（23）霍夫圆

知识点看这个博客：

https://blog.csdn.net/qq_41167777/article/details/84940109

===========================

 1 #include <opencv2/opencv.hpp>
 2 #include <iostream>
 3 using namespace std;
 4 using namespace cv;
 5 
 6 Mat src, dst, gray_src;
 7 const char* input_win = "input";
 8 const char* out_put = "hough-line-detection";
 9 
10 int main(int agrc, char** agrv) {
11 
12     src = imread("C:\Users\32829\Desktop\aa.jpg");
13     if (!src.data) {
14         printf("no load..
");
15         return -1;
16     }
17     namedWindow(input_win, CV_WINDOW_AUTOSIZE);
18     namedWindow(out_put, CV_WINDOW_AUTOSIZE);
19     imshow(input_win, src);
20 
21     Mat moutput;
22     medianBlur(src, moutput, 3);
23     cvtColor(moutput, moutput, CV_BGR2GRAY);
24 
25     //霍夫圆检测
26     vector<Vec3f> pcircles;
27     HoughCircles(moutput, pcircles, CV_HOUGH_GRADIENT, 1, 10, 100, 30, 5, 100);
28     src.copyTo(dst);
29     for (size_t i = 0; i < pcircles.size(); i++) {
30         Vec3f cc = pcircles[i];
31         circle(dst, Point(cc[0], cc[1]), cc[2], Scalar(0, 255, 255), 2, LINE_AA);
32         circle(dst, Point(cc[0], cc[1]), 2, Scalar(98, 23, 255), 2, LINE_AA);
33     }
34     imshow(out_put, dst);
35     waitKey(0);
36     return 0;
37 }

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