CObservation3DRangeScan.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2020, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */

#include "obs-precomp.h"  // Precompiled headers

#include <mrpt/3rdparty/do_opencv_includes.h>
#include <mrpt/config/CConfigFileMemory.h>
#include <mrpt/core/bits_mem.h>  // vector_strong_clear
#include <mrpt/io/CFileGZInputStream.h>
#include <mrpt/io/CFileGZOutputStream.h>
#include <mrpt/math/CLevenbergMarquardt.h>
#include <mrpt/math/CMatrixF.h>
#include <mrpt/math/ops_containers.h>  // norm(), etc.
#include <mrpt/obs/CObservation3DRangeScan.h>
#include <mrpt/opengl/CPointCloud.h>
#include <mrpt/poses/CPosePDF.h>
#include <mrpt/serialization/CArchive.h>
#include <mrpt/system/CTimeLogger.h>
#include <mrpt/system/filesystem.h>
#include <mrpt/system/string_utils.h>
#include <cstring>
#include <limits>
#include <mutex>
#include <unordered_map>

using namespace std;
using namespace mrpt::obs;
using namespace mrpt::poses;
using namespace mrpt::math;
using namespace mrpt::img;
using mrpt::config::CConfigFileMemory;

// This must be added to any CSerializable class implementation file.
IMPLEMENTS_SERIALIZABLE(CObservation3DRangeScan, CObservation, mrpt::obs)

// Static LUT:

// Index info: camera parameters + range_is_depth
struct LUT_info
{
    mrpt::img::TCamera calib;
    mrpt::poses::CPose3D sensorPose;
    bool range_is_depth;
};

inline bool operator==(const LUT_info& a, const LUT_info& o)
{
    return a.calib == o.calib && a.sensorPose == o.sensorPose &&
           a.range_is_depth == o.range_is_depth;
}

namespace std
{
template <>
struct hash<LUT_info>
{
    size_t operator()(const LUT_info& k) const
    {
        size_t res = 17;
        res = res * 31 + hash<mrpt::img::TCamera>()(k.calib);
        res = res * 31 + hash<bool>()(k.range_is_depth);
        for (unsigned int i = 0; i < 6; i++)
            res = res * 31 + hash<double>()(k.sensorPose[i]);
        return res;
    }
};
}  // namespace std

static std::unordered_map<LUT_info, CObservation3DRangeScan::unproject_LUT_t>
    LUTs;
static std::mutex LUTs_mtx;

const CObservation3DRangeScan::unproject_LUT_t&
    CObservation3DRangeScan::get_unproj_lut() const
{
#if MRPT_HAS_OPENCV
    // Access to, or create upon first usage:
    LUT_info linfo;
    linfo.calib = this->cameraParams;
    linfo.sensorPose = this->sensorPose;
    linfo.range_is_depth = this->range_is_depth;

    LUTs_mtx.lock();
    // Protect against infinite memory growth: imagine sensorPose gets changed
    // every time for a sweeping sensor, etc.
    // Unlikely, but "just in case" (TM)
    if (LUTs.size() > 100) LUTs.clear();

    const unproject_LUT_t& ret = LUTs[linfo];

    LUTs_mtx.unlock();

    ASSERT_EQUAL_(rangeImage.cols(), static_cast<int>(cameraParams.ncols));
    ASSERT_EQUAL_(rangeImage.rows(), static_cast<int>(cameraParams.nrows));

    // already existed and was filled?
    unsigned int H = cameraParams.nrows, W = cameraParams.ncols;
    const size_t WH = W * H;
    if (ret.Kxs.size() == WH) return ret;

    // fill LUT upon first use:
    auto& lut = const_cast<unproject_LUT_t&>(ret);

    lut.Kxs.resize(WH);
    lut.Kys.resize(WH);
    lut.Kzs.resize(WH);
    lut.Kxs_rot.resize(WH);
    lut.Kys_rot.resize(WH);
    lut.Kzs_rot.resize(WH);

    // Undistort all points:
    cv::Mat pts(1, WH, CV_32FC2), undistort_pts(1, WH, CV_32FC2);

    const auto& intrMat = cameraParams.intrinsicParams;
    const auto& dist = cameraParams.dist;
    cv::Mat cv_distortion(
        1, dist.size(), CV_64F, const_cast<double*>(&dist[0]));
    cv::Mat cv_intrinsics(3, 3, CV_64F);
    for (int i = 0; i < 3; i++)
        for (int j = 0; j < 3; j++)
            cv_intrinsics.at<double>(i, j) = intrMat(i, j);

    for (unsigned int r = 0; r < H; r++)
        for (unsigned int c = 0; c < W; c++)
        {
            auto& p = pts.at<cv::Vec2f>(r * W + c);
            p[0] = c;
            p[1] = r;
        }

    cv::undistortPoints(pts, undistort_pts, cv_intrinsics, cv_distortion);

    // Note: undistort_pts now holds point coordinates with (-1,-1)=top left,
    // (1,1)=bottom-right

    ASSERT_EQUAL_(undistort_pts.size().area(), static_cast<int>(WH));
    undistort_pts.reshape(WH);

    float* kxs = &lut.Kxs[0];
    float* kys = &lut.Kys[0];
    float* kzs = &lut.Kzs[0];
    float* kxs_rot = &lut.Kxs_rot[0];
    float* kys_rot = &lut.Kys_rot[0];
    float* kzs_rot = &lut.Kzs_rot[0];

    for (size_t idx = 0; idx < WH; idx++)
    {
        const auto& p = undistort_pts.at<cv::Vec2f>(idx);
        const float c = p[0], r = p[1];

        // XYZ -> (-Y,-Z, X)
        auto v = mrpt::math::TPoint3Df(1.0f, -c, -r);

        // Range instead of depth? Use a unit vector:
        if (!this->range_is_depth) v *= 1.0f / v.norm();

        // compute also the rotated version:
        auto v_rot = sensorPose.rotateVector(v);

        *kxs++ = v.x;
        *kys++ = v.y;
        *kzs++ = v.z;

        *kxs_rot++ = v_rot.x;
        *kys_rot++ = v_rot.y;
        *kzs_rot++ = v_rot.z;
    }

    return ret;
#else
    THROW_EXCEPTION("This method requires MRPT built against OpenCV");
#endif
}

static bool EXTERNALS_AS_TEXT_value = false;
void CObservation3DRangeScan::EXTERNALS_AS_TEXT(bool value)
{
    EXTERNALS_AS_TEXT_value = value;
}
bool CObservation3DRangeScan::EXTERNALS_AS_TEXT()
{
    return EXTERNALS_AS_TEXT_value;
}

// Whether to use a memory pool for 3D points:
#define COBS3DRANGE_USE_MEMPOOL

// Do performance time logging?
//#define  PROJ3D_PERFLOG

// Data types for memory pooling CObservation3DRangeScan:
#ifdef COBS3DRANGE_USE_MEMPOOL

