usb_camera_driver.cpp

/*
Copyright (c) 2019 Andreas Klintberg

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

#include <chrono>
#include <cstdio>
#include <memory>
#include <string>

#include "usb_camera_driver.hpp"


using namespace std::chrono_literals;

CameraDriver::CameraDriver(std::shared_ptr<rclcpp::Node>  const nh) : nh_(nh),
image_pub_(nh_),
cinfo_manager_(nh_.get()) {
    std::cout << "intialize camera info manager and advertiseCamera" << std::endl;
    camera_info_pub_ = image_pub_.advertiseCamera("image_raw", 1, false);
};


std::shared_ptr<sensor_msgs::msg::Image> CameraDriver::ConvertFrameToMessage(const cv::Mat & frame)
{
    std_msgs::msg::Header header;
    img_bridge = cv_bridge::CvImage(header, sensor_msgs::image_encodings::BGR8, frame);
    image_msg_ = img_bridge.toImageMsg(); // from cv_bridge to sensor_msgs::msg::Image
    return image_msg_;
}


void CameraDriver::ImageCallback() {
    cap >> frame;
    if (!frame.empty()) {
        // Convert to a ROS image
        if (!is_flipped) {
            image_msg_ = ConvertFrameToMessage(frame);
        } else {
            // Flip the frame if needed
            cv::flip(frame, flipped_frame, 1);
            image_msg_ = ConvertFrameToMessage(frame);
        }
        
        // Publish the image message and increment the frame_id.
        RCLCPP_INFO(nh_->get_logger(), "Publishing image");
        
        // Put the message into a queue to be processed by the middleware.
        // This call is non-blocking.
        sensor_msgs::msg::CameraInfo::SharedPtr camera_info_msg_(
                                                                 new sensor_msgs::msg::CameraInfo(cinfo_manager_.getCameraInfo()));
        
        camera_info_pub_.publish(image_msg_, camera_info_msg_);
    }
}

bool CameraDriver::Start(){
    
    /* get ROS2 config parameter for camera calibration file */
    auto camera_calibration_file_param_ = nh_->declare_parameter("camera_calibration_file", "file://config/camera.yaml");
    cinfo_manager_.loadCameraInfo(camera_calibration_file_param_);
    
    cap.open(0);
    
    size_t width = 320;
    size_t height = 240;

    cap.set(cv::CAP_PROP_FRAME_WIDTH, static_cast<double>(width));
    cap.set(cv::CAP_PROP_FRAME_HEIGHT, static_cast<double>(height));
    
    timer_ = nh_->create_wall_timer(100ms, std::bind(&CameraDriver::ImageCallback, this));
    
    return true;
}