face_detection.cpp

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/* Author: Caroline Pantofaru */



#include <stdio.h>
#include <iostream>
#include <vector>
#include <fstream>

#include <ros/ros.h>
#include <ros/console.h>
#include <boost/filesystem.hpp>
#include <boost/thread/mutex.hpp>

#include <people_msgs/PositionMeasurement.h>
#include <people_msgs/PositionMeasurementArray.h>
#include <message_filters/subscriber.h>
#include <message_filters/time_synchronizer.h>
#include <message_filters/sync_policies/exact_time.h>
#include <message_filters/sync_policies/approximate_time.h>
#include <image_transport/subscriber_filter.h>
#include "sensor_msgs/CameraInfo.h"
#include "sensor_msgs/Image.h"
#include "stereo_msgs/DisparityImage.h"
#include "sensor_msgs/image_encodings.h"
#include "cv_bridge/cv_bridge.h"
#include "tf/transform_listener.h"
#include "sensor_msgs/PointCloud.h"
#include "geometry_msgs/Point32.h"

#include "opencv/cxcore.hpp"
#include "opencv/cv.hpp"
#include "opencv/highgui.h"

#include "face_detector/faces.h"

#include "image_geometry/stereo_camera_model.h"

#include <actionlib/server/simple_action_server.h>
#include <face_detector/FaceDetectorAction.h>

using namespace std;

namespace people {

  class FaceDetector {
  public:
    // Constants
    const double BIGDIST_M;// = 1000000.0;

    // Node handle
    ros::NodeHandle nh_;

    boost::mutex connect_mutex_;
    bool use_rgbd_;

    // Subscription topics
    string image_image_;
    // Stereo
    string stereo_namespace_;
    string left_topic_;
    string disparity_topic_;
    string left_camera_info_topic_;
    string right_camera_info_topic_;
    // RGB-D
    string camera_;
    string camera_topic_;
    string depth_image_;
    string depth_topic_;
    string camera_info_topic_;
    string depth_info_topic_;
    string depth_ns_;

    // Images and conversion for both the stereo camera and rgb-d camera cases.
    image_transport::ImageTransport it_;
    image_transport::SubscriberFilter image_sub_; 
    image_transport::SubscriberFilter depth_image_sub_; 
    message_filters::Subscriber<stereo_msgs::DisparityImage> disp_image_sub_; 
    message_filters::Subscriber<sensor_msgs::CameraInfo> c1_info_sub_; 
    message_filters::Subscriber<sensor_msgs::CameraInfo> c2_info_sub_; 
    // Disparity:
    typedef message_filters::sync_policies::ExactTime<sensor_msgs::Image, stereo_msgs::DisparityImage, sensor_msgs::CameraInfo, sensor_msgs::CameraInfo> ExactDispPolicy; 
    typedef message_filters::sync_policies::ApproximateTime<sensor_msgs::Image, stereo_msgs::DisparityImage, sensor_msgs::CameraInfo, sensor_msgs::CameraInfo> ApproximateDispPolicy; 
    typedef message_filters::Synchronizer<ExactDispPolicy> ExactDispSync;
    typedef message_filters::Synchronizer<ApproximateDispPolicy> ApproximateDispSync;
    boost::shared_ptr<ExactDispSync> exact_disp_sync_;
    boost::shared_ptr<ApproximateDispSync> approximate_disp_sync_;

    // Depth:
    typedef message_filters::sync_policies::ExactTime<sensor_msgs::Image, sensor_msgs::Image, sensor_msgs::CameraInfo, sensor_msgs::CameraInfo> ExactDepthPolicy; 
    typedef message_filters::sync_policies::ApproximateTime<sensor_msgs::Image, sensor_msgs::Image, sensor_msgs::CameraInfo, sensor_msgs::CameraInfo> ApproximateDepthPolicy; 
    typedef message_filters::Synchronizer<ExactDepthPolicy> ExactDepthSync;
    typedef message_filters::Synchronizer<ApproximateDepthPolicy> ApproximateDepthSync;
    boost::shared_ptr<ExactDepthSync> exact_depth_sync_;
    boost::shared_ptr<ApproximateDepthSync> approximate_depth_sync_;

