想问一下关于代码的问题

[ghost]

大佬好，我是小白
想请问下 VLOAM-NOTED/src/vloam_main/src/vloam_main_node.cpp 里面261行左右

 // 订阅ROS图像信息
  sub_image00_ptr =
      std::make_shared<message_filters::Subscriber<sensor_msgs::Image>>(nh, "/kitti/camera_gray_left/image_raw", 10);
  // 订阅相机的参数
  sub_camera00_ptr = std::make_shared<message_filters::Subscriber<sensor_msgs::CameraInfo>>(
      nh, "/kitti/camera_gray_left/camera_info", 10);
  // 订阅激光雷达
  sub_velodyne_ptr = std::make_shared<message_filters::Subscriber<sensor_msgs::PointCloud2>>(
      nh, "/kitti/velo/pointcloud", 10);  // TODO: change the buffer size to potentially reduce the data lost

这三个订阅的数据在哪部分发布的，没找到呜呜