#include <mrpt/system/CGenericMemoryPool.h>

// Memory pool for XYZ points ----------------
struct CObservation3DRangeScan_Points_MemPoolParams
{
    /** Width*Height, that is, the number of 3D points */
    size_t WH{0};
    inline bool isSuitable(
        const CObservation3DRangeScan_Points_MemPoolParams& req) const
    {
        return WH >= req.WH;
    }
};
struct CObservation3DRangeScan_Points_MemPoolData
{
    std::vector<float> pts_x, pts_y, pts_z;
    /** for each point, the corresponding (x,y) pixel coordinates */
    std::vector<uint16_t> idxs_x, idxs_y;
};
using TMyPointsMemPool = mrpt::system::CGenericMemoryPool<
    CObservation3DRangeScan_Points_MemPoolParams,
    CObservation3DRangeScan_Points_MemPoolData>;

// Memory pool for the rangeImage matrix ----------------
struct CObservation3DRangeScan_Ranges_MemPoolParams
{
    /** Size of matrix */
    int H{0}, W{0};
    inline bool isSuitable(
        const CObservation3DRangeScan_Ranges_MemPoolParams& req) const
    {
        return H == req.H && W == req.W;
    }
};
struct CObservation3DRangeScan_Ranges_MemPoolData
{
    mrpt::math::CMatrix_u16 rangeImage;
};
using TMyRangesMemPool = mrpt::system::CGenericMemoryPool<
    CObservation3DRangeScan_Ranges_MemPoolParams,
    CObservation3DRangeScan_Ranges_MemPoolData>;

static void mempool_donate_xyz_buffers(CObservation3DRangeScan& obs)
{
    if (obs.points3D_x.empty()) return;
    // Before dying, donate my memory to the pool for the joy of future
    // class-brothers...
    TMyPointsMemPool* pool = TMyPointsMemPool::getInstance();
    if (!pool) return;

    CObservation3DRangeScan_Points_MemPoolParams mem_params;
    mem_params.WH = obs.points3D_x.capacity();
    if (obs.points3D_y.capacity() != mem_params.WH)
        obs.points3D_y.resize(mem_params.WH);
    if (obs.points3D_z.capacity() != mem_params.WH)
        obs.points3D_z.resize(mem_params.WH);
    if (obs.points3D_idxs_x.capacity() != mem_params.WH)
        obs.points3D_idxs_x.resize(mem_params.WH);
    if (obs.points3D_idxs_y.capacity() != mem_params.WH)
        obs.points3D_idxs_y.resize(mem_params.WH);

    auto* mem_block = new CObservation3DRangeScan_Points_MemPoolData();
    obs.points3D_x.swap(mem_block->pts_x);
    obs.points3D_y.swap(mem_block->pts_y);
    obs.points3D_z.swap(mem_block->pts_z);
    obs.points3D_idxs_x.swap(mem_block->idxs_x);
    obs.points3D_idxs_y.swap(mem_block->idxs_y);

    pool->dump_to_pool(mem_params, mem_block);
}
void mempool_donate_range_matrix(CObservation3DRangeScan& obs)
{
    if (obs.rangeImage.cols() == 0 || obs.rangeImage.rows() == 0) return;

    // Before dying, donate my memory to the pool for the joy of future
    // class-brothers...
    TMyRangesMemPool* pool = TMyRangesMemPool::getInstance();
    if (!pool) return;

    CObservation3DRangeScan_Ranges_MemPoolParams mem_params;
    mem_params.H = obs.rangeImage.rows();
    mem_params.W = obs.rangeImage.cols();

    auto* mem_block = new CObservation3DRangeScan_Ranges_MemPoolData();
    obs.rangeImage.swap(mem_block->rangeImage);

    pool->dump_to_pool(mem_params, mem_block);
}
#endif

CObservation3DRangeScan::~CObservation3DRangeScan()
{
#ifdef COBS3DRANGE_USE_MEMPOOL
    mempool_donate_xyz_buffers(*this);
    mempool_donate_range_matrix(*this);
#endif
}

uint8_t CObservation3DRangeScan::serializeGetVersion() const { return 10; }
void CObservation3DRangeScan::serializeTo(
    mrpt::serialization::CArchive& out) const
{
    // The data
    out << maxRange << sensorPose;
    out << hasPoints3D;
    if (hasPoints3D)
    {
        ASSERT_(
            points3D_x.size() == points3D_y.size() &&
            points3D_x.size() == points3D_z.size() &&
            points3D_idxs_x.size() == points3D_x.size() &&
            points3D_idxs_y.size() == points3D_x.size());
        uint32_t N = points3D_x.size();
        out << N;
        if (N)
        {
            out.WriteBufferFixEndianness(&points3D_x[0], N);
            out.WriteBufferFixEndianness(&points3D_y[0], N);
            out.WriteBufferFixEndianness(&points3D_z[0], N);
            out.WriteBufferFixEndianness(&points3D_idxs_x[0], N);  // New in v8
            out.WriteBufferFixEndianness(&points3D_idxs_y[0], N);  // New in v8
        }
    }

    out << hasRangeImage;
    out << rangeUnits;  // new in v9
    if (hasRangeImage)
    {
        out.WriteAs<uint32_t>(rangeImage.rows());
        out.WriteAs<uint32_t>(rangeImage.cols());
        if (rangeImage.size() != 0)
            out.WriteBufferFixEndianness<uint16_t>(
                rangeImage.data(), rangeImage.size());
    }
    out << hasIntensityImage;
    if (hasIntensityImage) out << intensityImage;
    out << hasConfidenceImage;
    if (hasConfidenceImage) out << confidenceImage;
    out << cameraParams;  // New in v2
    out << cameraParamsIntensity;  // New in v4
    out << relativePoseIntensityWRTDepth;  // New in v4

    out << stdError;
    out << timestamp;
    out << sensorLabel;

    // New in v3:
    out << m_points3D_external_stored << m_points3D_external_file;
    out << m_rangeImage_external_stored << m_rangeImage_external_file;

    // New in v5:
    out << range_is_depth;

    // New in v6:
    out.WriteAs<int8_t>(intensityImageChannel);

    // New in v7:
    out << hasPixelLabels();
    if (hasPixelLabels())
    {
        pixelLabels->writeToStream(out);
    }

    // v10:
    out.WriteAs<uint8_t>(rangeImageOtherLayers.size());
    for (const auto& kv : rangeImageOtherLayers)
    {
        out << kv.first;
        const auto& ri = kv.second;
        out.WriteAs<uint32_t>(ri.cols());
        out.WriteAs<uint32_t>(ri.rows());
        if (!ri.empty())
            out.WriteBufferFixEndianness<uint16_t>(ri.data(), ri.size());
    }
}

void CObservation3DRangeScan::serializeFrom(
    mrpt::serialization::CArchive& in, uint8_t version)
{
    switch (version)
    {
        case 0:
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:
        case 6:
        case 7:
        case 8:
        case 9:
        case 10:
        {
            uint32_t N;

            in >> maxRange >> sensorPose;

            if (version > 0)
                in >> hasPoints3D;
            else
                hasPoints3D = true;

            if (hasPoints3D)
            {
                in >> N;
                resizePoints3DVectors(N);

                if (N)
                {
                    in.ReadBufferFixEndianness(&points3D_x[0], N);
                    in.ReadBufferFixEndianness(&points3D_y[0], N);
                    in.ReadBufferFixEndianness(&points3D_z[0], N);

                    if (version == 0)
                    {
                        vector<char> validRange(N);  // for v0.
                        in.ReadBuffer(
                            &validRange[0], sizeof(validRange[0]) * N);
                    }
                    if (version >= 8)
                    {
                        in.ReadBufferFixEndianness(&points3D_idxs_x[0], N);
                        in.ReadBufferFixEndianness(&points3D_idxs_y[0], N);
                    }
                }
            }
            else
            {
                this->resizePoints3DVectors(0);
            }

            if (version >= 1)
            {
                in >> hasRangeImage;
                if (version >= 9)
                    in >> rangeUnits;
                else
                    rangeUnits = 1e-3f;  // default units

                if (hasRangeImage)
                {
                    if (version < 9)
                    {
                        // Convert from old format:
                        mrpt::math::CMatrixF ri;
                        in >> ri;
                        const uint32_t rows = ri.rows(), cols = ri.cols();
                        ASSERT_(rows > 0 && cols > 0);