    // Action
    actionlib::SimpleActionServer<face_detector::FaceDetectorAction> as_;
    face_detector::FaceDetectorFeedback feedback_;
    face_detector::FaceDetectorResult result_;

    // If running the face detector as a component in part of a larger person tracker, this subscribes to the tracker's position measurements and whether it was initialized by some other node.
    // Todo: resurrect the person tracker.
    ros::Subscriber pos_sub_;
    bool external_init_;


    // Publishers
    // A point cloud of the face positions, meant for visualization in rviz.
    // This could be replaced by visualization markers, but they can't be modified
    // in rviz at runtime (eg the alpha, display time, etc. can't be changed.)
    ros::Publisher cloud_pub_;
    ros::Publisher pos_array_pub_;

    // Display
    bool do_display_; 
    cv::Mat cv_image_out_; 
    // Depth
    bool use_depth_; 
    image_geometry::StereoCameraModel cam_model_; 
    // Face detector params and output
    Faces *faces_; 
    string name_; 
    string haar_filename_; 
    double reliability_; 
    struct RestampedPositionMeasurement {
      ros::Time restamp;
      people_msgs::PositionMeasurement pos;
      double dist;
    };
    map<string, RestampedPositionMeasurement> pos_list_; 
    int max_id_;

    bool quit_;

    tf::TransformListener tf_;

    std::string fixed_frame_;

    boost::mutex cv_mutex_, pos_mutex_, limage_mutex_, dimage_mutex_;

    bool do_continuous_; 
    bool do_publish_unknown_; 
    FaceDetector(std::string name) :
      BIGDIST_M(1000000.0),
      it_(nh_),
      as_(nh_, name, false),
      faces_(0),
      max_id_(-1),
      quit_(false)
    {
      ROS_INFO_STREAM_NAMED("face_detector","Constructing FaceDetector.");

      // Action stuff
      as_.registerGoalCallback(boost::bind(&FaceDetector::goalCB, this));
      as_.registerPreemptCallback(boost::bind(&FaceDetector::preemptCB, this));
      as_.start();

      faces_ = new Faces();
      double face_size_min_m, face_size_max_m, max_face_z_m, face_sep_dist_m;
      int queue_size;
      bool approx;

      // Parameters
      ros::NodeHandle local_nh("~");
      local_nh.param("classifier_name",name_,std::string(""));
      local_nh.param("classifier_filename",haar_filename_,std::string(""));
      local_nh.param("classifier_reliability",reliability_,0.0);
      local_nh.param("do_display",do_display_,false);
      local_nh.param("do_continuous",do_continuous_,true);
      local_nh.param("do_publish_faces_of_unknown_size",do_publish_unknown_,false);
      local_nh.param("use_depth",use_depth_,true);
      local_nh.param("use_external_init",external_init_,false);
      local_nh.param("face_size_min_m",face_size_min_m,FACE_SIZE_MIN_M);
      local_nh.param("face_size_max_m",face_size_max_m,FACE_SIZE_MAX_M);
      local_nh.param("max_face_z_m",max_face_z_m,MAX_FACE_Z_M);
      local_nh.param("face_separation_dist_m",face_sep_dist_m,FACE_SEP_DIST_M);
      local_nh.param("use_rgbd",use_rgbd_,false);
      local_nh.param("queue_size", queue_size, 5);
      local_nh.param("approximate_sync", approx, false);

      if (do_display_) {
        // OpenCV: pop up an OpenCV highgui window
        cv::namedWindow("Face detector: Face Detection", CV_WINDOW_AUTOSIZE);
      }

