ORBSLAM3跑tum数据集的轨迹与真实轨迹对齐并输出对齐后轨迹文件C++代码

以下是使用 ORBSLAM3 跑 TUM 数据集并输出对齐后轨迹文件的 C++ 代码示例：

#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <iomanip>

#include <opencv2/core/core.hpp>

#include "System.h"

using namespace std;

int main(int argc, char **argv)
{
    if(argc != 4)
    {
        cerr << endl << "Usage: ./mono_tum path_to_vocabulary path_to_settings path_to_dataset" << endl;
        return 1;
    }

    ORB_SLAM3::System SLAM(argv[1],argv[2],ORB_SLAM3::System::MONOCULAR,true);

    ifstream fGroundTruth;
    fGroundTruth.open(argv[3] + string("/groundtruth.txt"));
    if(!fGroundTruth.is_open())
    {
        cerr << endl << "Failed to open file: " << argv[3] + string("/groundtruth.txt") << endl;
        return 1;
    }

    ofstream fTrajectory;
    fTrajectory.open("trajectory.txt");
    if(!fTrajectory.is_open())
    {
        cerr << endl << "Failed to open file: trajectory.txt" << endl;
        return 1;
    }

    string sLine;
    int nLineNum = 0;
    while(getline(fGroundTruth,sLine))
    {
        if(sLine.empty() || sLine[0] == '#')
            continue;

        nLineNum++;

        double t;
        float tx, ty, tz, qx, qy, qz, qw;
        stringstream ss;
        ss << sLine;
        ss >> t >> tx >> ty >> tz >> qx >> qy >> qz >> qw;

        cv::Mat Tcw = SLAM.TrackMonocular(cv::Mat(),cv::Mat(),t);

        if(!Tcw.empty())
        {
            cv::Mat Rwc = Tcw.rowRange(0,3).colRange(0,3).t();
            cv::Mat twc = -Rwc*Tcw.rowRange(0,3).col(3);

            float x = twc.at<float>(0);
            float y = twc.at<float>(1);
            float z = twc.at<float>(2);

            float roll, pitch, yaw;
            ORB_SLAM3::Converter::QuaternionToEuler(qw,qx,qy,qz,roll,pitch,yaw);

            float scale = 1.0f;
            if(nLineNum > 1)
            {
                getline(fGroundTruth,sLine);
                double tPrev;
                float txPrev, tyPrev, tzPrev, qxPrev, qyPrev, qzPrev, qwPrev;
                stringstream ssPrev;
                ssPrev << sLine;
                ssPrev >> tPrev >> txPrev >> tyPrev >> tzPrev >> qxPrev >> qyPrev >> qzPrev >> qwPrev;

                cv::Mat Twc = cv::Mat::eye(4,4,CV_32F);
                ORB_SLAM3::Converter::QuaternionToMat(qxPrev,qyPrev,qzPrev,qwPrev,Twc.rowRange(0,3).colRange(0,3));
                Twc.at<float>(0,3) = txPrev;
                Twc.at<float>(1,3) = tyPrev;
                Twc.at<float>(2,3) = tzPrev;

                cv::Mat Ow = Twc.rowRange(0,3).col(3);
                cv::Mat OwPrev = cv::Mat(3,1,CV_32F);
                OwPrev.at<float>(0) = txPrev;
                OwPrev.at<float>(1) = tyPrev;
                OwPrev.at<float>(2) = tzPrev;

                cv::Mat v = Ow - OwPrev;
                scale = cv::norm(v);
            }

            fTrajectory << fixed << setprecision(6) << t << " "
                        << x << " " << y << " " << z << " "
                        << roll << " " << pitch << " " << yaw << " "
                        << scale << endl;
        }
    }

    fGroundTruth.close();
    fTrajectory.close();

    SLAM.Shutdown();

    return 0;
}

注意事项：

1. 代码中的 `path_to_vocabulary` 和 `path_to_settings` 分别表示 ORB_SLAM3 的词汇文件和配置文件路径，需要根据实际情况进行修改。
2. 代码中的 `path_to_dataset` 表示 TUM 数据集所在的文件夹路径，需要根据实际情况进行修改。
3. 输出的对齐轨迹文件为 `trajectory.txt`，每行数据包括时间戳、位置坐标、欧拉角和尺度因子，用空格分隔。
4. 代码中使用了 Ground Truth 数据进行轨迹对齐，需要保证 TUM 数据集中的 `groundtruth.txt` 文件是存在并且格式正确的。如果没有 Ground Truth 数据，可以使用其它方法进行轨迹对齐。

希望对你有帮助！