                        // Call "rangeImage_setSize()" to exploit the mempool:
                        rangeImage_setSize(rows, cols);

                        for (uint32_t r = 0; r < rows; r++)
                            for (uint32_t c = 0; c < cols; c++)
                                rangeImage(r, c) = static_cast<uint16_t>(
                                    mrpt::round(ri(r, c) / rangeUnits));
                    }
                    else
                    {
                        const uint32_t rows = in.ReadAs<uint32_t>();
                        const uint32_t cols = in.ReadAs<uint32_t>();

                        // Call "rangeImage_setSize()" to exploit the mempool:
                        rangeImage_setSize(rows, cols);

                        // new v9:
                        if (rangeImage.size() != 0)
                            in.ReadBufferFixEndianness<uint16_t>(
                                rangeImage.data(), rangeImage.size());
                    }
                }

                in >> hasIntensityImage;
                if (hasIntensityImage) in >> intensityImage;

                in >> hasConfidenceImage;
                if (hasConfidenceImage) in >> confidenceImage;

                if (version >= 2)
                {
                    in >> cameraParams;

                    if (version >= 4)
                    {
                        in >> cameraParamsIntensity >>
                            relativePoseIntensityWRTDepth;
                    }
                    else
                    {
                        cameraParamsIntensity = cameraParams;
                        relativePoseIntensityWRTDepth = CPose3D();
                    }
                }
            }

            in >> stdError;
            in >> timestamp;
            in >> sensorLabel;

            if (version >= 3)
            {
                // New in v3:
                in >> m_points3D_external_stored >> m_points3D_external_file;
                in >> m_rangeImage_external_stored >>
                    m_rangeImage_external_file;
            }
            else
            {
                m_points3D_external_stored = false;
                m_rangeImage_external_stored = false;
            }

            if (version >= 5)
            {
                in >> range_is_depth;
            }
            else
            {
                range_is_depth = true;
            }

            if (version >= 6)
            {
                int8_t i;
                in >> i;
                intensityImageChannel = static_cast<TIntensityChannelID>(i);
            }
            else
            {
                intensityImageChannel = CH_VISIBLE;
            }

            pixelLabels.reset();  // Remove existing data first (_unique() is to
            // leave alive any user copies of the shared
            // pointer).
            if (version >= 7)
            {
                bool do_have_labels;
                in >> do_have_labels;

                if (do_have_labels)
                    pixelLabels.reset(
                        TPixelLabelInfoBase::readAndBuildFromStream(in));
            }

            rangeImageOtherLayers.clear();
            if (version >= 10)
            {
                const auto numLayers = in.ReadAs<uint8_t>();
                for (size_t i = 0; i < numLayers; i++)
                {
                    std::string name;
                    in >> name;
                    auto& ri = rangeImageOtherLayers[name];

                    const uint32_t rows = in.ReadAs<uint32_t>();
                    const uint32_t cols = in.ReadAs<uint32_t>();
                    ri.resize(rows, cols);
                    if (ri.size() != 0)
                        in.ReadBufferFixEndianness<uint16_t>(
                            ri.data(), ri.size());
                }
            }

            // auto-fix wrong camera resolution in parameters:
            if (hasRangeImage &&
                (static_cast<int>(cameraParams.ncols) != rangeImage.cols() ||
                 static_cast<int>(cameraParams.nrows) != rangeImage.rows()))
            {
                std::cerr << "[CObservation3DRangeScan] Warning: autofixing "
                             "incorrect camera resolution in TCamera:"
                          << cameraParams.ncols << "x" << cameraParams.nrows
                          << " => " << rangeImage.cols() << "x"
                          << rangeImage.rows() << "\n";
                cameraParams.ncols = rangeImage.cols();
                cameraParams.nrows = rangeImage.rows();
            }
        }
        break;
        default:
            MRPT_THROW_UNKNOWN_SERIALIZATION_VERSION(version);
    };
}

void CObservation3DRangeScan::swap(CObservation3DRangeScan& o)
{
    CObservation::swap(o);

    std::swap(hasPoints3D, o.hasPoints3D);
    points3D_x.swap(o.points3D_x);
    points3D_y.swap(o.points3D_y);
    points3D_z.swap(o.points3D_z);
    points3D_idxs_x.swap(o.points3D_idxs_x);
    points3D_idxs_y.swap(o.points3D_idxs_y);
    std::swap(m_points3D_external_stored, o.m_points3D_external_stored);
    std::swap(m_points3D_external_file, o.m_points3D_external_file);

    std::swap(hasRangeImage, o.hasRangeImage);
    rangeImage.swap(o.rangeImage);
    std::swap(m_rangeImage_external_stored, o.m_rangeImage_external_stored);
    std::swap(m_rangeImage_external_file, o.m_rangeImage_external_file);

    std::swap(hasIntensityImage, o.hasIntensityImage);
    std::swap(intensityImageChannel, o.intensityImageChannel);
    intensityImage.swap(o.intensityImage);

    std::swap(hasConfidenceImage, o.hasConfidenceImage);
    confidenceImage.swap(o.confidenceImage);

    std::swap(pixelLabels, o.pixelLabels);

    std::swap(relativePoseIntensityWRTDepth, o.relativePoseIntensityWRTDepth);

    std::swap(cameraParams, o.cameraParams);
    std::swap(cameraParamsIntensity, o.cameraParamsIntensity);

    std::swap(maxRange, o.maxRange);
    std::swap(sensorPose, o.sensorPose);
    std::swap(stdError, o.stdError);

    rangeImageOtherLayers.swap(o.rangeImageOtherLayers);
}

void CObservation3DRangeScan::load() const
{
    if (hasPoints3D && m_points3D_external_stored)
    {
        const string fil = points3D_getExternalStorageFileAbsolutePath();
        if (mrpt::system::strCmpI(
                "txt", mrpt::system::extractFileExtension(fil, true)))
        {
            CMatrixFloat M;
            M.loadFromTextFile(fil);
            ASSERT_EQUAL_(M.rows(), 3);
            const auto N = M.cols();