      // Init the detector and subscribe to the images and camera parameters. One case for rgbd, one for stereo.
      if (use_rgbd_) {

        faces_->initFaceDetectionDepth(1, haar_filename_, face_size_min_m, face_size_max_m, max_face_z_m, face_sep_dist_m);

        camera_ = nh_.resolveName("camera");
  image_image_ = nh_.resolveName("image_topic");
        depth_image_ = nh_.resolveName("depth_topic");
  depth_ns_ = nh_.resolveName("depth_ns");
        camera_topic_ = ros::names::clean(camera_ + "/rgb/" + image_image_);
        depth_topic_ = ros::names::clean(camera_ + "/" + depth_ns_ + "/" + depth_image_);
        camera_info_topic_ = ros::names::clean(camera_ + "/rgb/camera_info");
        depth_info_topic_ = ros::names::clean(camera_ + "/" + depth_ns_ + "/camera_info");

        local_nh.param("fixed_frame", fixed_frame_, std::string("camera_rgb_optical_frame"));

        if (approx)
        {
          approximate_depth_sync_.reset( new ApproximateDepthSync(ApproximateDepthPolicy(queue_size),
                                                                  image_sub_, depth_image_sub_, c1_info_sub_, c2_info_sub_));
          approximate_depth_sync_->registerCallback(boost::bind(&FaceDetector::imageCBAllDepth,
                                                                this, _1, _2, _3, _4));
        }
        else
        {
          exact_depth_sync_.reset( new ExactDepthSync(ExactDepthPolicy(queue_size),
                                                      image_sub_, depth_image_sub_, c1_info_sub_, c2_info_sub_));
          exact_depth_sync_->registerCallback(boost::bind(&FaceDetector::imageCBAllDepth,
                                                          this, _1, _2, _3, _4));
        }

      }
      else { 
        faces_->initFaceDetectionDisparity(1, haar_filename_, face_size_min_m, face_size_max_m, max_face_z_m, face_sep_dist_m);

        stereo_namespace_ = nh_.resolveName("camera");
        image_image_ = nh_.resolveName("image");
        left_topic_ = ros::names::clean(stereo_namespace_ + "/left/" + image_image_);
        disparity_topic_ = ros::names::clean(stereo_namespace_ + "/disparity");
        left_camera_info_topic_ = ros::names::clean(stereo_namespace_ + "/left/camera_info");
        right_camera_info_topic_ = ros::names::clean(stereo_namespace_ + "/right/camera_info");

        local_nh.param("fixed_frame", fixed_frame_, stereo_namespace_.append("_optical_frame"));

        if (approx)
        {
          approximate_disp_sync_.reset( new ApproximateDispSync(ApproximateDispPolicy(queue_size),
                                                                image_sub_, disp_image_sub_, c1_info_sub_, c2_info_sub_));
          approximate_disp_sync_->registerCallback(boost::bind(&FaceDetector::imageCBAllDisp,
                                                               this, _1, _2, _3, _4));
        }
        else
        {
          exact_disp_sync_.reset( new ExactDispSync(ExactDispPolicy(queue_size),
                                                    image_sub_, disp_image_sub_, c1_info_sub_, c2_info_sub_));
          exact_disp_sync_->registerCallback(boost::bind(&FaceDetector::imageCBAllDisp,
                                                         this, _1, _2, _3, _4));
        }
      }
      
      // Connection callbacks and advertise
      ros::SubscriberStatusCallback pos_pub_connect_cb = boost::bind(&FaceDetector::connectCb, this);
      ros::SubscriberStatusCallback cloud_pub_connect_cb = boost::bind(&FaceDetector::connectCb, this);
      if (do_continuous_)
        ROS_INFO_STREAM_NAMED("face_detector","You must subscribe to one of FaceDetector's outbound topics or else it will not publish anything.");

      {
        boost::mutex::scoped_lock lock(connect_mutex_);

        // Advertise a position measure message.
        pos_array_pub_ = nh_.advertise<people_msgs::PositionMeasurementArray>("face_detector/people_tracker_measurements_array",1, pos_pub_connect_cb, pos_pub_connect_cb);

        cloud_pub_ = nh_.advertise<sensor_msgs::PointCloud>("face_detector/faces_cloud",0, cloud_pub_connect_cb, cloud_pub_connect_cb);
      }


      // If running as an action server, just stay connected so that action calls are fast.
      if (!do_continuous_) connectCb();

      ros::MultiThreadedSpinner s(2);
      ros::spin(s);

