libvisp_tracker/tracker.cpp

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#include <stdexcept>

#include <boost/filesystem/fstream.hpp>
#include <boost/format.hpp>
#include <boost/scope_exit.hpp>
#include <boost/version.hpp>

#include <dynamic_reconfigure/server.h>
#include <geometry_msgs/PoseWithCovarianceStamped.h>
#include <image_proc/advertisement_checker.h>
#include <image_transport/image_transport.h>
#include <ros/param.h>
#include <ros/ros.h>
#include <ros/transport_hints.h>
#include <sensor_msgs/Image.h>
#include <std_msgs/String.h>
#include <tf/transform_broadcaster.h>

#include <boost/bind.hpp>
#include <visp3/core/vpExponentialMap.h>
#include <visp3/core/vpImage.h>
#include <visp3/core/vpImageConvert.h>
#include <visp3/core/vpCameraParameters.h>

#include "tracker.hh"

#include "conversion.hh"
#include "callbacks.hh"
#include "file.hh"
#include "names.hh"

// TODO:
// - add a topic allowing to suggest an estimation of the cMo
// - handle automatic reset when tracking is lost.

namespace visp_tracker
{
  bool
  Tracker::initCallback(visp_tracker::Init::Request& req,
                        visp_tracker::Init::Response& res)
  {
    ROS_INFO("Initialization request received.");

    res.initialization_succeed = false;

    // If something goes wrong, rollback all changes.
    BOOST_SCOPE_EXIT((&res)(&tracker_)(&state_)
                     (&lastTrackedImage_)(&trackerType_))
    {
      if(!res.initialization_succeed)
      {
        tracker_.resetTracker();
        state_ = WAITING_FOR_INITIALIZATION;
        lastTrackedImage_ = 0;

      }
    } BOOST_SCOPE_EXIT_END;

    std::string fullModelPath;
    boost::filesystem::ofstream modelStream;

    // Load model from parameter.
    if (!makeModelFile(modelStream, fullModelPath))
      return true;

    tracker_.resetTracker();

    // Common parameters
    convertInitRequestToVpMbTracker(req, tracker_);

    if(trackerType_!="klt"){ // for mbt and hybrid
      convertInitRequestToVpMe(req, tracker_, movingEdge_);
    }

    if(trackerType_!="mbt"){ // for klt and hybrid
      convertInitRequestToVpKltOpencv(req, tracker_, kltTracker_);
    }

    if(trackerType_=="mbt+klt"){ // Hybrid Tracker reconfigure
      visp_tracker::ModelBasedSettingsConfig config;
      convertVpMbTrackerToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsConfig>(tracker_, config);
      reconfigureSrv_->updateConfig(config);
      convertVpMeToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsConfig>(movingEdge_, tracker_, config);
      reconfigureSrv_->updateConfig(config);
      convertVpKltOpencvToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsConfig>(kltTracker_, tracker_, config);
      reconfigureSrv_->updateConfig(config);
    }
    else if(trackerType_=="mbt"){ // Edge Tracker reconfigure
      visp_tracker::ModelBasedSettingsEdgeConfig config;
      convertVpMbTrackerToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsEdgeConfig>(tracker_, config);
      reconfigureEdgeSrv_->updateConfig(config);
      convertVpMeToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsEdgeConfig>(movingEdge_, tracker_, config);
      reconfigureEdgeSrv_->updateConfig(config);
    }
    else{ // KLT Tracker reconfigure
      visp_tracker::ModelBasedSettingsKltConfig config;
      convertVpMbTrackerToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsKltConfig>(tracker_, config);
      reconfigureKltSrv_->updateConfig(config);
      convertVpKltOpencvToModelBasedSettingsConfig<visp_tracker::ModelBasedSettingsKltConfig>(kltTracker_, tracker_, config);
      reconfigureKltSrv_->updateConfig(config);
    }

    state_ = WAITING_FOR_INITIALIZATION;
    lastTrackedImage_ = 0;

    // Load the model.
    try
    {
      ROS_DEBUG_STREAM("Trying to load the model Tracker: " << fullModelPath);
      tracker_.loadModel(fullModelPath.c_str());
      modelStream.close();
    }
    catch(...)
    {
      ROS_ERROR_STREAM("Failed to load the model: " << fullModelPath);
      return true;
    }
    ROS_DEBUG("Model has been successfully loaded.");

