opencv寻找多边形拐点 c++代码

以下是使用OpenCV查找多边形拐点的C ++代码示例：

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;

int main()
{
    Mat image = imread("poly.png", IMREAD_GRAYSCALE);
    if (image.empty())
    {
        cout << "Could not read the image" << endl;
        return -1;
    }

    threshold(image, image, 128, 255, THRESH_BINARY);
    vector<vector<Point>> contours;
    findContours(image, contours, RETR_LIST, CHAIN_APPROX_SIMPLE);

    for (size_t i = 0; i < contours.size(); i++)
    {
        vector<Point> polygon = contours[i];
        vector<Point> corners;
        for (size_t j = 0; j < polygon.size(); j++)
        {
            Point prev = polygon[(j + polygon.size() - 1) % polygon.size()];
            Point cur = polygon[j];
            Point next = polygon[(j + 1) % polygon.size()];

            double angle = acos((prev - cur).dot(next - cur) / (norm(prev - cur) * norm(next - cur)));
            if (angle < CV_PI * 0.9)
            {
                corners.push_back(cur);
            }
        }

        cout << "Polygon " << i << " has " << corners.size() << " corners" << endl;
        for (size_t j = 0; j < corners.size(); j++)
        {
            circle(image, corners[j], 5, Scalar(255), 2);
        }
    }

    imshow("Contours", image);
    waitKey(0);
    return 0;
}

在这个示例中，我们首先从文件中读取灰度图像。然后使用二值化阈值将图像转换为黑白。接下来，我们使用`findContours`函数查找多边形的轮廓。对于每个多边形，我们使用角度检测方法查找拐点。如果两条相邻的边的夹角小于90度，则它们之间的顶点被视为拐点。最后，我们在图像中绘制每个多边形的拐点，并在控制台上打印拐点数。