    }

    ~FaceDetector()
    {

      cv_image_out_.release();

      if (do_display_) {
        cv::destroyWindow("Face detector: Face Detection");
      }

      if (faces_) {delete faces_; faces_ = 0;}
    }

    // Handles (un)subscribing when clients (un)subscribe
    void connectCb()
    {
      boost::mutex::scoped_lock lock(connect_mutex_);
      if (use_rgbd_) 
      {
        if (do_continuous_ && cloud_pub_.getNumSubscribers() == 0 && pos_array_pub_.getNumSubscribers() == 0)
        {
          ROS_INFO_STREAM_NAMED("face_detector","You have unsubscribed to FaceDetector's outbound topics, so it will no longer publish anything.");
          image_sub_.unsubscribe();
          depth_image_sub_.unsubscribe();
          c1_info_sub_.unsubscribe();
          c2_info_sub_.unsubscribe();
          pos_sub_.shutdown();
        }
        else if (!do_continuous_ || !image_sub_.getSubscriber())
        {
          image_sub_.subscribe(it_, camera_topic_, 3);
          depth_image_sub_.subscribe(it_, depth_topic_, 3);
          c1_info_sub_.subscribe(nh_, camera_info_topic_, 3);
          c2_info_sub_.subscribe(nh_, depth_info_topic_,3);   
          // // Subscribe to filter measurements.
          // if (external_init_) {
          //   //pos_sub_ = nh_.subscribe("people_tracker_filter",1,&FaceDetector::posCallback,this);
          //   pos_sub_ = nh_.subscribe("/face_detector/people_tracker_measurements_array",1,&FaceDetector::posCallback,this);
          // }
        }
      } 
      else
      {
        if (do_continuous_ && cloud_pub_.getNumSubscribers() == 0 && pos_array_pub_.getNumSubscribers() == 0)
        {
          ROS_INFO_STREAM_NAMED("face_detector","You have unsubscribed to FaceDetector's outbound topics, so it will no longer publish anything.");
          image_sub_.unsubscribe();
          disp_image_sub_.unsubscribe();
          c1_info_sub_.unsubscribe();
          c2_info_sub_.unsubscribe();
          pos_sub_.shutdown();
        }
        else if (!do_continuous_ || !image_sub_.getSubscriber())
        {
          image_sub_.subscribe(it_, left_topic_, 3);
          disp_image_sub_.subscribe(nh_, disparity_topic_, 3);
          c1_info_sub_.subscribe(nh_, left_camera_info_topic_, 3);
          c2_info_sub_.subscribe(nh_, right_camera_info_topic_, 3);     
          // // Subscribe to filter measurements.
          // if (external_init_) {
          //   //pos_sub_ = nh_.subscribe("people_tracker_filter",1,&FaceDetector::posCallback,this);
          //   pos_sub_ = nh_.subscribe("/face_detector/people_tracker_measurements_array",1,&FaceDetector::posCallback,this);
          // }
        }
      }
    }


    void goalCB() {
      as_.acceptNewGoal();
    }

    void preemptCB() {
      as_.setPreempted();
    }


    // void posCallback(const people_msgs::PositionMeasurementArrayConstPtr& pos_array_ptr) {

    //   // Put the incoming position into the position queue. It'll be processed in the next image callback.
    //   boost::mutex::scoped_lock lock(pos_mutex_);

    //   map<string, RestampedPositionMeasurement>::iterator it;
    //   for (uint ipa = 0; ipa < pos_array_ptr->people.size(); ipa++) {
    //     it = pos_list_.find(pos_array_ptr->people[ipa].object_id);
    //     RestampedPositionMeasurement rpm;
    //     rpm.pos = pos_array_ptr->people[ipa];
    //     rpm.restamp = pos_array_ptr->people[ipa].header.stamp;
    //     rpm.dist = BIGDIST_M;
    //     if (it == pos_list_.end()) {
    //  pos_list_.insert(pair<string, RestampedPositionMeasurement>(pos_array_ptr->people[ipa].object_id, rpm));
    //     }
    //     else if ((pos_array_ptr->people[ipa].header.stamp - (*it).second.pos.header.stamp) > ros::Duration().fromSec(-1.0) ){
    //  (*it).second = rpm;
    //     }
    //   }
    //   lock.unlock();

