How to initialize image_transport using rclcpp

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I am writing a camera node to publish compressed image whenever new image captured from a camera. To do this, I realized that I need to initialize image_transport with node handle however I just don't know how to do that.

Here is the code inside a class

#include "rclcpp/rclcpp.hpp"
#include "sensor_msgs/msg/image.hpp"
#include "cv_bridge/cv_bridge.h"
#include "sensor_msgs/msg/compressed_image.hpp"
#include "image_transport/image_transport.hpp"

class CamPublisher_: public rclcpp::Node
{
  public:
    CamPublisher_()
    : Node("camera")  {
        setvbuf(stdout, NULL, _IONBF, BUFSIZ);
        initialize();
    }
    ~CamPublisher_() {
        cap.release();
    }
  private:
void initialize()
    {
        topic_image = "/camera/raw";
        topic_compressed = "/camera/compressed";
        auto qos = rclcpp::QoS(rclcpp::KeepLast(10));
        pub_image = this->create_publisher<sensor_msgs::msg::Image>(
            topic_image, qos
        );
        // pub_compressed = this->create_publisher<sensor_msgs::msg::CompressedImage>(
        //  topic_compressed, qos
        // );
        pub_transport = it.advertise(topic_compressed, 10);

        cap.open(0);

        if (!cap.isOpened()) {
            RCLCPP_ERROR(this->get_logger(), "Could not open video stream");
            throw std::runtime_error("Could not open video stream");
        }
        cap.set(cv::CAP_PROP_FRAME_WIDTH, 640);
        cap.set(cv::CAP_PROP_FRAME_HEIGHT, 640);

        timer_ = this->create_wall_timer(
                std::chrono::milliseconds(static_cast<int>(1000 / 30)), // 30 fps
                std::bind(&CamPublisher_::timerCallback, this));
    }

    void timerCallback()
    {
        cv::Mat frame;
        cap >> frame;
        if (frame.empty()) {
            return;
        }
        convert_and_publish(frame);
    }

    std::string mat2encoding(int mat_type)
    {
        switch (mat_type) {
            case CV_8UC1:
                return "mono8";
            case CV_8UC3:
                return "bgr8";
            case CV_16SC1:
                return "mono16";
            case CV_8UC4:
                return "rgba8";
            default:
                std::runtime_error("Unsupported encoding type");
        }
        return 0;
    }

    void convert_and_publish(const cv::Mat& frame)
    {
        auto msg = sensor_msgs::msg::Image();
        msg.height = frame.rows;
        msg.width = frame.cols;
        msg.encoding = mat2encoding(std::move(frame.type()));
        msg.step = static_cast<sensor_msgs::msg::Image::_step_type>(frame.step);

        size_t size = frame.step * frame.rows;
        msg.data.resize(size);
        memcpy(&msg.data[0], frame.data, size);

        pub_image->publish(msg);
        sensor_msgs::msg::CompressedImage img_compressed_msg;
    }

    //vars
    cv::VideoCapture cap;

    std::string topic_image;
    std::string topic_compressed;
    rclcpp::Publisher<sensor_msgs::msg::Image>::SharedPtr pub_image;
    //rclcpp::Publisher<sensor_msgs::msg::CompressedImage>::SharedPtr pub_compressed;
    image_transport::ImageTransport it;
    image_transport::Publisher pub_transport;
    rclcpp::TimerBase::SharedPtr timer_;
};

Here is the error when I tried colcon build

ros2_ws/src/stream/src/camera.cpp: In constructor ‘CamPublisher_::CamPublisher_()’:
ros2_ws/src/stream/src/camera.cpp:27:20: error: no matching function for call to ‘image_transport::ImageTransport::ImageTransport()’
   27 |     : Node("camera")
      |                    ^
In file included from ros2_ws/src/stream/src/camera.cpp:18:
/opt/ros/foxy/include/image_transport/image_transport.hpp:116:12: note: candidate: ‘image_transport::ImageTransport::ImageTransport(rclcpp::Node::SharedPtr)’
  116 |   explicit ImageTransport(rclcpp::Node::SharedPtr node);
      |            ^~~~~~~~~~~~~~
/opt/ros/foxy/include/image_transport/image_transport.hpp:116:12: note:   candidate expects 1 argument, 0 provided
make[2]: *** [CMakeFiles/camera.dir/build.make:63: CMakeFiles/camera.dir/src/camera.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:107: CMakeFiles/camera.dir/all] Error 2
make: *** [Makefile:141: all] Error 2