C++ opencv直线检测

OpenCV 中提供了 Hough 变换来进行直线检测。下面是一个简单的示例代码：

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

using namespace cv;
using namespace std;

int main()
{
    Mat src = imread("test.jpg");
    if (src.empty())
    {
        cout << "Failed to read image" << endl;
        return -1;
    }

    Mat gray, edges;
    cvtColor(src, gray, COLOR_BGR2GRAY);
    Canny(gray, edges, 50, 200, 3);

    vector<Vec2f> lines;
    HoughLines(edges, lines, 1, CV_PI / 180, 150, 0, 0);

    for (size_t i = 0; i < lines.size(); i++)
    {
        float rho = lines[i][0], theta = lines[i][1];
        Point pt1, pt2;
        double a = cos(theta), b = sin(theta);
        double x0 = a * rho, y0 = b * rho;
        pt1.x = cvRound(x0 + 1000 * (-b));
        pt1.y = cvRound(y0 + 1000 * (a));
        pt2.x = cvRound(x0 - 1000 * (-b));
        pt2.y = cvRound(y0 - 1000 * (a));
        line(src, pt1, pt2, Scalar(0, 0, 255), 2, LINE_AA);
    }

    imshow("Result", src);
    waitKey(0);

    return 0;
}

该示例代码从文件中读取一张图像，然后将其转换为灰度图像和边缘图像。接着，使用 Hough 变换检测直线，并在原始图像上绘制检测到的直线。最后将结果显示出来。