ORBSLAM3跑tum数据集的轨迹与真实轨迹对齐并输出轨迹文件C++代码

以下是ORBSLAM3跑TUM数据集时对齐轨迹并输出轨迹文件的C++代码：

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

#include "ORBSLAM3/System.h"
#include "ORBSLAM3/Map.h"
#include "ORBSLAM3/MapPoint.h"
#include "ORBSLAM3/KeyFrame.h"
#include "ORBSLAM3/Converter.h"

using namespace std;

int main(int argc, char** argv)
{
    if(argc != 3)
    {
        cerr << "Usage: ./run_tum path_to_vocabulary path_to_settings" << endl;
        return 1;
    }

    ORBSLAM3::System* pSLAM = new ORBSLAM3::System(argv[1], argv[2], ORBSLAM3::System::MONOCULAR, true);

    ifstream fGroundTruth("groundtruth.txt");
    if(!fGroundTruth.is_open())
    {
        cerr << "Failed to open groundtruth.txt" << endl;
        return -1;
    }

    vector<double> groundTruthTimestamps;
    vector<Eigen::Matrix4d> groundTruthPoses;

    string line;
    while(getline(fGroundTruth, line))
    {
        stringstream ss(line);
        double timestamp;
        Eigen::Matrix4d pose = Eigen::Matrix4d::Identity();
        for(int i=0; i<12; i++)
        {
            ss >> pose(i/4, i%4);
        }
        ss >> timestamp;

        groundTruthTimestamps.push_back(timestamp);
        groundTruthPoses.push_back(pose);
    }

    fGroundTruth.close();

    // Run the SLAM system on each frame
    ifstream fAssociation("associate.txt");
    if(!fAssociation.is_open())
    {
        cerr << "Failed to open associate.txt" << endl;
        return -1;
    }

    ofstream fTrajectory("trajectory.txt");
    if(!fTrajectory.is_open())
    {
        cerr << "Failed to open trajectory.txt" << endl;
        return -1;
    }
    fTrajectory << fixed << setprecision(6);

    string leftImgFile, rightImgFile, lineGT;
    while(getline(fAssociation, line))
    {
        stringstream ss(line);
        ss >> groundTruthTimestamps[0] >> leftImgFile >> groundTruthTimestamps[1] >> rightImgFile;

        cv::Mat leftImg = cv::imread(leftImgFile, CV_LOAD_IMAGE_GRAYSCALE);
        double timestamp = groundTruthTimestamps[0];

        // Pass the image to ORBSLAM3 for tracking
        pSLAM->TrackMonocular(leftImg, timestamp);

        // Get the current pose estimation from ORBSLAM3
        Eigen::Matrix4d poseEstimate = pSLAM->GetCurrentPose();

        // Find the corresponding ground truth pose
        Eigen::Matrix4d groundTruthPose;
        for(int i=0; i<groundTruthTimestamps.size(); i++)
        {
            if(abs(groundTruthTimestamps[i] - timestamp) < 0.001)
            {
                groundTruthPose = groundTruthPoses[i];
                break;
            }
        }

        // Align the ORBSLAM3 pose estimate to the ground truth pose
        Eigen::Matrix4d alignedPoseEstimate = groundTruthPose.inverse() * poseEstimate;

        // Write the aligned pose estimate to the output file
        Eigen::Quaterniond q(alignedPoseEstimate.block<3,3>(0,0));
        Eigen::Vector3d t(alignedPoseEstimate.block<3,1>(0,3));

        fTrajectory << timestamp << " " << t.x() << " " << t.y() << " " << t.z() << " " << q.x() << " " << q.y() << " " << q.z() << " " << q.w() << endl;
    }

    fAssociation.close();
    fTrajectory.close();

    delete pSLAM;
    return 0;
}

这个代码的作用是读取TUM数据集的ground truth轨迹和图像，然后使用ORBSLAM3对每一帧图像进行跟踪，并将ORBSLAM3的位姿估计与ground truth对齐，最后输出对齐后的轨迹文件trajectory.txt。你需要将路径path_to_vocabulary和path_to_settings替换为你的ORB-SLAM3词汇文件和设置文件的路径，并将图像和ground truth轨迹文件的路径设置为正确的路径。