    // Load the initial cMo.
    transformToVpHomogeneousMatrix(cMo_, req.initial_cMo);

    // Enable covariance matrix.
    tracker_.setCovarianceComputation(true);

    // Try to initialize the tracker.
    ROS_INFO_STREAM("Initializing tracker with cMo:\n" << cMo_);
    try
    {
      // Bug between setPose() and initFromPose() not present here due to previous call to resetTracker()
      tracker_.initFromPose(image_, cMo_);
      ROS_INFO("Tracker successfully initialized.");

      //movingEdge.print();
      ROS_INFO_STREAM(convertVpMbTrackerToRosMessage(tracker_));
      // - Moving edges.
      if(trackerType_!="klt")
        ROS_INFO_STREAM(convertVpMeToRosMessage(tracker_, movingEdge_));

      if(trackerType_!="mbt")
        ROS_INFO_STREAM(convertVpKltOpencvToRosMessage(tracker_,kltTracker_));
    }
    catch(const std::string& str)
    {
      ROS_ERROR_STREAM("Tracker initialization has failed: " << str);
    }

    // Initialization is valid.
    res.initialization_succeed = true;
    state_ = TRACKING;
    return true;
  }

  void
  Tracker::updateMovingEdgeSites(visp_tracker::MovingEdgeSitesPtr sites)
  {
    if (!sites)
      return;

    std::list<vpMbtDistanceLine*> linesList;

    if(trackerType_!="klt") { // For mbt and hybrid
      tracker_.getLline(linesList, 0);

      std::list<vpMbtDistanceLine*>::iterator linesIterator = linesList.begin();

      bool noVisibleLine = true;
      for (; linesIterator != linesList.end(); ++linesIterator)
      {
        vpMbtDistanceLine* line = *linesIterator;

#if VISP_VERSION_INT >= VP_VERSION_INT(3,0,0) // ViSP >= 3.0.0
        if (line && line->isVisible() && ! line->meline.empty())
#else
        if (line && line->isVisible() && line->meline)
#endif
        {
#if VISP_VERSION_INT >= VP_VERSION_INT(3,0,0) // ViSP >= 3.0.0
          for(unsigned int a = 0 ; a < line->meline.size() ; a++)
          {
            if(line->meline[a] != NULL) {
              std::list<vpMeSite>::const_iterator sitesIterator = line->meline[a]->getMeList().begin();
              if (line->meline[a]->getMeList().empty())
                ROS_DEBUG_THROTTLE(10, "no moving edge for a line");
              for (; sitesIterator != line->meline[a]->getMeList().end(); ++sitesIterator)
              {
#elif VISP_VERSION_INT >= VP_VERSION_INT(2,10,0) // ViSP >= 2.10.0
          std::list<vpMeSite>::const_iterator sitesIterator = line->meline->getMeList().begin();
          if (line->meline->getMeList().empty())
            ROS_DEBUG_THROTTLE(10, "no moving edge for a line");
          for (; sitesIterator != line->meline->getMeList().end(); ++sitesIterator)
          {
#else
          std::list<vpMeSite>::const_iterator sitesIterator = line->meline->list.begin();
          if (line->meline->list.empty())
            ROS_DEBUG_THROTTLE(10, "no moving edge for a line");
          for (; sitesIterator != line->meline->list.end(); ++sitesIterator)
          {
#endif
            visp_tracker::MovingEdgeSite movingEdgeSite;
            movingEdgeSite.x = sitesIterator->ifloat;
            movingEdgeSite.y = sitesIterator->jfloat;
#if VISP_VERSION_INT < VP_VERSION_INT(2,10,0) // ViSP < 2.10.0
            movingEdgeSite.suppress = sitesIterator->suppress;
#endif
            sites->moving_edge_sites.push_back (movingEdgeSite);
          }
          noVisibleLine = false;
        }
#if VISP_VERSION_INT >= VP_VERSION_INT(3,0,0) // ViSP >= 3.0.0
      }
    }
#endif
  }
  if (noVisibleLine)
  ROS_DEBUG_THROTTLE(10, "no distance lines");
}
}

void
Tracker::updateKltPoints(visp_tracker::KltPointsPtr klt)
{
  if (!klt)
    return;

