auto exposure controller for ros2

ROS2 node that subscribes to camera meta information and publishes control messages for exposure time and gain. This package works in conjunction with the flir_spinnaker_ros2 package and allows to externally control the auto-exposure which is useful in situations where two cameras have to maintain consistent exposure settings.

How to build

Make sure you have your ROS2 environment sourced, for example:

source /opt/ros/galactic/setup.bash

Create a workspace (exposure_control_ros2_ws), clone this repo, and use vcs (ubuntu package python3-vcstool to pull in the remaining dependencies:

mkdir -p ~/exposure_control_ros2_ws/src
cd ~/exposure_control_ros2_ws
git clone https://github.com/berndpfrommer/exposure_control_ros2 src/exposure_control_ros2
cd src
vcs import < exposure_control_ros2/exposure_control_ros2.repos
cd ..

Build the package:

colcon build --symlink-install --cmake-args -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
. install/setup.bash

You should now be able to launch the example node:

ros2 launch exposure_control_ros2 exposure_control.launch.py

Also have a look at the stereo_synced.launch.py file in the launch directory of the flir_spinnaker_ros2 camera driver.

Parameters

max_gain: (default 10) maximum allowed camera gain (in db)
gain_priority: (default false) if true, first vary gain, then vary exposure time.
brightness_target: (default 120) average target brightness (0..255)
brightness_tolerance: (default 5) brightness threshold before sending control command
min_exposure_time: (default 1000) minimum exposure time (microseconds)
max_exposure_time: (default 1000000) max exposure time (microseconds)

Topics

meta: camera image metadata to which the node subscribes
control: topic on which the control messages will be published

License

This software is issued under the Apache License Version 2.0.