CKinect.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2018, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */
#ifndef mrpt_CKinect_H
#define mrpt_CKinect_H

#include <mrpt/hwdrivers/CGenericSensor.h>
#include <mrpt/obs/CObservation3DRangeScan.h>
#include <mrpt/obs/CObservationIMU.h>
#include <mrpt/typemeta/TEnumType.h>
#include <mrpt/gui/CDisplayWindow.h>

// MRPT implements a common interface to Kinect disregarding the
//  actual underlying library. These macros defined in "mrpt/config.h"
//  let us know which library is actually used:
//   - [DEPRECATED AS OF MRPT 1.3.0] MRPT_HAS_KINECT_CL_NUI     = 0 or 1
//   - MRPT_HAS_KINECT_FREENECT   = 0 or 1

// Depth of Kinect ranges:
#if MRPT_HAS_KINECT_FREENECT
#define MRPT_KINECT_DEPTH_10BIT
#define KINECT_RANGES_TABLE_LEN 1024
#define KINECT_RANGES_TABLE_MASK 0x03FF
#else  //  MRPT_HAS_KINECT_CL_NUI or none:
#define MRPT_KINECT_DEPTH_11BIT
#define KINECT_RANGES_TABLE_LEN 2048
#define KINECT_RANGES_TABLE_MASK 0x07FF
#endif

