线程和ros::ok()在ROS中不工作

Question

我有一个由std：：线程执行的函数。我希望它能够工作，直到用户通过按Ctrl+C关闭运行roscore的终端为止。

void publish_camera_on_topic(std::vector<Camera> cameras, const std::vector<ros::Publisher> publishers, const int camera_index)
{ 
  
  int frameSize;
  BYTE *imagePtr;

  // frame id
  int frame_id = 0;

  cv_bridge::CvImage img_bridge;
  sensor_msgs::Image img_msg;

  while (ros::ok()) {
    // Grab and display a single image from each camera
    
    imagePtr = cameras[camera_index].getRawImage();

    frameSize = cameras[camera_index].getFrameSize();

    cameras[camera_index].createRGBImage(imagePtr,frameSize);

    unsigned char* pImage = cameras[camera_index].getImage();
    if (NULL != pImage) {

      Mat image(cameras[camera_index].getMatSize(), CV_8UC3, pImage, Mat::AUTO_STEP);

      // release asap
      cameras[camera_index].releaseImage(); 

      //cvtColor(image, image, CV_BGR2RGB,3);

      // publish on ROS topic
      std_msgs::Header header; // empty header
      header.seq = frame_id; // user defined counter
      header.stamp = ros::Time::now(); // time
      img_bridge = cv_bridge::CvImage(header, sensor_msgs::image_encodings::RGB8, image);
      img_bridge.toImageMsg(img_msg); // from cv_bridge to sensor_msgs::Image
      publishers[camera_index].publish(img_msg); // ros::Publisher pub_img = node.advertise<sensor_msgs::Image>("topic", queuesize);

    }

    // increase frame Id
    frame_id = frame_id + 1;
  }

  std::cout << "ROS closing for thread of camera " << camera_index << " recieved." << std::endl;

}

此外，我创建这样的线程：

 // image publisher 
  // for each camera create an publisher
  std::vector<ros::Publisher> publishers;
  for (size_t i = 0; i < cameras.size(); i++) {
    char topic_name[200];
    sprintf(topic_name, "/lumenera_camera_package/%d", i + 1);
    publishers.push_back(nh.advertise<sensor_msgs::Image>(topic_name, 10));
  }
  
  // work with each camera on a seprate thread
  std::vector<std::thread> thread_vector;
  for(size_t i=0; i < cameras.size(); i++) {
    thread_vector.push_back(std::thread(publish_camera_on_topic, cameras, publishers, i));
  }

  ros::spin();

  std::for_each(thread_vector.begin(), thread_vector.end(), [](std::thread &t){t.join(); });

  for(size_t i=0; i < cameras.size(); i++) {
    cameras[i].stopStreaming();
  }

  ROS_INFO("Node: [lumenera_camera_node] has been Ended.");

但是，当我在终端中按Ctrl+C并停止roscore时，线程将继续运行，并且ros::ok()的值不会改变。

Answer 1

问题解决了。问题是ros::ok()不检查ROS母版。而不是这一行：

while (ros::ok()) { //do sth}

应使用这一行：

while (ros::ok() && ros::master::check()) { // do sth}