hz_measure_nodelet.cpp

Go to the documentation of this file.

/*********************************************************************
 * Software License Agreement (BSD License)
 *
 *  Copyright (c) 2014, JSK Lab
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/o2r other materials provided
 *     with the distribution.
 *   * Neither the name of the Willow Garage nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *********************************************************************/

#include <pluginlib/class_list_macros.h>
#include "jsk_topic_tools/hz_measure_nodelet.h"

#include "std_msgs/Float32.h"

namespace jsk_topic_tools
{
  void HzMeasure::onInit()
  {
    pnh_ = getPrivateNodeHandle();
    if (!pnh_.getParam("message_num", average_message_num_)) {
      average_message_num_ = 10; // defaults to 10
    }
    hz_pub_ = pnh_.advertise<std_msgs::Float32>("output", 1);
    sub_ = pnh_.subscribe<topic_tools::ShapeShifter>("input", 1,
                                                     &HzMeasure::inputCallback, this);
  }

  void HzMeasure::inputCallback(const boost::shared_ptr<topic_tools::ShapeShifter const>& msg)
  {
    ros::Time now = ros::Time::now();
    buffer_.push(now);
    if (buffer_.size() > average_message_num_) {
      ros::Time oldest = buffer_.front();
      double whole_time = (now - oldest).toSec();
      double average_time = whole_time / (buffer_.size() - 1);
      std_msgs::Float32 output;
      output.data = 1.0 / average_time;
      hz_pub_.publish(output);
      buffer_.pop();
    }
    else {
      NODELET_DEBUG("there is no enough messages yet");
    }
  }
  
}

typedef jsk_topic_tools::HzMeasure HzMeasure;
PLUGINLIB_EXPORT_CLASS(HzMeasure, nodelet::Nodelet)