主要是利用霍夫圆检测、面积筛选等完成多个圆形检测，具体代码及结果如下。
第一部分是头文件（common.h）：
#pragma once
#include<opencv2/opencv.hpp>
#include<opencv2/highgui.hpp>
#include<iostream>
using namespace std;
using namespace cv;
extern Mat src;
void imageBasicInformation(Mat& src);//图像基本信息
const Mat houghCirclePre(Mat& srcPre);//霍夫圆检测预处理
void houghCircle(Mat& srcPreHough);//霍夫圆检测
const Mat RectCirclePre(Mat& srcPre);//面积筛选拟合圆的预处理
void AreaCircles(Mat& AreaInput);//面积筛选拟合圆检测
第二部分是主函数：
#include"common.h"
Mat src;
int main()
{
src = imread("1.webp",1);
if (src.empty())
{
cout << "图像不存在！" << endl;
}
else
{
namedWindow("原图", 1);
imshow("原图", src);
imageBasicInformation(src);
Mat srcPreHough = houghCirclePre(src);
houghCircle(srcPreHough);
Mat RectCir = RectCirclePre(src);
AreaCircles(RectCir);
waitKey(0);
destroyAllWindows();
}
return 0；
}
第三部分为霍夫圆检测函数（hough.cpp）
主要包括输出图像的基本信息函数：void imageBasicInformation(Mat& src)
霍夫圆检测预处理函数：const Mat houghCirclePre(Mat& srcPre)
霍夫圆检测函数：void houghCircle(Mat& srcPreHough)
#include"common.h"
Mat graySrc, srcPre;//灰度图，霍夫检测预处理，
Mat threshold_grayaSrc;//二值化图
Mat erode_threshold_graySrc, dilate_threshold_graySrc;//二值化后腐蚀，二值化后膨胀
void imageBasicInformation(Mat& src)
{
int cols = src.cols;
int rows = src.rows;
int channels = src.channels();
cout << "图像宽为：" << cols << endl;
cout << "图像高为：" << rows << endl;
cout << "图像通道数：" << channels << endl;
}
const Mat houghCirclePre(Mat& srcPre)
{
double houghCirclePreTime = static_cast<double>(getTickCount());
cvtColor(srcPre, graySrc, COLOR_BGR2GRAY);
GaussianBlur(graySrc, graySrc, Size(3, 3), 2, 2);//滤波
threshold(graySrc, threshold_grayaSrc, 150, 255, 1);//二值化
Mat element = getStructuringElement(MORPH_RECT, Size(15, 15));
dilate(threshold_grayaSrc, dilate_threshold_graySrc, element);//膨胀
erode(dilate_threshold_graySrc, erode_threshold_graySrc, element);//腐蚀
houghCirclePreTime = ((double)getTickCount() - houghCirclePreTime) / getTickFrequency();
cout << "霍夫圆预处理时间为：" << houghCirclePreTime << "秒" << endl;
return erode_threshold_graySrc;
}
void houghCircle(Mat& srcPreHough)
{
cout << "进入霍夫圆检测" << endl;
vector<Vec3f> circles;
HoughCircles(srcPreHough, circles, HOUGH_GRADIENT, 1, 60, 1, 35, 0, 0);
cout << "圆的个数" << circles.size() << endl;
for (size_t i = 0;i < circles.size();i++)
{
Point center(cvRound(circles[i][0]), cvRound(circles[i][1]));
int radius = cvRound(circles[i][2]);
circle(src, center, 3, Scalar(0, 255, 0), -1, 8, 0);//画圆心
circle(src, center, radius, Scalar(0, 0, 255), 3, 8, 0);//画圆
}
namedWindow("霍夫检测结果", 0);
imshow("霍夫检测结果", src);
imwrite("霍夫圆检测结果.webp", src);//保存检测结果
}
第四部分为利用面积筛选拟合圆检测（AreaCircle.cpp）
主要包括预处理函数：const Mat RectCirclePre(Mat& srcPre)
面积筛选拟合圆检测函数：void AreaCircles(Mat& AreaInput)
#include"common.h"
Mat graySrcArea, thresholdGraySrc;//灰度图像，二值化图像
Mat dilateThresholdGraySrc, erodeThresholdGraySrc;//二值化后膨胀图像，膨胀之后的腐蚀图像
const Mat RectCirclePre(Mat& srcPre)
{
cvtColor(srcPre, graySrcArea, COLOR_BGR2GRAY);
GaussianBlur(graySrcArea, graySrcArea, Size(3, 3), 2, 2);
threshold(graySrcArea, thresholdGraySrc, 100, 255, 1);//二值化，阈值要根据自己的图像自己调整
Mat element = getStructuringElement(MORPH_RECT, Size(15, 15));
dilate(thresholdGraySrc, dilateThresholdGraySrc, element);//膨胀
erode(dilateThresholdGraySrc, erodeThresholdGraySrc, element);//腐蚀
return erodeThresholdGraySrc;
}
void AreaCircles(Mat& AreaInput)
{
vector<vector<Point>> RectContours;
vector<Vec4i> Hierarchy;
findContours(AreaInput, RectContours, Hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0));
Mat drawing = Mat::zeros(src.size(), CV_8UC3);
for (int i = 0;i < RectContours.size();i++)
{
double area = contourArea(RectContours[i]);
cout << area << endl;//输出所有计算出来的面积，方便下一步设置阈值
if (area > 15000 && area < 100000)//根据上一步计算的阈值设置范围
{
drawContours(drawing, RectContours, i, Scalar(0, 255, 0), 2,8, Hierarchy, 0, Point());
RotatedRect Rect = fitEllipse(RectContours[i]);
circle(src, Rect.center, 2, Scalar(0, 255, 0), 2, 8, 0);//在原图画出圆心
ellipse(src, Rect, Scalar(0, 0, 255), 2);//在原图画出轮廓
}
}
namedWindow("面积筛选拟合圆", 0);
imshow("面积筛选拟合圆", src);
imwrite("面积筛选拟合圆.webp", src);//保存检测结果
}
结果如下（自己画的两个圆）：
原图：
以下为霍夫圆检测结果：
以下为面积筛选拟合圆结果：
到此这篇关于C++利用Opencv实现多个圆形检测的文章就介绍到这了,更多相关C++ Opencv圆形检测内容请搜索易知道(ezd.cc)以前的文章或继续浏览下面的相关文章希望大家以后多多支持易知道(ezd.cc)！