namespace mrpt::hwdrivers
{
/** A class for grabing "range images", intensity images (either RGB or IR) and
 *other information from an Xbox Kinect sensor.
 * To use Kinect for Windows or ASUS/Primesense RGBD cameras, use the class
 *COpenNI2.
 *
 *  <h2>Configuration and usage:</h2> <hr>
 * Data is returned as observations of type mrpt::obs::CObservation3DRangeScan
 *(and mrpt::obs::CObservationIMU for accelerometers data).
 *  See those classes for documentation on their fields.
 *
 * As with any other CGenericSensor class, the normal sequence of methods to be
 *called is:
 *   - CGenericSensor::loadConfig() - Or calls to the individual setXXX() to
 *configure the sensor parameters.
 *   - CKinect::initialize() - to start the communication with the sensor.
 *   - call CKinect::getNextObservation() for getting the data.
 *
 * <h2>Calibration parameters</h2><hr>
 *  For an accurate transformation of depth images to 3D points, you'll have to
 *calibrate your Kinect, and supply
 *   the following <b>threee pieces of information</b> (default calibration
 *data will be used otherwise, but they'll be not optimal for all sensors!):
 *    - Camera parameters for the RGB camera. See
 *CKinect::setCameraParamsIntensity()
 *    - Camera parameters for the depth camera. See
 *CKinect::setCameraParamsDepth()
 *    - The 3D relative pose of the two cameras. See
 *CKinect::setRelativePoseIntensityWrtDepth()
 *
 *   See http://www.mrpt.org/Kinect_calibration for a procedure to calibrate
 *Kinect sensors with an interactive GUI program.
 *
 * <h2>Coordinates convention</h2><hr>
 *   The origin of coordinates is the focal point of the depth camera, with the
 *axes oriented as in the
 *   diagram shown in mrpt::obs::CObservation3DRangeScan. Notice in that
 *picture that the RGB camera is
 *   assumed to have axes as usual in computer vision, which differ from those
 *for the depth camera.
 *
 *   The X,Y,Z axes used to report the data from accelerometers coincide with
 *those of the depth camera
 *    (e.g. the camera standing on a table would have an ACC_Z=-9.8m/s2).
 *
 *   Notice however that, for consistency with stereo cameras, when loading the
 *calibration parameters from
 *    a configuration file, the left-to-right pose increment is expected as if
 *both RGB & IR cameras had
 *    their +Z axes pointing forward, +X to the right, +Y downwards (just like
 *it's the standard in stereo cameras
 *    and in computer vision literature). In other words: the pose stored in
 *this class uses a different
 *    axes convention for the depth camera than in a stereo camera, so when a
 *pose L2R is loaded from a calibration file
 *    it's actually converted like:
 *
 *      L2R(this class convention) = CPose3D(0,0,0,-90deg,0deg,-90deg) (+)
 *L2R(in the config file)
 *
 *
 * <h2>Some general comments</h2><hr>
 *      - Depth is grabbed in 10bit depth, and a range N it's converted to
 *meters
 *as: range(m) = 0.1236 * tan(N/2842.5 + 1.1863)
 *      - This sensor can be also used from within rawlog-grabber to grab
 *datasets
 *within a robot with more sensors.
 *      - There is no built-in threading support, so if you use this class
 *manually
 *(not with-in rawlog-grabber),
 *          the ideal would be to create a thread and continuously request data
 *from
 *that thread (see mrpt::system::createThread ).
 *      - The intensity channel default to the RGB images, but it can be changed
 *with setVideoChannel() to read the IR camera images (useful for calibrating).
 *      - There is a built-in support for an optional preview of the data on a
 *window, so you don't need to even worry on creating a window to show them.
 *      - This class relies on an embedded version of libfreenect (you do NOT
 *need
 *to install it in your system). Thanks guys for the great job!
 *
 * <h2>Converting to 3D point cloud </h2><hr>
 *   You can convert the 3D observation into a 3D point cloud with this piece
 *of code:
 *
 * \code
 * mrpt::obs::CObservation3DRangeScan  obs3D;
 * mrpt::maps::CColouredPointsMap       pntsMap;
 * pntsMap.colorScheme.scheme = CColouredPointsMap::cmFromIntensityImage;
 * pntsMap.loadFromRangeScan(obs3D);
 * \endcode
 *
 *   Then the point cloud mrpt::maps::CColouredPointsMap can be converted into
 *an OpenGL object for
 *    rendering with mrpt::maps::CMetricMap::getAs3DObject() or alternatively
 *with:
 *
 *  \code
 *    mrpt::opengl::CPointCloudColoured::Ptr gl_points =
 *mrpt::make_aligned_shared<mrpt::opengl::CPointCloudColoured>();
 *    gl_points->loadFromPointsMap(&pntsMap);
 *  \endcode
 *
 *
 * <h2>Raw depth to range conversion</h2><hr>
 *  At construction, this class builds an internal array for converting raw 10
 *or 11bit depths into ranges in meters.
 *   Users can read that array or modify it (if you have a better calibration,
 *for example) by calling CKinect::getRawDepth2RangeConversion().
 *   If you replace it, remember to set the first and last entries (index 0 and
 *KINECT_RANGES_TABLE_LEN-1) to zero, to indicate that those are invalid
 *ranges.
 *
 *  <table width="100%" >
 *  <tr>
 *  <td align="center" >
 *   <img src="kinect_depth2range_10bit.png" > <br>
 *    R(d) = k3 * tan(d/k2 + k1); <br>
 *    k1 = 1.1863,  k2 = 2842.5, k3 = 0.1236 <br>
 *  </td>
 *  <td align="center" >
 *  </td>
 *  </tr>
 *  </table>
 *
 *
 * <h2>Platform-specific comments</h2><hr>
 *   For more details, refer to <a href="http://openkinect.org/wiki/Main_Page"
 *>libfreenect</a> documentation:
 *      - Linux: You'll need root privileges to access Kinect. Or, install
 *<code>
 *MRPT/scripts/51-kinect.rules </code> in <code>/etc/udev/rules.d/</code> to
 *allow access to all users.
 *      - Windows:
 *          - Since MRPT 0.9.4 you'll only need to install <a
 *href="http://sourceforge.net/projects/libusb-win32/files/libusb-win32-releases/"
 *>libusb-win32</a>: download and extract the latest
 *libusb-win32-bin-x.x.x.x.zip
 *          - To install the drivers, read this:
 *http://openkinect.org/wiki/Getting_Started#Windows
 *      - MacOS: (write me!)
 *
 *
 * <h2>Format of parameters for loading from a .ini file</h2><hr>
 *
 *  \code
 *  PARAMETERS IN THE ".INI"-LIKE CONFIGURATION STRINGS:
 * -------------------------------------------------------
 *   [supplied_section_name]
 *    sensorLabel     = KINECT       // A text description
 *    preview_window  = false        // Show a window with a preview of the
 *grabbed data in real-time
 *
 *    device_number   = 0           // Device index to open (0:first Kinect,
 *1:second Kinect,...)
 *
 *    grab_image      = true        // Grab the RGB image channel?
 *(Default=true)
 *    grab_depth      = true        // Grab the depth channel? (Default=true)
 *    grab_3D_points  = true        // Grab the 3D point cloud? (Default=true)
 *If disabled, points can be generated later on.
 *    grab_IMU        = true        // Grab the accelerometers? (Default=true)
 *
 *    video_channel   = VIDEO_CHANNEL_RGB // Optional. Can be:
 *VIDEO_CHANNEL_RGB (default) or VIDEO_CHANNEL_IR
 *
 *    pose_x=0  // Camera position in the robot (meters)
 *    pose_y=0
 *    pose_z=0
 *    pose_yaw=0    // Angles in degrees
 *    pose_pitch=0
 *    pose_roll=0
 *
 *    // Optional: Set the initial tilt angle of Kinect: upon initialization,
 *the motor is sent a command to
 *    //            rotate to this angle (in degrees). Note: You must be aware
 *of the tilt when interpreting the sensor readings.
 *    //           If not present or set to "360", no motor command will be
 *sent at start up.
 *    initial_tilt_angle = 0
 *
 *    // Kinect sensor calibration:
 *    // See http://www.mrpt.org/Kinect_and_MRPT
 *
 *    // Left/Depth camera
 *    [supplied_section_name_LEFT]
 *    rawlog-grabber-ignore = true // Instructs rawlog-grabber to ignore this
 *section (it is not a separate device!)
 *
 *    resolution = [640 488]
 *    cx         = 314.649173
 *    cy         = 240.160459
 *    fx         = 572.882768
 *    fy         = 542.739980
 *    dist       = [-4.747169e-03 -4.357976e-03 0.000000e+00 0.000000e+00
 *0.000000e+00]    // The order is: [K1 K2 T1 T2 K3]
 *
 *    // Right/RGB camera
 *    [supplied_section_name_RIGHT]
 *    rawlog-grabber-ignore = true // Instructs rawlog-grabber to ignore this
 *section (it is not a separate device!)
 *
 *    resolution = [640 480]
 *    cx         = 322.515987
 *    cy         = 259.055966
 *    fx         = 521.179233
 *    fy         = 493.033034
 *    dist       = [5.858325e-02 3.856792e-02 0.000000e+00 0.000000e+00
 *0.000000e+00]    // The order is: [K1 K2 T1 T2 K3]
 *
 *    // Relative pose of the right camera wrt to the left camera:
 *    // This assumes that both camera frames are such that +Z points
 *    // forwards, and +X and +Y to the right and downwards.
 *    // For the actual coordinates employed in 3D observations, see figure in
 *mrpt::obs::CObservation3DRangeScan
 *    [supplied_section_name_LEFT2RIGHT_POSE]
 *    rawlog-grabber-ignore = true // Instructs rawlog-grabber to ignore this
 *section (it is not a separate device!)
 *
 *    pose_quaternion      = [0.025575 -0.000609 -0.001462 0.999987 0.002038
 *0.004335 -0.001693]
 *
 *  \endcode
 *
 *  More references to read:
 *      - http://openkinect.org/wiki/Imaging_Information
 *      - http://nicolas.burrus.name/index.php/Research/KinectCalibration
 * \ingroup mrpt_hwdrivers_grp
 */
class CKinect : public mrpt::hwdrivers::CGenericSensor
{
    DEFINE_GENERIC_SENSOR(CKinect)

