请用C++版的opencv写一段代码，要求用摄像头识别红蓝色的圆环，并且绘制出准确的圆环轮廓和对应的圆心，可以用键盘按键q切换红蓝模式

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

using namespace cv;
using namespace std;

int main()
{
    VideoCapture capture(0);
    if (!capture.isOpened())
    {
        cout << "摄像头打开失败！" << endl;
        return -1;
    }

    Mat frame, hsv, mask_red, mask_blue;
    while (1)
    {
        capture.read(frame);
        if (frame.empty())
        {
            cout << "读取视频失败！" << endl;
            break;
        }

        // 将图像转换到HSV色彩空间
        cvtColor(frame, hsv, COLOR_BGR2HSV);

        // 红色圆环的颜色范围
        Scalar lower_red(0, 70, 50);
        Scalar upper_red(10, 255, 255);
        inRange(hsv, lower_red, upper_red, mask_red);

        // 蓝色圆环的颜色范围
        Scalar lower_blue(100, 70, 50);
        Scalar upper_blue(124, 255, 255);
        inRange(hsv, lower_blue, upper_blue, mask_blue);

        // 切换红蓝模式
        char key = waitKey(1);
        if (key == 'q' || key == 'Q')
        {
            destroyAllWindows();
            break;
        }
        else if (key == 'r' || key == 'R')
        {
            imshow("Camera", mask_red);
            continue;
        }
        else if (key == 'b' || key == 'B')
        {
            imshow("Camera", mask_blue);
            continue;
        }

        // 对图像进行形态学操作，去除噪声
        Mat kernel = getStructuringElement(MORPH_RECT, Size(5, 5));
        morphologyEx(mask_red, mask_red, MORPH_OPEN, kernel);
        morphologyEx(mask_blue, mask_blue, MORPH_OPEN, kernel);

        // 查找圆形轮廓
        vector<vector<Point>> contours_red, contours_blue;
        vector<Vec4i> hierarchy_red, hierarchy_blue;
        findContours(mask_red, contours_red, hierarchy_red, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE);
        findContours(mask_blue, contours_blue, hierarchy_blue, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE);

        // 绘制圆形轮廓和圆心
        for (size_t i = 0; i < contours_red.size(); i++)
        {
            double area = contourArea(contours_red[i]);
            if (area < 100)
                continue;

            RotatedRect rect = minAreaRect(contours_red[i]);
            Point2f center = rect.center;
            circle(frame, center, 4, Scalar(0, 255, 0), -1);
            ellipse(frame, rect, Scalar(0, 255, 0), 2);
        }
        for (size_t i = 0; i < contours_blue.size(); i++)
        {
            double area = contourArea(contours_blue[i]);
            if (area < 100)
                continue;

            RotatedRect rect = minAreaRect(contours_blue[i]);
            Point2f center = rect.center;
            circle(frame, center, 4, Scalar(255, 0, 0), -1);
            ellipse(frame, rect, Scalar(255, 0, 0), 2);
        }

        imshow("Camera", frame);
    }

    capture.release();
    return 0;
}