Have a computer monitor supports DDC/CI protocol? There’s now a free and open-source graphical tool to control the brightness of your display.
Display Data Channel (DDC) / Command Interface (CI) is a type of communication between the computer and the monitor.
Most monitors today support DDC/CI, but not many people have heard of it, since most manufacturers do not develop proprietary software for the feature.
And ddcbc-gtk is a free open-source GTK tool for controlling brightness through the DDC/CI protocol. It includes support for controlling the brightness of multiple displays.
If you have computer monitors purchased in the past few years, DDC/CI should be supported. After enabled the feature via your monitor’s physical settings button, installing
ddcbc-gtk will allow you to control the display brightness in Linux desktop.
How to Install ddcbc-gtk in Ubuntu 20.04 +, Linux Mint 20
1. First open
terminal from your system application launcher. When it opens, run command to install some required libraries:
sudo apt install libgtk3-dev gcc
2. Ubuntu 20.04 users need to add the developer’s PPA for the ddcutil development library:
sudo add-apt-repository ppa:rockowitz/ddcutil
Then install the ddcutil libraries via command:
sudo apt install ddcutil libddcutil-dev
3. To ensure you have the permission to access to the i2c devices. Run following commands one by one:
- Create i2c group if it does not exist:
sudo groupadd --system i2c
- Add your user to the group:
sudo usermod YOUR_USER_NAME -aG i2c
- Copy the udev rule to /etc:
sudo cp /usr/share/ddcutil/data/45-ddcutil-i2c.rules /etc/udev/rules.d
- For testing, just give read write permission to the i2c devices:
sudo chmod a+rw /dev/i2c-*
4. Finally grab the source code, build, and run the software via commands:
- Download the source coe via command:
git clone --recurse-submodules https://github.com/ahshabbir/ddcbc-gtk.git
- Then navigate to the source folder, run the script to build the application:
cd ddcbc-gtk && ./build.sh
- Then you’re able to launch the tool from the directory via command:
- To install the app shorcut so to open it from system application menu, run command:
The tool at the moment does not have an uninstall script. It can be however removed as easy as a few rm commands:
sudo rm /usr/bin/ddcbc-gtk
sudo rm /usr/share/applications/ddcbc-gtk.desktop