            auto& xs = const_cast<std::vector<float>&>(points3D_x);
            auto& ys = const_cast<std::vector<float>&>(points3D_y);
            auto& zs = const_cast<std::vector<float>&>(points3D_z);
            xs.resize(N);
            ys.resize(N);
            zs.resize(N);
            std::memcpy(&xs[0], &M(0, 0), sizeof(float) * N);
            std::memcpy(&ys[0], &M(1, 0), sizeof(float) * N);
            std::memcpy(&zs[0], &M(2, 0), sizeof(float) * N);
        }
        else
        {
            mrpt::io::CFileGZInputStream fi(fil);
            auto f = mrpt::serialization::archiveFrom(fi);
            f >> const_cast<std::vector<float>&>(points3D_x) >>
                const_cast<std::vector<float>&>(points3D_y) >>
                const_cast<std::vector<float>&>(points3D_z);
        }
    }

    if (hasRangeImage && m_rangeImage_external_stored)
    {
        for (size_t idx = 0; idx < 1 + rangeImageOtherLayers.size(); idx++)
        {
            std::string layerName;
            mrpt::math::CMatrix_u16* ri = nullptr;
            if (idx == 0)
                ri = const_cast<mrpt::math::CMatrix_u16*>(&rangeImage);
            else
            {
                auto it = rangeImageOtherLayers.begin();
                std::advance(it, idx - 1);
                layerName = it->first;
                ri = const_cast<mrpt::math::CMatrix_u16*>(&it->second);
            }
            const string fil =
                rangeImage_getExternalStorageFileAbsolutePath(layerName);
            if (mrpt::system::strCmpI(
                    "txt", mrpt::system::extractFileExtension(fil, true)))
            {
                ri->loadFromTextFile(fil);
            }
            else
            {
                auto& me = const_cast<CObservation3DRangeScan&>(*this);

                mrpt::io::CFileGZInputStream fi(fil);
                auto f = mrpt::serialization::archiveFrom(fi);
                const uint32_t rows = f.ReadAs<uint32_t>();
                const uint32_t cols = f.ReadAs<uint32_t>();
                me.rangeImage_setSize(rows, cols);
                if (ri->size() != 0)
                    f.ReadBufferFixEndianness<uint16_t>(ri->data(), ri->size());
            }

        }  // end for each layer
    }
}

void CObservation3DRangeScan::unload()
{
    if (hasPoints3D && m_points3D_external_stored)
    {
        mrpt::vector_strong_clear(points3D_x);
        mrpt::vector_strong_clear(points3D_y);
        mrpt::vector_strong_clear(points3D_z);
    }

    if (hasRangeImage && m_rangeImage_external_stored) rangeImage.setSize(0, 0);

    intensityImage.unload();
    confidenceImage.unload();
}

std::string CObservation3DRangeScan::rangeImage_getExternalStorageFile(
    const std::string& rangeImageLayer) const
{
    std::string filName = m_rangeImage_external_file;
    if (!rangeImageLayer.empty())
    {
        const auto curExt = mrpt::system::extractFileExtension(filName);
        mrpt::system::fileNameChangeExtension(
            filName, std::string("layer_") + rangeImageLayer + curExt);
    }
    return filName;
}

void CObservation3DRangeScan::rangeImage_getExternalStorageFileAbsolutePath(
    std::string& out_path, const std::string& rangeImageLayer) const
{
    std::string filName = rangeImage_getExternalStorageFile(rangeImageLayer);

    ASSERT_(filName.size() > 2);
    if (filName[0] == '/' || (filName[1] == ':' && filName[2] == '\\'))
    {
        out_path = filName;
    }
    else
    {
        out_path = CImage::getImagesPathBase();
        size_t N = CImage::getImagesPathBase().size() - 1;
        if (CImage::getImagesPathBase()[N] != '/' &&
            CImage::getImagesPathBase()[N] != '\\')
            out_path += "/";
        out_path += filName;
    }
}
void CObservation3DRangeScan::points3D_getExternalStorageFileAbsolutePath(
    std::string& out_path) const
{
    ASSERT_(m_points3D_external_file.size() > 2);
    if (m_points3D_external_file[0] == '/' ||
        (m_points3D_external_file[1] == ':' &&
         m_points3D_external_file[2] == '\\'))
    {
        out_path = m_points3D_external_file;
    }
    else
    {
        out_path = CImage::getImagesPathBase();
        size_t N = CImage::getImagesPathBase().size() - 1;
        if (CImage::getImagesPathBase()[N] != '/' &&
            CImage::getImagesPathBase()[N] != '\\')
            out_path += "/";
        out_path += m_points3D_external_file;
    }
}

void CObservation3DRangeScan::points3D_convertToExternalStorage(
    const std::string& fileName_, const std::string& use_this_base_dir)
{
    ASSERT_(!points3D_isExternallyStored());
    ASSERT_(
        points3D_x.size() == points3D_y.size() &&
        points3D_x.size() == points3D_z.size());

    if (EXTERNALS_AS_TEXT_value)
        m_points3D_external_file =
            mrpt::system::fileNameChangeExtension(fileName_, "txt");
    else
        m_points3D_external_file =
            mrpt::system::fileNameChangeExtension(fileName_, "bin");

    // Use "use_this_base_dir" in "*_getExternalStorageFileAbsolutePath()"
    // instead of CImage::getImagesPathBase()
    const string savedDir = CImage::getImagesPathBase();
    CImage::setImagesPathBase(use_this_base_dir);
    const string real_absolute_path =
        points3D_getExternalStorageFileAbsolutePath();
    CImage::setImagesPathBase(savedDir);

    if (EXTERNALS_AS_TEXT_value)
    {
        const size_t nPts = points3D_x.size();

        CMatrixFloat M(3, nPts);
        M.setRow(0, points3D_x);
        M.setRow(1, points3D_y);
        M.setRow(2, points3D_z);

        M.saveToTextFile(real_absolute_path, MATRIX_FORMAT_FIXED);
    }
    else
    {
        mrpt::io::CFileGZOutputStream fo(real_absolute_path);
        auto f = mrpt::serialization::archiveFrom(fo);
        f << points3D_x << points3D_y << points3D_z;
    }

    m_points3D_external_stored = true;

    // Really dealloc memory, clear() is not enough:
    vector_strong_clear(points3D_x);
    vector_strong_clear(points3D_y);
    vector_strong_clear(points3D_z);
    vector_strong_clear(points3D_idxs_x);
    vector_strong_clear(points3D_idxs_y);
}
void CObservation3DRangeScan::rangeImage_convertToExternalStorage(
    const std::string& fileName_, const std::string& use_this_base_dir)
{
    ASSERT_(!rangeImage_isExternallyStored());
    if (EXTERNALS_AS_TEXT_value)
        m_rangeImage_external_file =
            mrpt::system::fileNameChangeExtension(fileName_, "txt");
    else
        m_rangeImage_external_file =
            mrpt::system::fileNameChangeExtension(fileName_, "bin");