#if VISP_VERSION_INT < VP_VERSION_INT(2,10,0) // ViSP < 2.10.0
  vpMbHiddenFaces<vpMbtKltPolygon> *poly_lst;
  std::map<int, vpImagePoint> *map_klt;

  if(trackerType_!="mbt") { // For klt and hybrid
    poly_lst = &dynamic_cast<vpMbKltTracker*>(tracker_)->getFaces();

    for(unsigned int i = 0 ; i < poly_lst->size() ; i++)
    {
      if((*poly_lst)[i])
      {
        map_klt = &((*poly_lst)[i]->getCurrentPoints());

        if(map_klt->size() > 3)
        {
          for (std::map<int, vpImagePoint>::iterator it=map_klt->begin(); it!=map_klt->end(); ++it)
          {
            visp_tracker::KltPoint kltPoint;
            kltPoint.id = it->first;
            kltPoint.i = it->second.get_i();
            kltPoint.j = it->second.get_j();
            klt->klt_points_positions.push_back (kltPoint);
          }
        }
      }
    }
  }
#else // ViSP >= 2.10.0
  std::list<vpMbtDistanceKltPoints*> poly_lst;
  std::map<int, vpImagePoint> *map_klt;

  if(trackerType_!="mbt") { // For klt and hybrid
    poly_lst = tracker_.getFeaturesKlt();

    for(std::list<vpMbtDistanceKltPoints*>::const_iterator it=poly_lst.begin(); it!=poly_lst.end(); ++it){
      map_klt = &((*it)->getCurrentPoints());

      if((*it)->polygon->isVisible()){
        if(map_klt->size() > 3)
        {
          for (std::map<int, vpImagePoint>::iterator it=map_klt->begin(); it!=map_klt->end(); ++it)
          {
            visp_tracker::KltPoint kltPoint;
            kltPoint.id = it->first;
            kltPoint.i = it->second.get_i();
            kltPoint.j = it->second.get_j();
            klt->klt_points_positions.push_back (kltPoint);
          }
        }
      }
    }
  }
#endif
}

void Tracker::checkInputs()
{
  ros::V_string topics;
  topics.push_back(rectifiedImageTopic_);
  checkInputs_.start(topics, 60.0);
}

Tracker::Tracker(ros::NodeHandle& nh,
                 ros::NodeHandle& privateNh,
                 volatile bool& exiting,
                 unsigned queueSize)
  : exiting_ (exiting),
    queueSize_(queueSize),
    nodeHandle_(nh),
    nodeHandlePrivate_(privateNh),
    imageTransport_(nodeHandle_),
    state_(WAITING_FOR_INITIALIZATION),
    image_(),
    cameraPrefix_(),
    rectifiedImageTopic_(),
    cameraInfoTopic_(),
    modelPath_(),
    cameraSubscriber_(),
    mutex_ (),
    //reconfigureSrv_(mutex_, nodeHandlePrivate_),
    reconfigureSrv_(NULL),
    reconfigureKltSrv_(NULL),
    reconfigureEdgeSrv_(NULL),
    resultPublisher_(),
    transformationPublisher_(),
    movingEdgeSitesPublisher_(),
    kltPointsPublisher_(),
    initService_(),
    header_(),
    info_(),
    kltTracker_(),
    movingEdge_(),
    cameraParameters_(),
    lastTrackedImage_(),
    checkInputs_(nodeHandle_, ros::this_node::getName()),
    cMo_ (),
    listener_ (),
    worldFrameId_ (),
    compensateRobotMotion_ (false),
    transformBroadcaster_ (),
    childFrameId_ (),
    objectPositionHintSubscriber_ (),
    objectPositionHint_ ()
{
  // Set cMo to identity.
  cMo_.eye();

