { 25     int radius = (diameter - 1) / 2; 26     int imgW = srcImg.cols;   // 1920    宽 27     int imgH = srcImg.rows;   // 1200    高 28     int channels = srcImg.channels();  // 1 29     dstImg = Mat::zeros(imgH, imgW, CV_8UC1); 30     int windowSize = diameter*diameter;  // 25 31  32     //直方图 33     int Hist[256] = { 0 }; 34     int histogramSize = 256;//灰度等级 35     int thresholdValue = windowSize / 2 + 1;   // 13 36  37     uchar *pSrcData = srcImg.data; 38     uchar *pDstData = dstImg.data; 39  40     int right = imgW - radius;   // 1918 41     int bot = imgH - radius;     // 1198 42     for (int j = radius; j < bot; j++)   // 行   43     { 44          45         for (int i = radius; i < right; i++)   //列 46         { 47             //每一行第一个待滤波像素建立直方图 48             if (i == radius) 49             { 50                 memset(Hist, 0, histogramSize*sizeof(int)); 51                 for (int y = j - radius; y <= min(j + radius, imgH); y++) 52                 { 53                     for (int x = i - radius; x <= min(i + radius,imgW); x++) 54                     { 55                         uchar value = pSrcData[y*imgW + x]; 56                         Hist[value]++; 57                     } 58                 } 59             } 60             else//更新直方图 61             { 62                 int left = i - radius - 1; 63                 int right = i + radius; 64                 for (int y = j - radius; y <= min(j + radius, imgH); y++) 65                 { 66                     //减去左边一列 67                     int leftIdx = y*imgW + left; 68                     uchar leftValue = pSrcData[leftIdx]; 69                     Hist[leftValue]--; 70  71                     //加上右边一列 72                     int rightIdx = y*imgW + right; 73                     uchar rightValue = pSrcData[rightIdx]; 74                     Hist[rightValue]++; 75                 } 76             } 77  78             //直方图求中值 79             uchar filterValue = calMediaValue(Hist, thresholdValue); 80             pDstData[j*imgW + i] = filterValue; 81         } 82     } 83  84     //边界直接赋原始值，不做滤波处理 85     pSrcData = srcImg.data; 86     pDstData = dstImg.data; 87     //上下边界 88     for (int i = 0; i < imgW; i++) 89     { 90         for (int j = 0; j < radius; j++) 91         { 92             int idxTop = j*imgW + i; 93             pDstData[idxTop] = pSrcData[idxTop]; 94             int idxBot = (imgH - j - 1)*imgW + i; 95             pDstData[idxBot] = pSrcData[idxBot]; 96         } 97     } 98     //左右边界 99     for (int j = radius; j < imgH - radius - 1; j++)100     {101         for (int i = 0; i < radius; i++)102         {103             int idxLeft = j*imgW + i;104             pDstData[idxLeft] = pSrcData[idxLeft];105             int idxRight = j*imgW + imgW - i - 1;106             pDstData[idxRight] = pSrcData[idxRight];107         }108     }109 }110 111 112 int main()113 {114     string imgPath = "D:\\Images\\漂亮的图片\\";115     Mat srcImg = imread(imgPath + "2.jpg", 0);116     Mat dstImg;117 118     double t0 = cv::getTickCount();119     fastMedianBlur(srcImg, dstImg, 5);120     double t1 = cv::getTickCount();121 122     cout << "time=" << (t1 - t0) / cv::getTickFrequency() << "  seconds" << endl;123 124     imwrite("srcImg.jpg", srcImg);125     imwrite("myFilter.jpg", dstImg);126 127     return 0;128 }
       
      
     

结果示例，中值滤波后的图片