   public:
    /** A type for an array that converts raw depth to ranges in meters. */
    using TDepth2RangeArray = float[KINECT_RANGES_TABLE_LEN];

    /** RGB or IR video channel identifiers \sa setVideoChannel */
    enum TVideoChannel
    {
        VIDEO_CHANNEL_RGB = 0,
        VIDEO_CHANNEL_IR
    };

    /** Default ctor */
    CKinect();
    /** Default ctor */
    ~CKinect();

    /** Initializes the 3D camera - should be invoked after calling loadConfig()
     * or setting the different parameters with the set*() methods.
     *  \exception This method must throw an exception with a descriptive
     * message if some critical error is found.
     */
    virtual void initialize();

    /** To be called  at a high rate (>XX Hz), this method populates the
     * internal buffer of received observations.
     *  This method is mainly intended for usage within rawlog-grabber or
     * similar programs.
     *  For an alternative, see getNextObservation()
     *  \exception This method must throw an exception with a descriptive
     * message if some critical error is found.
     * \sa getNextObservation
     */
    virtual void doProcess();

    /** The main data retrieving function, to be called after calling
     * loadConfig() and initialize().
     *  \param out_obs The output retrieved observation (only if
     * there_is_obs=true).
     *  \param there_is_obs If set to false, there was no new observation.
     *  \param hardware_error True on hardware/comms error.
     *
     * \sa doProcess
     */
    void getNextObservation(
        mrpt::obs::CObservation3DRangeScan& out_obs, bool& there_is_obs,
        bool& hardware_error);