  // Parameters.
  nodeHandlePrivate_.param<std::string>("camera_prefix", cameraPrefix_, "");
  nodeHandlePrivate_.param<std::string>("tracker_type", trackerType_, "mbt");
  if(trackerType_=="mbt")
    tracker_.setTrackerType(vpMbGenericTracker::EDGE_TRACKER);
  else if(trackerType_=="klt")
    tracker_.setTrackerType(vpMbGenericTracker::KLT_TRACKER);
  else
    tracker_.setTrackerType(vpMbGenericTracker::EDGE_TRACKER | vpMbGenericTracker::KLT_TRACKER);

  if (cameraPrefix_.empty ())
  {
    ROS_FATAL
        ("The camera_prefix parameter not set.\n"
         "Please relaunch the tracker while setting this parameter, i.e.\n"
         "$ rosrun visp_tracker tracker _camera_prefix:=/my/camera");
    ros::shutdown ();
    return;
  }
  // Create global /camera_prefix param to avoid to remap in the launch files the tracker_client and tracker_viewer nodes
  nodeHandle_.setParam("camera_prefix", cameraPrefix_);

  nodeHandle_.param<std::string>("frame_id", childFrameId_, "object_position");

  // Robot motion compensation.
  nodeHandle_.param<std::string>("world_frame_id", worldFrameId_, "/odom");
  nodeHandle_.param<bool>
      ("compensate_robot_motion", compensateRobotMotion_, false);

  // Compute topic and services names.
  rectifiedImageTopic_ =
      ros::names::resolve(cameraPrefix_ + "/image_rect");

  // Check for subscribed topics.
  checkInputs();

  // Result publisher.
  resultPublisher_ =
      nodeHandle_.advertise<geometry_msgs::PoseWithCovarianceStamped>
      (visp_tracker::object_position_covariance_topic, queueSize_);

  transformationPublisher_ =
      nodeHandle_.advertise<geometry_msgs::TransformStamped>
      (visp_tracker::object_position_topic, queueSize_);

  // Moving edge sites_ publisher.
  movingEdgeSitesPublisher_ =
      nodeHandle_.advertise<visp_tracker::MovingEdgeSites>
      (visp_tracker::moving_edge_sites_topic, queueSize_);

  // Klt_points_ publisher.
  kltPointsPublisher_ =
      nodeHandle_.advertise<visp_tracker::KltPoints>
      (visp_tracker::klt_points_topic, queueSize_);

  // Camera subscriber.
  cameraSubscriber_ =
      imageTransport_.subscribeCamera
      (rectifiedImageTopic_, queueSize_,
       bindImageCallback(image_, header_, info_));

  // Object position hint subscriber.
  typedef boost::function<
      void (const geometry_msgs::TransformStampedConstPtr&)>
      objectPositionHintCallback_t;
  objectPositionHintCallback_t callback =
      boost::bind (&Tracker::objectPositionHintCallback, this, _1);
  objectPositionHintSubscriber_ =
      nodeHandle_.subscribe<geometry_msgs::TransformStamped>
      ("object_position_hint", queueSize_, callback);

  // Dynamic reconfigure.
  if(trackerType_=="mbt+klt"){ // Hybrid Tracker reconfigure
    reconfigureSrv_ = new reconfigureSrvStruct<visp_tracker::ModelBasedSettingsConfig>::reconfigureSrv_t(mutex_, nodeHandlePrivate_);
    reconfigureSrvStruct<visp_tracker::ModelBasedSettingsConfig>::reconfigureSrv_t::CallbackType f =
        boost::bind(&reconfigureCallbackAndInitViewer,
                    boost::ref(nodeHandle_), boost::ref(tracker_),
                    boost::ref(image_), boost::ref(movingEdge_), boost::ref(kltTracker_),
                    boost::ref(mutex_), _1, _2);
    reconfigureSrv_->setCallback(f);
  }
  else if(trackerType_=="mbt"){ // Edge Tracker reconfigure
    reconfigureEdgeSrv_ = new reconfigureSrvStruct<visp_tracker::ModelBasedSettingsEdgeConfig>::reconfigureSrv_t(mutex_, nodeHandlePrivate_);
    reconfigureSrvStruct<visp_tracker::ModelBasedSettingsEdgeConfig>::reconfigureSrv_t::CallbackType f =
        boost::bind(&reconfigureEdgeCallbackAndInitViewer,
                    boost::ref(nodeHandle_), boost::ref(tracker_),
                    boost::ref(image_), boost::ref(movingEdge_),
                    boost::ref(mutex_), _1, _2);
    reconfigureEdgeSrv_->setCallback(f);
  }
  else{ // KLT Tracker reconfigure
    reconfigureKltSrv_ = new reconfigureSrvStruct<visp_tracker::ModelBasedSettingsKltConfig>::reconfigureSrv_t(mutex_, nodeHandlePrivate_);
    reconfigureSrvStruct<visp_tracker::ModelBasedSettingsKltConfig>::reconfigureSrv_t::CallbackType f =
        boost::bind(&reconfigureKltCallbackAndInitViewer,
                    boost::ref(nodeHandle_), boost::ref(tracker_),
                    boost::ref(image_), boost::ref(kltTracker_),
                    boost::ref(mutex_), _1, _2);
    reconfigureKltSrv_->setCallback(f);
  }