    // }

    // Workaround to convert a DisparityImage->Image into a shared pointer for cv_bridge in imageCBAll.
    struct NullDeleter
    {
      void operator()(void const *) const {}
    };

    void imageCBAllDepth(const sensor_msgs::Image::ConstPtr &image, const sensor_msgs::Image::ConstPtr& depth_image, const sensor_msgs::CameraInfo::ConstPtr& c1_info, const sensor_msgs::CameraInfo::ConstPtr& c2_info)
    {

      // Only run the detector if in continuous mode or the detector was turned on through an action invocation.
      if (!do_continuous_ && !as_.isActive())
        return; 

      // Clear out the result vector.
      result_.face_positions.clear();

      if (do_display_) {
        cv_mutex_.lock();
      }

      // ROS --> OpenCV
      cv_bridge::CvImageConstPtr cv_image_ptr = cv_bridge::toCvShare(image,"bgr8");
      cv_bridge::CvImageConstPtr cv_depth_ptr = cv_bridge::toCvShare(depth_image);
      cv::Mat depth_32fc1 = cv_depth_ptr->image;
      if(depth_image->encoding != "32FC1") {
        cv_depth_ptr->image.convertTo(depth_32fc1, CV_32FC1, 0.001);
      }



      cam_model_.fromCameraInfo(c1_info,c2_info);

      // For display, keep a copy of the image that we can draw on.
      if (do_display_) {
        cv_image_out_ = (cv_image_ptr->image).clone();
      }

      struct timeval timeofday;
      gettimeofday(&timeofday,NULL);
      ros::Time starttdetect = ros::Time().fromNSec(1e9*timeofday.tv_sec + 1e3*timeofday.tv_usec);

      vector<Box2D3D> faces_vector = faces_->detectAllFacesDepth(cv_image_ptr->image, 1.0, depth_32fc1, &cam_model_);
      gettimeofday(&timeofday,NULL);
      ros::Time endtdetect = ros::Time().fromNSec(1e9*timeofday.tv_sec + 1e3*timeofday.tv_usec);
      ros::Duration diffdetect = endtdetect - starttdetect;
      ROS_INFO_STREAM_NAMED("face_detector","Detection duration = " << diffdetect.toSec() << "sec");

      matchAndDisplay(faces_vector, image->header);
    }

    void imageCBAllDisp(const sensor_msgs::Image::ConstPtr &image, const stereo_msgs::DisparityImage::ConstPtr& disp_image, const sensor_msgs::CameraInfo::ConstPtr& c1_info, const sensor_msgs::CameraInfo::ConstPtr& c2_info)
    {

      // Only run the detector if in continuous mode or the detector was turned on through an action invocation.
      if (!do_continuous_ && !as_.isActive())
        return;

      // Clear out the result vector.
      result_.face_positions.clear();

      if (do_display_) {
        cv_mutex_.lock();
      }


      // ROS --> OpenCV
      cv_bridge::CvImageConstPtr cv_image_ptr = cv_bridge::toCvShare(image,sensor_msgs::image_encodings::BGR8);
      cv_bridge::CvImageConstPtr cv_disp_ptr = cv_bridge::toCvShare(disp_image->image, disp_image);
      cam_model_.fromCameraInfo(c1_info,c2_info);

      // For display, keep a copy of the image that we can draw on.
      if (do_display_) {
        cv_image_out_ = (cv_image_ptr->image).clone();
      }

      struct timeval timeofday;
      gettimeofday(&timeofday,NULL);
      ros::Time starttdetect = ros::Time().fromNSec(1e9*timeofday.tv_sec + 1e3*timeofday.tv_usec);

      vector<Box2D3D> faces_vector = faces_->detectAllFacesDisparity(cv_image_ptr->image, 1.0, cv_disp_ptr->image, &cam_model_);
      gettimeofday(&timeofday,NULL);
      ros::Time endtdetect = ros::Time().fromNSec(1e9*timeofday.tv_sec + 1e3*timeofday.tv_usec);
      ros::Duration diffdetect = endtdetect - starttdetect;
      ROS_INFO_STREAM_NAMED("face_detector","Detection duration = " << diffdetect.toSec() << "sec");

      matchAndDisplay(faces_vector, image->header);
    }


  private:

