TimeSynchronizer while subscribing to two camera topics using ROS2 - Foxy

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Refer to code snippet below, this was quite troublesome to get it working but this code is known to be working under Foxy

typedef message_filters::sync_policies::ApproximateTime<sensor_msgs::msg::Image,
                sensor_msgs::msg::Image>
              RGBDApprxTimeSyncPolicy;
            typedef message_filters::Synchronizer<RGBDApprxTimeSyncPolicy> RGBDApprxTimeSyncer;

            // subscriber for color cam in case rgbd camera model localization
            message_filters::Subscriber<sensor_msgs::msg::Image> rgbd_color_image_subscriber_;
            // subscriber for depth cam in case rgbd camera model localization
            message_filters::Subscriber<sensor_msgs::msg::Image> rgbd_depth_image_subscriber_;


        void rgbdCallback(
              const sensor_msgs::msg::Image::ConstSharedPtr & color,
              const sensor_msgs::msg::Image::ConstSharedPtr & depth);

              rgbd_color_image_subscriber_.subscribe(
                this, "camera/color/image_raw",
                rmw_qos_profile_sensor_data);
              rgbd_depth_image_subscriber_.subscribe(
                this, "camera/depth/image_raw",
                rmw_qos_profile_sensor_data);
              rgbd_approx_time_syncher_.reset(
                new RGBDApprxTimeSyncer(
                  RGBDApprxTimeSyncPolicy(10),
                  rgbd_color_image_subscriber_,
                  rgbd_depth_image_subscriber_));
              rgbd_approx_time_syncher_->registerCallback(
                std::bind(
                  &YourClass::rgbdCallback, this, std::placeholders::_1,
                  std::placeholders::_2));

    void YourClass::rgbdCallback(
        const sensor_msgs::msg::Image::ConstSharedPtr & color,
        const sensor_msgs::msg::Image::ConstSharedPtr & depth)
      {

        auto colorcv = cv_bridge::toCvShare(color)->image;
        auto depthcv = cv_bridge::toCvShare(depth)->image;
        if (colorcv.empty() || depthcv.empty()) {
          return;
        }
       // do something with recieved messages

    }