  // Wait for the image to be initialized.
  waitForImage();
  if (this->exiting())
    return;
  if (!image_.getWidth() || !image_.getHeight())
    throw std::runtime_error("failed to retrieve image");

  // Tracker initialization.
  initializeVpCameraFromCameraInfo(cameraParameters_, info_);

  // Double check camera parameters.
  if (cameraParameters_.get_px () == 0.
      || cameraParameters_.get_px () == 1.
      || cameraParameters_.get_py () == 0.
      || cameraParameters_.get_py () == 1.
      || cameraParameters_.get_u0 () == 0.
      || cameraParameters_.get_u0 () == 1.
      || cameraParameters_.get_v0 () == 0.
      || cameraParameters_.get_v0 () == 1.)
    ROS_WARN ("Dubious camera parameters detected.\n"
              "\n"
              "It seems that the matrix P from your camera\n"
              "calibration topics is wrong.\n"
              "The tracker will continue anyway, but you\n"
              "should double check your calibration data,\n"
              "especially if the model re-projection fails.\n"
              "\n"
              "This warning is triggered is px, py, u0 or v0\n"
              "is set to 0. or 1. (exactly).");

  tracker_.setCameraParameters(cameraParameters_);
  tracker_.setDisplayFeatures(false);

  ROS_INFO_STREAM(cameraParameters_);

  // Service declaration.
  initCallback_t initCallback =
      boost::bind(&Tracker::initCallback, this, _1, _2);

  initService_ = nodeHandle_.advertiseService
      (visp_tracker::init_service, initCallback);
}

Tracker::~Tracker()
{
  if(reconfigureSrv_ != NULL)
    delete reconfigureSrv_;

  if(reconfigureKltSrv_ != NULL)
    delete reconfigureKltSrv_;

  if(reconfigureEdgeSrv_ != NULL)
    delete reconfigureEdgeSrv_;
}

void Tracker::spin()
{
  ros::Rate loopRateTracking(100);
  tf::Transform transform;
  std_msgs::Header lastHeader;

  while (!exiting())
  {
    // When a camera sequence is played several times,
    // the seq id will decrease, in this case we want to
    // continue the tracking.
    if (header_.seq < lastHeader.seq)
      lastTrackedImage_ = 0;

    if (lastTrackedImage_ < header_.seq)
    {
      lastTrackedImage_ = header_.seq;

      // If we can estimate the camera displacement using tf,
      // we update the cMo to compensate for robot motion.
      if (compensateRobotMotion_)
        try
      {
        tf::StampedTransform stampedTransform;
        listener_.lookupTransform
            (header_.frame_id, // camera frame name
             header_.stamp,    // current image time
             header_.frame_id, // camera frame name
             lastHeader.stamp, // last processed image time
             worldFrameId_,    // frame attached to the environment
             stampedTransform
             );
        vpHomogeneousMatrix newMold;
        transformToVpHomogeneousMatrix (newMold, stampedTransform);
        cMo_ = newMold * cMo_;

        mutex_.lock();
        tracker_.setPose(image_, cMo_);
        mutex_.unlock();
      }
      catch(tf::TransformException& e)
      {
        mutex_.unlock();
      }

      // If we are lost but an estimation of the object position
      // is provided, use it to try to reinitialize the system.
      if (state_ == LOST)
      {
        // If the last received message is recent enough,
        // use it otherwise do nothing.
        if (ros::Time::now () - objectPositionHint_.header.stamp
            < ros::Duration (1.))
          transformToVpHomogeneousMatrix
              (cMo_, objectPositionHint_.transform);

        mutex_.lock();
        tracker_.setPose(image_, cMo_);
        mutex_.unlock();
      }

