perception-msg-adapter

Introduction

The msg adapter module is used to forwarding message inside the perception module.

Channel names for internal messages usually have an inner field inner. These messages are only passed between threads, not between processes, so you can't use cyber_monitor to view them. Because these messages are generally relatively large, such as image and point cloud data, in order to avoid copying, serialization and deserialization, we use the method of directly passing objects, so these messages can only be passed within the thread.

For the convenience of debugging, you can use the msg adapter module to forward messages, so that you can view them through cyber_monitor.

Directory Structure

msg_adapter
├── BUILD       // bazel build file
├── README.md
├── common      // gflags parameters
├── convert     // convert functions
├── cyberfile.xml   // package description file
├── dag
├── launch
├── msg_adapter_component.cc   // component
├── msg_adapter_component.h
└── msg_converter.h

Modules

MsgAdapterComponent

apollo::perception::MsgAdapterComponent

Input

Input channel	Type	Description
`/perception/inner/location_refinement`	`apollo::perception::onboard::CameraFrame`	camera detection message
`/perception/lidar/detection`	`apollo::perception::onboard::LidarFrameMessage`	lidar detection message
`/perception/inner/PrefusedObjects`	`apollo::perception::onboard::SensorFrameMessage`	camera/lidar/radar tracking message

Each of the above channels corresponds to a conversion function. It is best to enable only one at a time. If multiple channels are to be enabled, it is best to modify the output channel at the same time.

Output

Out channel	Type	Description
`/apollo/perception/obstacles`	`apollo::perception::PerceptionObstacles`	obstacles detected

How to run

The msg adapter module is used with other modules to forward messages, so it is generally not started separately.

How to modify the input and output topics

You can modify input and output topics in modules/perception/data/flag/perception_common.flag.

--cameraframe_to_obstacles_in=/perception/inner/location_refinement
# --lidarframe_to_obstacles_in=/perception/lidar/detection
--sensorframe_message_to_obstacles_in=/perception/inner/PrefusedObjects

How to add my own convert function

You can follow below steps to add new convert.

Get the type of message to convert, typically including input and output messages. Add conversion function in modules/perception/msg_adapter/convert/convert.h.
Register conversion function in modules/perception/msg_adapter/msg_adapter_component.cc. And add input and output topics.