How do you get boundary box information from the subscriber code and draw the box in the imported video based on that information?

[Lee-Siyoung]

I will send boundingbox information and video from Jetson to another computer and draw yolo box. But there was an error in the catkin_make process.

In the main function this is my code:

void imageCallback(const sensor_msgs::ImageConstPtr& msg, const darknet_ros_msgs::BoundingBoxes::ConstPtr& bbox)
{
  try
  {
    cv::Mat real = cv_bridge::toCvShare(msg, "bgr8")->image;
    if(bbox->bounding_boxes[0].probability > 0.0)
    {
        cv::rectangle(real, (bbox->bounding_boxes[0].xmin, bbox->bounding_boxes[0].ymin), (bbox->bounding_boxes[0].xmax, bbox->bounding_boxes[0].ymax),(0,0,255), 2);
    }

    cv::imshow("view", real);
  }
  catch (cv_bridge::Exception& e)
  {
    ROS_ERROR("cannot decode image");
  }

  cv::waitKey(1);
}

int main(int argc, char **argv)
{
  ros::init(argc, argv, "opencv_sub");

  cv::namedWindow("view");
  cv::startWindowThread();

  ros::NodeHandle nh;
  ros::Subscriber sub = nh.subscribe("/camera/color/image_raw", 1000, imageCallback);
  ros::Subscriber cood_sub = nh.subscribe("/darknet_ros/bounding_boxes",100, msgCallback);
  ros::spin();
  cv::destroyWindow("view");
}

void msgCallback(const darknet_ros_msgs::BoundingBoxes::ConstPtr& msg)
{
    cout<<"Bouding Boxes (header):" << msg->header <<endl;
    cout<<"Bouding Boxes (image_header):" << msg->image_header <<endl;
    cout<<"Bouding Boxes (Class):" << msg->bounding_boxes[0].Class <<endl;
    cout<<"Bouding Boxes (xmin):" << msg->bounding_boxes[0].xmin <<endl;
    cout<<"Bouding Boxes (xmax):" << msg->bounding_boxes[0].xmax <<endl;
    cout<<"Bouding Boxes (ymin):" << msg->bounding_boxes[0].ymin <<endl;
    cout<<"Bouding Boxes (ymax):" << msg->bounding_boxes[0].ymax <<endl;
    cout<<"Bouding Boxes (probability):" << msg->bounding_boxes[0].probability <<endl;
    cout<<"\033[2J\033[1;1H";     // clear terminal

}

I'm a beginner at ros, opencv. Can you help me?

It's error

---

the callback should have only one parameter in its signature. So I changed it to the code below, but I'm not getting any information from the boundingbox.

void imageCallback(const sensor_msgs::ImageConstPtr& msg)
{
  try
  {
    cv::Mat real = cv_bridge::toCvShare(msg, "bgr8")->image;
    if(darknet_ros_msgs::BoundingBoxes::bounding_boxes[0].probability > 0.0)
    {
        cv::rectangle(real, (darknet_ros_msgs::BoundingBoxes::bounding_boxes[0].xmin, darknet_ros_msgs::BoundingBoxes::bounding_boxes[0].ymin), (darknet_ros_msgs::BoundingBoxes::bounding_boxes[0].xmax, darknet_ros_msgs::BoundingBoxes::bounding_boxes[0].ymax),(0,0,255), 2);
    }
    cv::imshow("view", real);
  }
  catch (cv_bridge::Exception& e)
  {
    ROS_ERROR("cannot decode image");
  }
  cv::waitKey(1);
}

int main(int argc, char **argv)
{
  ros::init(argc, argv, "opencv_sub");

  cv::namedWindow("view");
  cv::startWindowThread();
  ros::NodeHandle nh;
  ros::Subscriber sub = nh.subscribe("/camera/color/image_raw", 1000, imageCallback);
  ros::Subscriber cood_sub = nh.subscribe("/darknet_ros/bounding_boxes",100, msgCallback);
  ros::spin();
  cv::destroyWindow("view");
}

void msgCallback(const darknet_ros_msgs::BoundingBoxes::ConstPtr& msg)
{
    cout<<"Bouding Boxes (header):" << msg->header <<endl;
    cout<<"Bouding Boxes (image_header):" << msg->image_header <<endl;
    cout<<"Bouding Boxes (Class):" << msg->bounding_boxes[0].Class <<endl;
    cout<<"Bouding Boxes (xmin):" << msg->bounding_boxes[0].xmin <<endl;
    cout<<"Bouding Boxes (xmax):" << msg->bounding_boxes[0].xmax <<endl;
    cout<<"Bouding Boxes (ymin):" << msg->bounding_boxes[0].ymin <<endl;
    cout<<"Bouding Boxes (ymax):" << msg->bounding_boxes[0].ymax <<endl;
    cout<<"Bouding Boxes (probability):" << msg->bounding_boxes[0].probability <<endl;
    cout<<"\033[2J\033[1;1H";     // clear terminal
}

I've solved it. :)