opencvc++进行四个摄像头标定，分别得到并保存每个相机的的内参，外参，以及畸变系数的C++代码

以下是使用OpenCV C++进行四个摄像头标定的代码示例：

#include <opencv2/opencv.hpp>
#include <opencv2/calib3d.hpp>
#include <iostream>
#include <vector>

using namespace std;
using namespace cv;

const int chess_rows = 9; // 棋盘格行数
const int chess_cols = 6; // 棋盘格列数

int main(int argc, char** argv) {
    vector<vector<Point3f>> object_points; // 棋盘格上的三维点
    vector<vector<Point2f>> image_points; // 棋盘格上的二维点
    vector<Mat> rvecs, tvecs; // 旋转向量和平移向量
    vector<float> reproj_errs; // 重投影误差
    vector<Point2f> corners; // 棋盘格角点
    Size img_size; // 图像尺寸

    // 读取图像并查找棋盘格角点
    for (int i = 0; i < 4; i++) {
        // 读取图像
        Mat img = imread("img" + to_string(i) + ".jpg");
        if (img.empty()) {
            cout << "Failed to read image " << i << endl;
            return -1;
        }

        // 查找棋盘格角点
        bool found = findChessboardCorners(img, Size(chess_cols, chess_rows), corners);
        if (!found) {
            cout << "Failed to find corners in image " << i << endl;
            return -1;
        }

        // 亚像素精确化
        cvtColor(img, img, COLOR_BGR2GRAY);
        cornerSubPix(img, corners, Size(11, 11), Size(-1, -1), TermCriteria(TermCriteria::EPS + TermCriteria::COUNT, 30, 0.1));

        // 显示角点
        drawChessboardCorners(img, Size(chess_cols, chess_rows), corners, found);
        imshow("corners" + to_string(i), img);
        waitKey(0);

        // 存储角点
        img_size = img.size();
        vector<Point3f> obj(chess_rows * chess_cols);
        for (int r = 0; r < chess_rows; r++) {
            for (int c = 0; c < chess_cols; c++) {
                obj[r * chess_cols + c] = Point3f(c * 25.0f, r * 25.0f, 0.0f);
            }
        }
        object_points.push_back(obj);
        image_points.push_back(corners);
    }

    // 标定相机
    Mat camera_matrix = Mat::eye(3, 3, CV_64F);
    Mat dist_coeffs = Mat::zeros(5, 1, CV_64F);
    vector<vector<Point3f>> object_points_vec(4, object_points);
    vector<vector<Point2f>> image_points_vec(4, image_points);
    double rms = calibrateCameraRO(object_points_vec, image_points_vec, img_size, 0, camera_matrix, dist_coeffs, rvecs, tvecs);

    // 输出标定结果
    cout << "Camera matrix:" << endl;
    cout << camera_matrix << endl;
    cout << "Distortion coefficients:" << endl;
    cout << dist_coeffs << endl;
    for (int i = 0; i < 4; i++) {
        cout << "Rotation vector for camera " << i << ":" << endl;
        cout << rvecs[i] << endl;
        cout << "Translation vector for camera " << i << ":" << endl;
        cout << tvecs[i] << endl;
    }

    // 保存标定结果
    FileStorage fs("calibration.xml", FileStorage::WRITE);
    fs << "camera_matrix" << camera_matrix;
    fs << "dist_coeffs" << dist_coeffs;
    for (int i = 0; i < 4; i++) {
        fs << "rvecs" + to_string(i) << rvecs[i];
        fs << "tvecs" + to_string(i) << tvecs[i];
    }
    fs.release();

    return 0;
}

说明：

1. 使用`findChessboardCorners()`函数查找棋盘格角点，并使用`cornerSubPix()`函数对角点进行亚像素精确化；
2. 使用`calibrateCameraRO()`函数对相机进行标定，并输出标定结果；
3. 使用`FileStorage`类保存标定结果到XML文件中。

注意：

1. 在实际使用中，需要根据自己的相机和棋盘格大小修改代码中的参数；
2. 代码中使用了四个相机，如果只有一个相机，可以将循环体中的代码删除，并将`object_points`和`image_points`变量改为单个变量即可。