    // Use "use_this_base_dir" in "*_getExternalStorageFileAbsolutePath()"
    // instead of CImage::getImagesPathBase()
    const string savedDir = CImage::getImagesPathBase();
    CImage::setImagesPathBase(use_this_base_dir);

    for (size_t idx = 0; idx < 1 + rangeImageOtherLayers.size(); idx++)
    {
        std::string layerName;
        mrpt::math::CMatrix_u16* ri = nullptr;
        if (idx == 0)
            ri = &rangeImage;
        else
        {
            auto it = rangeImageOtherLayers.begin();
            std::advance(it, idx - 1);
            layerName = it->first;
            ri = &it->second;
        }
        const string real_absolute_path =
            rangeImage_getExternalStorageFileAbsolutePath(layerName);

        if (EXTERNALS_AS_TEXT_value)
        {
            ri->saveToTextFile(real_absolute_path, MATRIX_FORMAT_FIXED);
        }
        else
        {
            mrpt::io::CFileGZOutputStream fo(real_absolute_path);
            auto f = mrpt::serialization::archiveFrom(fo);

            f.WriteAs<uint32_t>(ri->rows());
            f.WriteAs<uint32_t>(ri->cols());
            if (ri->size() != 0)
                f.WriteBufferFixEndianness<uint16_t>(ri->data(), ri->size());
        }
    }

    m_rangeImage_external_stored = true;
    rangeImage.setSize(0, 0);

    CImage::setImagesPathBase(savedDir);
}

// Auxiliary function for "recoverCameraCalibrationParameters"
#define CALIB_DECIMAT 15

namespace mrpt::obs::detail
{
struct TLevMarData
{
    const CObservation3DRangeScan& obs;
    const double z_offset;
    TLevMarData(const CObservation3DRangeScan& obs_, const double z_offset_)
        : obs(obs_), z_offset(z_offset_)
    {
    }
};

static void cam2vec(const TCamera& camPar, CVectorDouble& x)
{
    if (x.size() < 4 + 4) x.resize(4 + 4);

    x[0] = camPar.fx();
    x[1] = camPar.fy();
    x[2] = camPar.cx();
    x[3] = camPar.cy();

    for (size_t i = 0; i < 4; i++) x[4 + i] = camPar.dist[i];
}
static void vec2cam(const CVectorDouble& x, TCamera& camPar)
{
    camPar.intrinsicParams(0, 0) = x[0];  // fx
    camPar.intrinsicParams(1, 1) = x[1];  // fy
    camPar.intrinsicParams(0, 2) = x[2];  // cx
    camPar.intrinsicParams(1, 2) = x[3];  // cy

    for (size_t i = 0; i < 4; i++) camPar.dist[i] = x[4 + i];
}
static void cost_func(
    const CVectorDouble& par, const TLevMarData& d, CVectorDouble& err)
{
    const CObservation3DRangeScan& obs = d.obs;

    TCamera params;
    vec2cam(par, params);

    const size_t nC = obs.rangeImage.cols();
    const size_t nR = obs.rangeImage.rows();

    err = CVectorDouble();  // .resize( nC*nR/square(CALIB_DECIMAT) );

    for (size_t r = 0; r < nR; r += CALIB_DECIMAT)
    {
        for (size_t c = 0; c < nC; c += CALIB_DECIMAT)
        {
            const size_t idx = nC * r + c;

            TPoint3D p(
                obs.points3D_x[idx] + d.z_offset, obs.points3D_y[idx],
                obs.points3D_z[idx]);
            TPoint3D P(-p.y, -p.z, p.x);
            TPixelCoordf pixel;
            {  // mrpt-obs shouldn't depend on mrpt-vision just for this!
                // pinhole::projectPoint_with_distortion(p_wrt_cam,cam,pixel);

                // Pinhole model:
                const double x = P.x / P.z;
                const double y = P.y / P.z;

                // Radial distortion:
                const double r2 = square(x) + square(y);
                const double r4 = square(r2);

                pixel.x = mrpt::d2f(
                    params.cx() +
                    params.fx() *
                        (x * (1 + params.dist[0] * r2 + params.dist[1] * r4 +
                              2 * params.dist[2] * x * y +
                              params.dist[3] * (r2 + 2 * square(x)))));
                pixel.y = mrpt::d2f(
                    params.cy() +
                    params.fy() *
                        (y * (1 + params.dist[0] * r2 + params.dist[1] * r4 +
                              2 * params.dist[3] * x * y +
                              params.dist[2] * (r2 + 2 * square(y)))));
            }

            // In theory, it should be (r,c):
            err.push_back(c - pixel.x);
            err.push_back(r - pixel.y);
        }
    }
}  // end error_func
}  // namespace mrpt::obs::detail

/** A Levenberg-Marquart-based optimizer to recover the calibration parameters
 * of a 3D camera given a range (depth) image and the corresponding 3D point
 * cloud.
 * \param camera_offset The offset (in meters) in the +X direction of the point
 * cloud. It's 1cm for SwissRanger SR4000.
 * \return The final average reprojection error per pixel (typ <0.05 px)
 */
double CObservation3DRangeScan::recoverCameraCalibrationParameters(
    const CObservation3DRangeScan& obs, mrpt::img::TCamera& out_camParams,
    const double camera_offset)
{
    MRPT_START

    ASSERT_(obs.hasRangeImage && obs.hasPoints3D);
    ASSERT_(
        obs.points3D_x.size() == obs.points3D_y.size() &&
        obs.points3D_x.size() == obs.points3D_z.size());

    using TMyLevMar =
        CLevenbergMarquardtTempl<CVectorDouble, detail::TLevMarData>;
    TMyLevMar::TResultInfo info;

    const size_t nR = obs.rangeImage.rows();
    const size_t nC = obs.rangeImage.cols();

    TCamera camInit;
    camInit.ncols = nC;
    camInit.nrows = nR;
    camInit.intrinsicParams(0, 0) = 250;
    camInit.intrinsicParams(1, 1) = 250;
    camInit.intrinsicParams(0, 2) = nC >> 1;
    camInit.intrinsicParams(1, 2) = nR >> 1;

    CVectorDouble initial_x;
    detail::cam2vec(camInit, initial_x);

    initial_x.resize(8);
    CVectorDouble increments_x(initial_x.size());
    increments_x.fill(1e-4);

    CVectorDouble optimal_x;

    TMyLevMar lm;
    lm.execute(
        optimal_x, initial_x, &mrpt::obs::detail::cost_func, increments_x,
        detail::TLevMarData(obs, camera_offset), info,
        mrpt::system::LVL_INFO, /* verbose */
        1000, /* max iter */
        1e-3, 1e-9, 1e-9, false);

    const double avr_px_err =
        sqrt(info.final_sqr_err / double(nC * nR) / square(CALIB_DECIMAT));

    out_camParams.ncols = nC;
    out_camParams.nrows = nR;
    out_camParams.focalLengthMeters = camera_offset;
    detail::vec2cam(optimal_x, out_camParams);

    return avr_px_err;

    MRPT_END
}

void CObservation3DRangeScan::getZoneAsObs(
    CObservation3DRangeScan& obs, const unsigned int& r1,
    const unsigned int& r2, const unsigned int& c1, const unsigned int& c2)
{
    unsigned int cols = cameraParams.ncols;
    unsigned int rows = cameraParams.nrows;

    ASSERT_((r1 < r2) && (c1 < c2));
    ASSERT_((r2 < rows) && (c2 < cols));
    // Maybe we needed to copy more base obs atributes

    // Copy zone of range image
    obs.hasRangeImage = hasRangeImage;
    if (hasRangeImage)
        obs.rangeImage = rangeImage.asEigen().block(r2 - r1, c2 - c1, r1, c1);

    // Copy zone of intensity image
    obs.hasIntensityImage = hasIntensityImage;
    obs.intensityImageChannel = intensityImageChannel;
    if (hasIntensityImage)
        intensityImage.extract_patch(
            obs.intensityImage, c1, r1, c2 - c1, r2 - r1);

    // Copy zone of confidence image
    obs.hasConfidenceImage = hasConfidenceImage;
    if (hasConfidenceImage)
        confidenceImage.extract_patch(
            obs.confidenceImage, c1, r1, c2 - c1, r2 - r1);

    // Zone labels: It's too complex, just document that pixel labels are NOT
    // extracted.

