git clone https://github.com/splionar/exercise20.git
cd exercise20
dts devel build -f --arch amd64
docker run -it --rm --net host -v [PATH_TO_BAG_FOLDER]:/code/catkin_ws/src/exercise20/mounted_volume duckietown/exercise20:v1-amd64 /bin/bash
python packages/process_image.py mounted_volume/[BAG_FILE_NAME]
The processed image bag file will be saved inside the mounted volume.