CKinect.h

Go to the documentation of this file.

/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          http://www.mrpt.org/                             |
   |                                                                           |
   | Copyright (c) 2005-2014, 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/slam/CObservation3DRangeScan.h>
#include <mrpt/slam/CObservationIMU.h>
#include <mrpt/utils/TEnumType.h>
#include <mrpt/gui/CDisplayWindow.h>

#include <mrpt/hwdrivers/link_pragmas.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:
//   - 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
{
        namespace 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::slam::CObservation3DRangeScan (and mrpt::slam::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::slam::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::slam::CObservation3DRangeScan  obs3D;
                  * mrpt::slam::CColouredPointsMap       pntsMap;
                  * pntsMap.colorScheme.scheme = CColouredPointsMap::cmFromIntensityImage;
                  * pntsMap.loadFromRangeScan(obs3D);
                  * \endcode
                  *
                  *   Then the point cloud mrpt::slam::CColouredPointsMap can be converted into an OpenGL object for
                  *    rendering with mrpt::slam::CMetricMap::getAs3DObject() or alternatively with:
                  *
                  *  \code
                  *    mrpt::opengl::CPointCloudColouredPtr gl_points = mrpt::opengl::CPointCloudColoured::Create();
                  *    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::slam::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 HWDRIVERS_IMPEXP  CKinect : public mrpt::hwdrivers::CGenericSensor
                {
                        DEFINE_GENERIC_SENSOR(CKinect)

                public:
                        typedef float TDepth2RangeArray[KINECT_RANGES_TABLE_LEN]; //!< A typedef for an array that converts raw depth to ranges in meters.

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

                        CKinect();       //!< Default ctor
                        ~CKinect();      //!< Default ctor

                        /** 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::slam::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::slam::CObservation3DRangeScan &out_obs,
                                mrpt::slam::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();

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

                        /** Close the conection 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 getRowCount() const { return m_cameraParamsRGB.nrows; }
                        /** Get the col count in the camera images, loaded automatically upon camera open(). */
                        inline size_t getColCount() const { return m_cameraParamsRGB.ncols; }

                        /** Get a const reference to the depth camera calibration parameters */
                        inline const mrpt::utils::TCamera  & getCameraParamsIntensity() const { return m_cameraParamsRGB; }
                        inline void setCameraParamsIntensity(const mrpt::utils::TCamera  &p) { m_cameraParamsRGB=p; }

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

                        /** Set the pose of the intensity camera wrt the depth camera \sa See mrpt::slam::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::slam::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 mrpt::synch::CCriticalSection & 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::utils::CConfigFileBase &configSource,
                                const std::string                       &section );

                        mrpt::poses::CPose3D    m_sensorPoseOnRobot;

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

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

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

#if MRPT_HAS_KINECT_CL_NUI
                        void *m_clnui_cam;   //!< The "CLNUICamera" or NULL if closed
                        void *m_clnui_motor; //!< The "CLNUIMotor" or NULL if closed
#endif

                        mrpt::utils::TCamera    m_cameraParamsRGB;  //!< Params for the RGB camera
                        mrpt::utils::TCamera    m_cameraParamsDepth;  //!< Params for the Depth camera
                        mrpt::poses::CPose3D    m_relativePoseIntensityWRTDepth; //!< See mrpt::slam::CObservation3DRangeScan for a diagram of this pose

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

                        double  m_maxRange; //!< Sensor max range (meters)

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

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

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

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

                        void calculate_range2meters(); //!< Compute m_range2meters at construction

                };      // End of class
        } // End of NS

        // Specializations MUST occur at the same namespace:
        namespace utils
        {
                template <>
                struct TEnumTypeFiller<hwdrivers::CKinect::TVideoChannel>
                {
                        typedef hwdrivers::CKinect::TVideoChannel enum_t;
                        static void fill(bimap<enum_t,std::string>  &m_map)
                        {
                                m_map.insert(hwdrivers::CKinect::VIDEO_CHANNEL_RGB, "VIDEO_CHANNEL_RGB");
                                m_map.insert(hwdrivers::CKinect::VIDEO_CHANNEL_IR,  "VIDEO_CHANNEL_IR");
                        }
                };
        } // End of namespace

} // End of NS


#endif