    // Copy zone of scanned points
    obs.hasPoints3D = hasPoints3D;
    if (hasPoints3D)
    {
        // Erase a possible previous content
        if (obs.points3D_x.size() > 0)
        {
            obs.points3D_x.clear();
            obs.points3D_y.clear();
            obs.points3D_z.clear();
        }

        for (unsigned int i = r1; i < r2; i++)
            for (unsigned int j = c1; j < c2; j++)
            {
                obs.points3D_x.push_back(points3D_x.at(cols * i + j));
                obs.points3D_y.push_back(points3D_y.at(cols * i + j));
                obs.points3D_z.push_back(points3D_z.at(cols * i + j));
            }
    }

    obs.maxRange = maxRange;
    obs.sensorPose = sensorPose;
    obs.stdError = stdError;

    obs.cameraParams = cameraParams;
}

/** Use this method instead of resizing all three \a points3D_x, \a points3D_y &
 * \a points3D_z to allow the usage of the internal memory pool. */
void CObservation3DRangeScan::resizePoints3DVectors(const size_t WH)
{
#ifdef COBS3DRANGE_USE_MEMPOOL
    // If WH=0 this is a clear:
    if (!WH)
    {
        vector_strong_clear(points3D_x);
        vector_strong_clear(points3D_y);
        vector_strong_clear(points3D_z);
        vector_strong_clear(points3D_idxs_x);
        vector_strong_clear(points3D_idxs_y);
        return;
    }

    if (WH <= points3D_x.size())  // reduce size, don't realloc
    {
        points3D_x.resize(WH);
        points3D_y.resize(WH);
        points3D_z.resize(WH);
        points3D_idxs_x.resize(WH);
        points3D_idxs_y.resize(WH);
        return;
    }

    // Request memory for the X,Y,Z buffers from the memory pool:
    TMyPointsMemPool* pool = TMyPointsMemPool::getInstance();
    if (pool)
    {
        CObservation3DRangeScan_Points_MemPoolParams mem_params;
        mem_params.WH = WH;

        CObservation3DRangeScan_Points_MemPoolData* mem_block =
            pool->request_memory(mem_params);

        if (mem_block)
        {  // Take the memory via swaps:
            points3D_x.swap(mem_block->pts_x);
            points3D_y.swap(mem_block->pts_y);
            points3D_z.swap(mem_block->pts_z);
            points3D_idxs_x.swap(mem_block->idxs_x);
            points3D_idxs_y.swap(mem_block->idxs_y);
            delete mem_block;
        }
    }
#endif

    // Either if there was no pool memory or we got it, make sure the size of
    // vectors is OK:
    points3D_x.resize(WH);
    points3D_y.resize(WH);
    points3D_z.resize(WH);
    points3D_idxs_x.resize(WH);
    points3D_idxs_y.resize(WH);
}

size_t CObservation3DRangeScan::getScanSize() const
{
    // x,y,z vectors have the same size.
    return points3D_x.size();
}

// Similar to calling "rangeImage.setSize(H,W)" but this method provides memory
// pooling to speed-up the memory allocation.
void CObservation3DRangeScan::rangeImage_setSize(const int H, const int W)
{
    bool ri_done = rangeImage.cols() == W && rangeImage.rows() == H;

#ifdef COBS3DRANGE_USE_MEMPOOL
    // Request memory from the memory pool:
    TMyRangesMemPool* pool = TMyRangesMemPool::getInstance();
    if (pool && !ri_done)
    {
        CObservation3DRangeScan_Ranges_MemPoolParams mem_params;
        mem_params.H = H;
        mem_params.W = W;

        CObservation3DRangeScan_Ranges_MemPoolData* mem_block =
            pool->request_memory(mem_params);

        if (mem_block)
        {  // Take the memory via swaps:
            rangeImage.swap(mem_block->rangeImage);
            delete mem_block;
            ri_done = true;
        }
    }
// otherwise, continue with the normal method:
#endif
    // Fall-back to normal method:
    if (!ri_done) rangeImage.setSize(H, W);

    // and in all cases, do the resize for the other layers:
    for (auto& layer : rangeImageOtherLayers) layer.second.setSize(H, W);
}

// Return true if \a relativePoseIntensityWRTDepth equals the pure rotation
// (0,0,0,-90deg,0,-90deg) (with a small comparison epsilon)
bool CObservation3DRangeScan::doDepthAndIntensityCamerasCoincide() const
{
    static const double EPSILON = 1e-7;
    static mrpt::poses::CPose3D ref_pose(0, 0, 0, -90.0_deg, 0, -90.0_deg);

    return (relativePoseIntensityWRTDepth.m_coords.array().abs() < EPSILON)
               .all() &&
           ((ref_pose.getRotationMatrix() -
             relativePoseIntensityWRTDepth.getRotationMatrix())
                .array()
                .abs() < EPSILON)
               .all();
}

void CObservation3DRangeScan::convertTo2DScan(
    mrpt::obs::CObservation2DRangeScan& out_scan2d,
    const T3DPointsTo2DScanParams& sp, const TRangeImageFilterParams& fp)
{
    out_scan2d.sensorLabel = sensorLabel;
    out_scan2d.timestamp = this->timestamp;

    if (!this->hasRangeImage)
    {  // Nothing to do!
        out_scan2d.resizeScan(0);
        return;
    }

    const size_t nCols = this->rangeImage.cols();
    const size_t nRows = this->rangeImage.rows();
    if (fp.rangeMask_min)
    {  // sanity check:
        ASSERT_EQUAL_(fp.rangeMask_min->cols(), rangeImage.cols());
        ASSERT_EQUAL_(fp.rangeMask_min->rows(), rangeImage.rows());
    }
    if (fp.rangeMask_max)
    {  // sanity check:
        ASSERT_EQUAL_(fp.rangeMask_max->cols(), rangeImage.cols());
        ASSERT_EQUAL_(fp.rangeMask_max->rows(), rangeImage.rows());
    }

    // Compute the real horizontal FOV from the range camera intrinsic calib
    // data:
    // Note: this assumes the range image has been "undistorted", which is true
    // for data
    //        from OpenNI, and will be in the future for libfreenect in MRPT,
    //        but it's
    //        not implemented yet (as of Mar 2012), so this is an approximation
    //        in that case.
    const double cx = this->cameraParams.cx();
    const double cy = this->cameraParams.cy();
    const double fx = this->cameraParams.fx();
    const double fy = this->cameraParams.fy();