    /** \overload
     * \note This method also grabs data from the accelerometers, returning
     * them in out_obs_imu
     */
    void getNextObservation(
        mrpt::obs::CObservation3DRangeScan& out_obs,
        mrpt::obs::CObservationIMU& out_obs_imu, bool& there_is_obs,
        bool& hardware_error);

    /**  Set the path where to save off-rawlog image files (this class DOES take
     * into account this path).
     *  An  empty string (the default value at construction) means to save
     * images embedded in the rawlog, instead of on separate files.
     * \exception std::exception If the directory doesn't exists and cannot be
     * created.
     */
    virtual void setPathForExternalImages(const std::string& directory);

    /** @name Sensor parameters (alternative to \a loadConfig ) and manual
       control
        @{ */

    /** Try to open the camera (set all the parameters before calling this) -
     * users may also call initialize(), which in turn calls this method.
     *  Raises an exception upon error.
     * \exception std::exception A textual description of the error.
     */
    void open();

    /** Whether there is a working connection to the sensor */
    bool isOpen() const;

    /** Close the Connection to the sensor (not need to call it manually unless
     * desired for some reason,
     * since it's called at destructor) */
    void close();

    /** Changes the video channel to open (RGB or IR) - you can call this method
       before start grabbing or in the middle of streaming and the video source
       will change on the fly.
        Default is RGB channel. */
    void setVideoChannel(const TVideoChannel vch);
    /** Return the current video channel (RGB or IR) \sa setVideoChannel */
    inline TVideoChannel getVideoChannel() const { return m_video_channel; }
    /** Set the sensor index to open (if there're several sensors attached to
     * the computer); default=0 -> the first one. */
    inline void setDeviceIndexToOpen(int index)
    {
        m_user_device_number = index;
    }
    inline int getDeviceIndexToOpen() const { return m_user_device_number; }
    /** Change tilt angle \note Sensor must be open first. */
    void setTiltAngleDegrees(double angle);
    double getTiltAngleDegrees();

    /** Default: disabled */
    inline void enablePreviewRGB(bool enable = true)
    {
        m_preview_window = enable;
    }
    inline void disablePreviewRGB() { m_preview_window = false; }
    inline bool isPreviewRGBEnabled() const { return m_preview_window; }
    /** If preview is enabled, show only one image out of N (default: 1=show
     * all) */
    inline void setPreviewDecimation(size_t decimation_factor)
    {
        m_preview_window_decimation = decimation_factor;
    }
    inline size_t getPreviewDecimation() const
    {
        return m_preview_window_decimation;
    }

    /** Get the maximum range (meters) that can be read in the observation field
     * "rangeImage" */
    inline double getMaxRange() const { return m_maxRange; }
    /** Get the row count in the camera images, loaded automatically upon camera
     * open(). */
    inline size_t rows() const { return m_cameraParamsRGB.nrows; }
    /** Get the col count in the camera images, loaded automatically upon camera
     * open(). */
    inline size_t cols() const { return m_cameraParamsRGB.ncols; }
    /** Get a const reference to the depth camera calibration parameters */
    inline const mrpt::img::TCamera& getCameraParamsIntensity() const
    {
        return m_cameraParamsRGB;
    }
    inline void setCameraParamsIntensity(const mrpt::img::TCamera& p)
    {
        m_cameraParamsRGB = p;
    }

    /** Get a const reference to the depth camera calibration parameters */
    inline const mrpt::img::TCamera& getCameraParamsDepth() const
    {
        return m_cameraParamsDepth;
    }
    inline void setCameraParamsDepth(const mrpt::img::TCamera& p)
    {
        m_cameraParamsDepth = p;
    }

    /** Set the pose of the intensity camera wrt the depth camera \sa See
     * mrpt::obs::CObservation3DRangeScan for a 3D diagram of this pose */
    inline void setRelativePoseIntensityWrtDepth(const mrpt::poses::CPose3D& p)
    {
        m_relativePoseIntensityWRTDepth = p;
    }
    inline const mrpt::poses::CPose3D& getRelativePoseIntensityWrtDepth() const
    {
        return m_relativePoseIntensityWRTDepth;
    }

    /** Get a reference to the array that convert raw depth values (10 or 11
     * bit) into ranges in meters, so it can be read or replaced by the user.
     *  If you replace it, remember to set the first and last entries (index 0
     * and KINECT_RANGES_TABLE_LEN-1) to zero, to indicate that those are
     * invalid ranges.
     */
    inline TDepth2RangeArray& getRawDepth2RangeConversion()
    {
        return m_range2meters;
    }
    inline const TDepth2RangeArray& getRawDepth2RangeConversion() const
    {
        return m_range2meters;
    }