    void matchAndDisplay( vector<Box2D3D> faces_vector, std_msgs::Header header ) 
    {
      bool found_faces = false;

      int ngood = 0;
      sensor_msgs::PointCloud cloud;
      cloud.header.stamp = header.stamp;
      cloud.header.frame_id = header.frame_id;

      if (faces_vector.size() > 0 ) {

        // Transform the positions of the known faces and remove anyone who hasn't had an update in a long time.
        //      boost::mutex::scoped_lock pos_lock(pos_mutex_);
        map<string, RestampedPositionMeasurement>::iterator it;
        it = pos_list_.begin();
        while (it != pos_list_.end()) {
          if ((header.stamp - (*it).second.restamp) > ros::Duration().fromSec(5.0)) {
            // Position is too old, remove the person.
            pos_list_.erase(it++);
          }
          else {
            // Transform the person to this time. Note that the pos time is updated but not the restamp.
            tf::Point pt;
            tf::pointMsgToTF((*it).second.pos.pos, pt);
            tf::Stamped<tf::Point> loc(pt, (*it).second.pos.header.stamp, (*it).second.pos.header.frame_id);
            try {
              tf_.transformPoint(header.frame_id, header.stamp, loc, fixed_frame_, loc);
              (*it).second.pos.header.stamp = header.stamp;
              (*it).second.pos.pos.x = loc[0];
              (*it).second.pos.pos.y = loc[1];
              (*it).second.pos.pos.z = loc[2];
            }
            catch (tf::TransformException& ex) {
            }
            it++;
          }
        }
        // End filter face position update

        // Associate the found faces with previously seen faces, and publish all good face centers.
        Box2D3D *one_face;
        people_msgs::PositionMeasurement pos;
        people_msgs::PositionMeasurementArray pos_array;

        for (uint iface = 0; iface < faces_vector.size(); iface++) {
          one_face = &faces_vector[iface];

          if (one_face->status=="good" || (one_face->status=="unknown" && do_publish_unknown_)) {

            std::string id = "";

            // Convert the face format to a PositionMeasurement msg.
            pos.header.stamp = header.stamp;
            pos.name = name_;
            pos.pos.x = one_face->center3d.x;
            pos.pos.y = one_face->center3d.y;
            pos.pos.z = one_face->center3d.z;
            pos.header.frame_id = header.frame_id;//"*_optical_frame";
            pos.reliability = reliability_;
            pos.initialization = 1;//0;
            pos.covariance[0] = 0.04; pos.covariance[1] = 0.0;  pos.covariance[2] = 0.0;
            pos.covariance[3] = 0.0;  pos.covariance[4] = 0.04; pos.covariance[5] = 0.0;
            pos.covariance[6] = 0.0;  pos.covariance[7] = 0.0;  pos.covariance[8] = 0.04;

            // Check if this person's face is close enough to one of the previously known faces and associate it with the closest one.
            // Otherwise publish it with an empty id.
            // Note that multiple face positions can be published with the same id, but ids in the pos_list_ are unique. The position of a face in the list is updated with the closest found face.
            double dist, mindist = BIGDIST_M;
            map<string, RestampedPositionMeasurement>::iterator close_it = pos_list_.end();
            for (it = pos_list_.begin(); it != pos_list_.end(); it++) {
              dist = pow((*it).second.pos.pos.x - pos.pos.x, 2.0) + pow((*it).second.pos.pos.y - pos.pos.y, 2.0) + pow((*it).second.pos.pos.z - pos.pos.z, 2.0);
              if (dist <= faces_->face_sep_dist_m_ && dist < mindist) {
                mindist = dist;
                close_it = it;
              }
            }
            if (close_it != pos_list_.end()) {
              pos.object_id = (*close_it).second.pos.object_id;
              if (mindist < (*close_it).second.dist) {
                (*close_it).second.restamp = header.stamp;
                (*close_it).second.dist = mindist;
                (*close_it).second.pos = pos;
              }
              ROS_INFO_STREAM_NAMED("face_detector","Found face to match with id " << pos.object_id);
            }
            else {
              max_id_++;
              pos.object_id = static_cast<ostringstream*>( &(ostringstream() << max_id_) )->str();
              ROS_INFO_STREAM_NAMED("face_detector","Didn't find face to match, starting new ID " << pos.object_id);
            }
            result_.face_positions.push_back(pos);
            found_faces = true;