    // (Imagine the camera seen from above to understand this geometry)
    const double real_FOV_left = atan2(cx, fx);
    const double real_FOV_right = atan2(nCols - 1 - cx, fx);

    // FOV of the equivalent "fake" "laser scanner":
    const float FOV_equiv =
        mrpt::d2f(2 * std::max(real_FOV_left, real_FOV_right));

    // Now, we should create more "fake laser" points than columns in the image,
    //  since laser scans are assumed to sample space at evenly-spaced angles,
    //  while in images it is like ~tan(angle).
    ASSERT_ABOVE_(
        sp.oversampling_ratio, (sp.use_origin_sensor_pose ? 0.0 : 1.0));
    const auto nLaserRays = static_cast<size_t>(nCols * sp.oversampling_ratio);

    // Prepare 2D scan data fields:
    out_scan2d.aperture = FOV_equiv;
    out_scan2d.maxRange = this->maxRange;
    out_scan2d.resizeScan(nLaserRays);

    // default: all ranges=invalid
    out_scan2d.resizeScanAndAssign(nLaserRays, 2.0f * this->maxRange, false);
    if (sp.use_origin_sensor_pose)
        out_scan2d.sensorPose = mrpt::poses::CPose3D();
    else
        out_scan2d.sensorPose = this->sensorPose;

    // The vertical FOVs given by the user can be translated into limits of the
    // tangents (tan>0 means above, i.e. z>0):
    const float tan_min = mrpt::d2f(-tan(std::abs(sp.angle_inf)));
    const float tan_max = mrpt::d2f(tan(std::abs(sp.angle_sup)));

    // Precompute the tangents of the vertical angles of each "ray"
    // for every row in the range image:
    std::vector<float> vert_ang_tan(nRows);
    for (size_t r = 0; r < nRows; r++) vert_ang_tan[r] = d2f((cy - r) / fy);

    if (!sp.use_origin_sensor_pose)
    {
        // Algorithm 1: each column in the range image corresponds to a known
        // orientation in the 2D scan:
        // -------------------
        out_scan2d.rightToLeft = false;

        // Angle "counter" for the fake laser scan direction, and the increment:
        double ang = -FOV_equiv * 0.5;
        const double A_ang = FOV_equiv / (nLaserRays - 1);

        TRangeImageFilter rif(fp);

        // Go thru columns, and keep the minimum distance (along the +X axis,
        // not 3D distance!)
        // for each direction (i.e. for each column) which also lies within the
        // vertical FOV passed
        // by the user.
        for (size_t i = 0; i < nLaserRays; i++, ang += A_ang)
        {
            // Equivalent column in the range image for the "i'th" ray:
            const double tan_ang = tan(ang);
            // make sure we don't go out of range (just in case):
            const size_t c = std::min(
                static_cast<size_t>(std::max(0.0, cx + fx * tan_ang)),
                nCols - 1);

            bool any_valid = false;
            float closest_range = out_scan2d.maxRange;

            for (size_t r = 0; r < nRows; r++)
            {
                const float D = rangeImage.coeff(r, c) * rangeUnits;
                if (!rif.do_range_filter(r, c, D)) continue;

                // All filters passed:
                const float this_point_tan = vert_ang_tan[r] * D;
                if (this_point_tan > tan_min && this_point_tan < tan_max)
                {
                    any_valid = true;
                    mrpt::keep_min(closest_range, D);
                }
            }

            if (any_valid)
            {
                out_scan2d.setScanRangeValidity(i, true);
                // Compute the distance in 2D from the "depth" in closest_range:
                out_scan2d.setScanRange(
                    i, mrpt::d2f(
                           closest_range * std::sqrt(1.0 + tan_ang * tan_ang)));
            }
        }  // end for columns
    }
    else
    {
        // Algorithm 2: project to 3D and reproject (for a different sensorPose
        // at the origin)
        // ------------------------------------------------------------------------
        out_scan2d.rightToLeft = true;

        T3DPointsProjectionParams projParams;
        projParams.takeIntoAccountSensorPoseOnRobot = true;

        mrpt::opengl::CPointCloud::Ptr pc = mrpt::opengl::CPointCloud::Create();
        this->unprojectInto(*pc, projParams, fp);

        const std::vector<mrpt::math::TPoint3Df>& pts = pc->getArrayPoints();
        const size_t N = pts.size();

        const double A_ang = FOV_equiv / (nLaserRays - 1);
        const double ang0 = -FOV_equiv * 0.5;

        for (size_t i = 0; i < N; i++)
        {
            if (pts[i].z < sp.z_min || pts[i].z > sp.z_max) continue;

            const double phi_wrt_origin = atan2(pts[i].y, pts[i].x);

            int i_range = mrpt::round((phi_wrt_origin - ang0) / A_ang);
            if (i_range < 0 || i_range >= int(nLaserRays)) continue;

            const float r_wrt_origin = ::hypotf(pts[i].x, pts[i].y);
            if (out_scan2d.getScanRange(i_range) > r_wrt_origin)
                out_scan2d.setScanRange(i_range, r_wrt_origin);
            out_scan2d.setScanRangeValidity(i_range, true);
        }
    }
}

void CObservation3DRangeScan::getDescriptionAsText(std::ostream& o) const
{
    CObservation::getDescriptionAsText(o);

    this->load();  // Make sure the 3D point cloud, etc... are all loaded in
    // memory.

    o << "Homogeneous matrix for the sensor's 3D pose, relative to robot "
         "base:\n";
    o << sensorPose.getHomogeneousMatrixVal<CMatrixDouble44>() << sensorPose
      << "\n";

    o << "maxRange = " << maxRange << " [meters]"
      << "\n";
    o << "rangeUnits = " << rangeUnits << " [meters]"
      << "\n";

    o << "Has 3D point cloud? ";
    if (hasPoints3D)
    {
        o << "YES: " << points3D_x.size() << " points";
        if (points3D_isExternallyStored())
            o << ". External file: " << points3D_getExternalStorageFile()
              << "\n";
        else
            o << " (embedded)."
              << "\n";
    }
    else
        o << "NO"
          << "\n";

    o << "Range is depth: " << (range_is_depth ? "YES" : "NO") << "\n";
    o << "Has raw range data? " << (hasRangeImage ? "YES" : "NO");
    if (hasRangeImage)
    {
        if (rangeImage_isExternallyStored())
            o << ". External file: " << rangeImage_getExternalStorageFile("");
        else
            o << " (embedded).";
    }
    o << "\n";

    for (auto& layer : rangeImageOtherLayers)
    {
        o << "Additional rangeImage layer: '" << layer.first << "'";
        if (rangeImage_isExternallyStored())
            o << ". External file: " << rangeImage_getExternalStorageFile("");
        else
            o << " (embedded).";
        o << "\n";
    }

    o << "\n"
      << "Has intensity data? " << (hasIntensityImage ? "YES" : "NO");
    if (hasIntensityImage)
    {
        if (intensityImage.isExternallyStored())
            o << ". External file: " << intensityImage.getExternalStorageFile()
              << "\n";
        else
            o << " (embedded).\n";
        // Channel?
        o << "Source channel: "
          << mrpt::typemeta::TEnumType<
                 CObservation3DRangeScan::TIntensityChannelID>::
                 value2name(intensityImageChannel)
          << "\n";
    }

