When using a undistored image as input image

[yeoeun98]

Hello.

I'm testing mono orb slam2 using KITTI dataset.

I know that the images in the kitti dataset are undistorted images.

undistorted features are undistored again in the Frame() function.
but, Performance is good when using the kitti dataset

Is it correct not to use Frame() function???

Frame::Frame(const cv::Mat &imLeft, const cv::Mat &imRight, const double &timeStamp, ORBextractor* extractorLeft, ORBextractor* extractorRight, ORBVocabulary* voc, cv::Mat &K, cv::Mat &distCoef, const float &bf, const float &thDepth)
    :mpORBvocabulary(voc),mpORBextractorLeft(extractorLeft),mpORBextractorRight(extractorRight), mTimeStamp(timeStamp), mK(K.clone()),mDistCoef(distCoef.clone()), mbf(bf), mThDepth(thDepth),
     mpReferenceKF(static_cast<KeyFrame*>(NULL))
{
    // Frame ID
    mnId=nNextId++;

    // Scale Level Info
    mnScaleLevels = mpORBextractorLeft->GetLevels();
    mfScaleFactor = mpORBextractorLeft->GetScaleFactor();
    mfLogScaleFactor = log(mfScaleFactor);
    mvScaleFactors = mpORBextractorLeft->GetScaleFactors();
    mvInvScaleFactors = mpORBextractorLeft->GetInverseScaleFactors();
    mvLevelSigma2 = mpORBextractorLeft->GetScaleSigmaSquares();
    mvInvLevelSigma2 = mpORBextractorLeft->GetInverseScaleSigmaSquares();

    // ORB extraction
    thread threadLeft(&Frame::ExtractORB,this,0,imLeft);
    thread threadRight(&Frame::ExtractORB,this,1,imRight);
    threadLeft.join();
    threadRight.join();

    N = mvKeys.size();

    if(mvKeys.empty())
        return;

    UndistortKeyPoints();