Demonstrate how to use shared memory with image processing algorithms.

Note this is highly experimental and requires much clean up. It may still serve as an inspiration how to set up a computer vision app in ROS 2 with shared memory for high transmission efficiency.

As of today this package only supports ROS 2 Rolling.

ROS 2 Galactic is not supported due to some cmake command changes.

Also require yolov3 object detection parameters which are automatically downloaded at build time using the scripts/download_yolo_weights.sh script.

TODO: more detail

1. Install ROS 2 Rolling

2. Clone the shm_vision_demo repo into your colcon_ws/src directory

3. Clone the iceoryx repo into your colcon_ws/src directory - parallel with the repo you just cloned in step number two

4. Build using colcon build --packages-up-to shm_vision_demo. While building it will automatically fetch the yolov3.weights file from https://pjreddie.com/darknet/yolo/ and copy them to the shm_vision_demo/config directory. The weights file is fairly large so it is not included in the repository but automatically downloaded during the build.

The following files are needed in the config/ directory:

• coco.names
• yolov3.cfg
• yolov3.weights (YOLOv3-320 for the right image size)

5. Adapt the ros2_ws variable in the scripts/demo.sh and scripts/shm_demo.sh scripts as needed. ros2_ws needs to point to the ROS 2 rolling workspace where shm_vision_demo and iceoryx are located.

By default the provided demo.sh and shm_demo.sh scripts will try to use your devices camera running live. If for some reason you do not wish to use your camera, you may pass in an argument to each script specifying an .mp4 file to use instead.

cd shm_vision_demo/scripts
# to run on live camera connected to device
./shm_demo.sh
# to run demo on pre-recorded video
./shm_demo.sh ~/videos/my_cool_video.mp4

Ensure you are in the scripts directory: cd shm_vision_demo/scripts/

Run the ./demo.sh script, it should start all applications and show the corresponding outputs. Alternatively all (or a subset of) the applications can be started on their own (cf. parameterization in the script).

stop_demo.sh stops all applications and the tmux session or alternatively enter ctrl+b then kill-session to kill the running tmux session.

Run the shm_demo.sh script, it should start all applications and show the corresponding outputs. This will automatically load the cyclonedds.xml configuration. In addition the RouDi shared memory daemon will be started with the configuration roudi_config.toml-

stop_demo.sh stops all applications and the tmux session or alternatively enter ctrl+b then kill-session to kill the running tmux session.

1. more detailed explanation and system description
2. clean up code and add more documentation
3. proper installation (scripts, config, yolo etc.)
4. extend to image pipeline, use ROS 2 executor (?)