    o << "\n"
      << "Has confidence data? " << (hasConfidenceImage ? "YES" : "NO");
    if (hasConfidenceImage)
    {
        if (confidenceImage.isExternallyStored())
            o << ". External file: " << confidenceImage.getExternalStorageFile()
              << "\n";
        else
            o << " (embedded)."
              << "\n";
    }

    o << "\n"
      << "Has pixel labels? " << (hasPixelLabels() ? "YES" : "NO");
    if (hasPixelLabels())
    {
        o << " Human readable labels:"
          << "\n";
        for (auto it = pixelLabels->pixelLabelNames.begin();
             it != pixelLabels->pixelLabelNames.end(); ++it)
            o << " label[" << it->first << "]: '" << it->second << "'"
              << "\n";
    }

    o << "\n"
      << "\n";
    o << "Depth camera calibration parameters:"
      << "\n";
    {
        CConfigFileMemory cfg;
        cameraParams.saveToConfigFile("DEPTH_CAM_PARAMS", cfg);
        o << cfg.getContent() << "\n";
    }
    o << "\n"
      << "Intensity camera calibration parameters:"
      << "\n";
    {
        CConfigFileMemory cfg;
        cameraParamsIntensity.saveToConfigFile("INTENSITY_CAM_PARAMS", cfg);
        o << cfg.getContent() << "\n";
    }
    o << "\n"
      << "\n"
      << "Pose of the intensity cam. wrt the depth cam:\n"
      << relativePoseIntensityWRTDepth << "\n"
      << relativePoseIntensityWRTDepth
             .getHomogeneousMatrixVal<CMatrixDouble44>()
      << "\n";
}

T3DPointsTo2DScanParams::T3DPointsTo2DScanParams()
    : angle_sup(mrpt::DEG2RAD(5)),
      angle_inf(mrpt::DEG2RAD(5)),
      z_min(-std::numeric_limits<double>::max()),
      z_max(std::numeric_limits<double>::max())
{
}

void CObservation3DRangeScan::undistort()
{
#if MRPT_HAS_OPENCV

    // DEPTH image:
    {
        // OpenCV wrapper (copy-less) for rangeImage:

        const cv::Mat distortion(
            1, cameraParams.dist.size(), CV_64F, &cameraParams.dist[0]);
        const cv::Mat intrinsics(
            3, 3, CV_64F, &cameraParams.intrinsicParams(0, 0));

        const auto imgSize = cv::Size(rangeImage.rows(), rangeImage.cols());

        double alpha = 0;  // all depth pixels are visible in the output
        const cv::Mat newIntrinsics = cv::getOptimalNewCameraMatrix(
            intrinsics, distortion, imgSize, alpha);

        cv::Mat outRangeImg(rangeImage.rows(), rangeImage.cols(), CV_16UC1);

        // Undistort:
        const cv::Mat R_eye = cv::Mat::eye(3, 3, CV_32FC1);

        cv::Mat m1, m2;

        cv::initUndistortRectifyMap(
            intrinsics, distortion, R_eye, newIntrinsics, imgSize, CV_32FC1, m1,
            m2);

        for (size_t idx = 0; idx < 1 + rangeImageOtherLayers.size(); idx++)
        {
            mrpt::math::CMatrix_u16* ri = nullptr;
            if (idx == 0)
                ri = &rangeImage;
            else
            {
                auto it = rangeImageOtherLayers.begin();
                std::advance(it, idx - 1);
                ri = &it->second;
            }
            cv::Mat rangeImg(ri->rows(), ri->cols(), CV_16UC1, ri->data());

            // Remap:
            cv::remap(rangeImg, outRangeImg, m1, m2, cv::INTER_NEAREST);
            // Overwrite:
            outRangeImg.copyTo(rangeImg);
        }

        cameraParams.dist.fill(0);
        for (int r = 0; r < 3; r++)
            for (int c = 0; c < 3; c++)
                cameraParams.intrinsicParams(r, c) =
                    newIntrinsics.at<double>(r, c);
    }

    // RGB image:
    if (hasIntensityImage)
    {
        mrpt::img::CImage newIntImg;
        intensityImage.undistort(newIntImg, cameraParamsIntensity);

        intensityImage = std::move(newIntImg);
        cameraParamsIntensity.dist.fill(0);
    }

#else
    THROW_EXCEPTION("This method requires OpenCV");
#endif
}

mrpt::img::CImage CObservation3DRangeScan::rangeImageAsImage(
    const mrpt::math::CMatrix_u16& ri, float val_min, float val_max,
    float rangeUnits, const std::optional<mrpt::img::TColormap> color)
{
#if MRPT_HAS_OPENCV
    if (val_max < 1e-4f) val_max = ri.maxCoeff() * rangeUnits;

    ASSERT_ABOVE_(val_max, val_min);

    const float range_inv = rangeUnits / (val_max - val_min);

    ASSERT_ABOVE_(ri.cols(), 0);
    ASSERT_ABOVE_(ri.rows(), 0);

    mrpt::img::CImage img;
    const int cols = ri.cols(), rows = ri.rows();

    const auto col = color.value_or(mrpt::img::TColormap::cmGRAYSCALE);

    const bool is_gray = (col == mrpt::img::TColormap::cmGRAYSCALE);

    img.resize(cols, rows, is_gray ? mrpt::img::CH_GRAY : mrpt::img::CH_RGB);

    for (int r = 0; r < rows; r++)
    {
        for (int c = 0; c < cols; c++)
        {
            // Normalized value in the range [0,1]:
            const float val_01 = (ri.coeff(r, c) - val_min) * range_inv;
            if (is_gray)
            {
                img.setPixel(c, r, static_cast<uint8_t>(val_01 * 255));
            }
            else
            {
                float R, G, B;
                mrpt::img::colormap(col, val_01, R, G, B);

                img.setPixel(
                    c, r,
                    mrpt::img::TColor(
                        static_cast<uint8_t>(R * 255),
                        static_cast<uint8_t>(G * 255),
                        static_cast<uint8_t>(B * 255)));
            }
        }
    }

    return img;
#else
    THROW_EXCEPTION("This method requires OpenCV");
#endif
}

mrpt::img::CImage CObservation3DRangeScan::rangeImage_getAsImage(
    const std::optional<mrpt::img::TColormap> color,
    const std::optional<float> normMinRange,
    const std::optional<float> normMaxRange,
    const std::optional<std::string> additionalLayerName) const
{
    ASSERT_(this->hasRangeImage);
    const mrpt::math::CMatrix_u16* ri =
        (!additionalLayerName || additionalLayerName->empty())
            ? &rangeImage
            : &rangeImageOtherLayers.at(*additionalLayerName);

    const float val_min = normMinRange.value_or(.0f);
    const float val_max = normMaxRange.value_or(this->maxRange);
    ASSERT_ABOVE_(val_max, val_min);

    return rangeImageAsImage(*ri, val_min, val_max, rangeUnits, color);
}