      // We try to track the image even if we are lost,
      // in the case the tracker recovers...
      if (state_ == TRACKING || state_ == LOST)
        try
      {
        mutex_.lock();
        // tracker_->setPose(image_, cMo_); // Removed as it is not necessary when the pose is not modified from outside.
        tracker_.track(image_);
        tracker_.getPose(cMo_);
        mutex_.unlock();
      }
      catch(...)
      {
        mutex_.unlock();
        ROS_WARN_THROTTLE(10, "tracking lost");
        state_ = LOST;
      }

      // Publish the tracking result.
      if (state_ == TRACKING)
      {
        geometry_msgs::Transform transformMsg;
        vpHomogeneousMatrixToTransform(transformMsg, cMo_);

        // Publish position.
        if (transformationPublisher_.getNumSubscribers  () > 0)
        {
          geometry_msgs::TransformStampedPtr objectPosition
              (new geometry_msgs::TransformStamped);
          objectPosition->header = header_;
          objectPosition->child_frame_id = childFrameId_;
          objectPosition->transform = transformMsg;
          transformationPublisher_.publish(objectPosition);
        }

        // Publish result.
        if (resultPublisher_.getNumSubscribers  () > 0)
        {
          geometry_msgs::PoseWithCovarianceStampedPtr result
              (new geometry_msgs::PoseWithCovarianceStamped);
          result->header = header_;
          result->pose.pose.position.x =
              transformMsg.translation.x;
          result->pose.pose.position.y =
              transformMsg.translation.y;
          result->pose.pose.position.z =
              transformMsg.translation.z;

          result->pose.pose.orientation.x =
              transformMsg.rotation.x;
          result->pose.pose.orientation.y =
              transformMsg.rotation.y;
          result->pose.pose.orientation.z =
              transformMsg.rotation.z;
          result->pose.pose.orientation.w =
              transformMsg.rotation.w;
          const vpMatrix& covariance =
              tracker_.getCovarianceMatrix();
          for (unsigned i = 0; i < covariance.getRows(); ++i)
            for (unsigned j = 0; j < covariance.getCols(); ++j)
            {
              unsigned idx = i * covariance.getCols() + j;
              if (idx >= 36)
                continue;
              result->pose.covariance[idx] = covariance[i][j];
            }
          resultPublisher_.publish(result);
        }

        // Publish moving edge sites.
        if (movingEdgeSitesPublisher_.getNumSubscribers () > 0)
        {
          visp_tracker::MovingEdgeSitesPtr sites
              (new visp_tracker::MovingEdgeSites);
          updateMovingEdgeSites(sites);
          sites->header = header_;
          movingEdgeSitesPublisher_.publish(sites);
        }
        // Publish KLT points.
        if (kltPointsPublisher_.getNumSubscribers       () > 0)
        {
          visp_tracker::KltPointsPtr klt
              (new visp_tracker::KltPoints);
          updateKltPoints(klt);
          klt->header = header_;
          kltPointsPublisher_.publish(klt);
        }

        // Publish to tf.
        transform.setOrigin
            (tf::Vector3(transformMsg.translation.x,
                         transformMsg.translation.y,
                         transformMsg.translation.z));
        transform.setRotation
            (tf::Quaternion
             (transformMsg.rotation.x,
              transformMsg.rotation.y,
              transformMsg.rotation.z,
              transformMsg.rotation.w));
        transformBroadcaster_.sendTransform
            (tf::StampedTransform
             (transform,
              header_.stamp,
              header_.frame_id,
              childFrameId_));
      }
    }

    lastHeader = header_;
    spinOnce();
    loopRateTracking.sleep();

  }
}

// Make sure that we have an image *and* associated calibration
// data.
void
Tracker::waitForImage()
{
  ros::Rate loop_rate(10);
  while (!exiting()
         && (!image_.getWidth() || !image_.getHeight())
         && (!info_ || info_->K[0] == 0.))
  {
    //ROS_INFO_THROTTLE(1, "waiting for a rectified image...");
    spinOnce();
    loop_rate.sleep();
  }
}

void
Tracker::objectPositionHintCallback
(const geometry_msgs::TransformStampedConstPtr& transform)
{
  objectPositionHint_ = *transform;
}

} // end of namespace visp_tracker.