          }

        }
        pos_array.header.stamp = header.stamp;
        pos_array.header.frame_id = header.frame_id;
        pos_array.people = result_.face_positions;
        if (pos_array.people.size() > 0) {
          pos_array_pub_.publish(pos_array);

          // Update the position list greedily. This should be rewritten.
          map<string, RestampedPositionMeasurement>::iterator it;
          for (uint ipa = 0; ipa < pos_array.people.size(); ipa++) {
            it = pos_list_.find(pos_array.people[ipa].object_id);
            RestampedPositionMeasurement rpm;
            rpm.pos = pos_array.people[ipa];
            rpm.restamp = pos_array.people[ipa].header.stamp;
            rpm.dist = BIGDIST_M;
            if (it == pos_list_.end()) {
              pos_list_.insert(pair<string, RestampedPositionMeasurement>(pos_array.people[ipa].object_id, rpm));
            }
            else if ((pos_array.people[ipa].header.stamp - (*it).second.pos.header.stamp) > ros::Duration().fromSec(-1.0) ){
              (*it).second = rpm;
            }
          }
          //      pos_lock.unlock();

          // Clean out all of the distances in the pos_list_
          for (it = pos_list_.begin(); it != pos_list_.end(); it++) {
            (*it).second.dist = BIGDIST_M;
          }

        }


        // Done associating faces

        /******** Display **************************************************************/

        // Publish a point cloud of face centers.

        cloud.channels.resize(1);
        cloud.channels[0].name = "intensity";

        for (uint iface = 0; iface < faces_vector.size(); iface++) {
          one_face = &faces_vector[iface];

          // Visualization of good faces as a point cloud
          if (one_face->status == "good") {

            geometry_msgs::Point32 p;
            p.x = one_face->center3d.x;
            p.y = one_face->center3d.y;
            p.z = one_face->center3d.z;
            cloud.points.push_back(p);
            cloud.channels[0].values.push_back(1.0f);

            ngood ++;
          }
        }

        cloud_pub_.publish(cloud);
        // Done publishing the point cloud.

      } // Done if faces_vector.size() > 0
    

      // Draw an appropriately colored rectangle on the display image and in the visualizer.
      if (do_display_) {
        displayFacesOnImage(faces_vector);
        cv_mutex_.unlock();
      }
      // Done drawing.

      /******** Done display **********************************************************/

      ROS_INFO_STREAM_NAMED("face_detector","Number of faces found: " << faces_vector.size() << ", number with good depth and size: " << ngood);

      // If you don't want continuous processing and you've found at least one face, turn off the detector.
      if (!do_continuous_ && found_faces) {
        as_.setSucceeded(result_);
      }
    }

    // Draw bounding boxes around detected faces on the cv_image_out_ and show the image. 
    void displayFacesOnImage(vector<Box2D3D>  faces_vector) 
    {

      Box2D3D *one_face;
    
      for (uint iface = 0; iface < faces_vector.size(); iface++) {
        one_face = &faces_vector[iface];
        // Visualization by image display.
        if (do_display_) {
          cv::Scalar color;
          if (one_face->status == "good") {
            color = cv::Scalar(0,255,0);
          }
          else if (one_face->status == "unknown") {
            color = cv::Scalar(255,0,0);
          }
          else {
            color = cv::Scalar(0,0,255);
          }
        
          cv::rectangle(cv_image_out_, 
                        cv::Point(one_face->box2d.x,one_face->box2d.y), 
                        cv::Point(one_face->box2d.x+one_face->box2d.width, one_face->box2d.y+one_face->box2d.height), color, 4);
        }
      }

      cv::imshow("Face detector: Face Detection",cv_image_out_);
      cv::waitKey(2);
    
    }


  }; // end class

}; // end namespace people

// Main
int main(int argc, char **argv)
{
  ros::init(argc,argv,"face_detector");

  people::FaceDetector fd(ros::this_node::getName());

  return 0;
}