    /** Enable/disable the grabbing of the RGB channel */
    inline void enableGrabRGB(bool enable = true) { m_grab_image = enable; }
    inline bool isGrabRGBEnabled() const { return m_grab_image; }
    /** Enable/disable the grabbing of the depth channel */
    inline void enableGrabDepth(bool enable = true) { m_grab_depth = enable; }
    inline bool isGrabDepthEnabled() const { return m_grab_depth; }
    /** Enable/disable the grabbing of the inertial data */
    inline void enableGrabAccelerometers(bool enable = true)
    {
        m_grab_IMU = enable;
    }
    inline bool isGrabAccelerometersEnabled() const { return m_grab_IMU; }
    /** Enable/disable the grabbing of the 3D point clouds */
    inline void enableGrab3DPoints(bool enable = true)
    {
        m_grab_3D_points = enable;
    }
    inline bool isGrab3DPointsEnabled() const { return m_grab_3D_points; }
    /** @} */

#if MRPT_HAS_KINECT_FREENECT
    // Auxiliary getters/setters (we can't declare the libfreenect callback as
    // friend since we
    //   want to avoid including the API headers here).
    inline mrpt::obs::CObservation3DRangeScan& internal_latest_obs()
    {
        return m_latest_obs;
    }
    inline volatile uint32_t& internal_tim_latest_depth()
    {
        return m_tim_latest_depth;
    }
    inline volatile uint32_t& internal_tim_latest_rgb()
    {
        return m_tim_latest_rgb;
    }
    inline std::mutex& internal_latest_obs_cs() { return m_latest_obs_cs; }
#endif

   protected:
    /** See the class documentation at the top for expected parameters */
    virtual void loadConfig_sensorSpecific(
        const mrpt::config::CConfigFileBase& configSource,
        const std::string& section);

    mrpt::poses::CPose3D m_sensorPoseOnRobot;

    /** Show preview window while grabbing */
    bool m_preview_window;
    /** If preview is enabled, only show 1 out of N images. */
    size_t m_preview_window_decimation;
    size_t m_preview_decim_counter_range, m_preview_decim_counter_rgb;
    mrpt::gui::CDisplayWindow::Ptr m_win_range, m_win_int;

#if MRPT_HAS_KINECT_FREENECT
    /** The "freenect_context", or nullptr if closed */
    void* m_f_ctx;
    /** The "freenect_device", or nullptr if closed */
    void* m_f_dev;

    // Data fields for use with the callback function:
    mrpt::obs::CObservation3DRangeScan m_latest_obs;
    volatile uint32_t m_tim_latest_depth, m_tim_latest_rgb;  // 0 = not updated
    std::mutex m_latest_obs_cs;
#endif

    /** Params for the RGB camera */
    mrpt::img::TCamera m_cameraParamsRGB;
    /** Params for the Depth camera */
    mrpt::img::TCamera m_cameraParamsDepth;
    /** See mrpt::obs::CObservation3DRangeScan for a diagram of this pose */
    mrpt::poses::CPose3D m_relativePoseIntensityWRTDepth;

    /** Set Kinect tilt to an initial deegre (it should be take in account in
     * the sensor pose by the user) */
    int m_initial_tilt_angle;

    /** Sensor max range (meters) */
    double m_maxRange;

    /** Number of device to open (0:first,...) */
    int m_user_device_number;

    /** Default: all true */
    bool m_grab_image, m_grab_depth, m_grab_3D_points, m_grab_IMU;

    /** The video channel to open: RGB or IR */
    TVideoChannel m_video_channel;

   private:
    /** Temporary buffers for image grabbing. */
    std::vector<uint8_t> m_buf_depth, m_buf_rgb;
    /** The table raw depth -> range in meters */
    TDepth2RangeArray m_range2meters;

    /** Compute m_range2meters at construction */
    void calculate_range2meters();

};  // End of class
}
MRPT_ENUM_TYPE_BEGIN(mrpt::hwdrivers::CKinect::TVideoChannel)
using namespace mrpt::hwdrivers;
MRPT_FILL_ENUM_MEMBER(CKinect, VIDEO_CHANNEL_RGB);
MRPT_FILL_ENUM_MEMBER(CKinect, VIDEO_CHANNEL_IR);
MRPT_ENUM_TYPE_END()

#endif