DDC/CI Monitor Brightness

UUID: ddcci-monitor-control@andr35
Last edited:
2 years ago 2021-02-21, 16:34
Last commit: [b3204d46] ddcci-monitor-control@andr35: update applet icon name (#3613)

Adjust external monitor brightness and contrast



DDC/CI Monitor Brightness

A Cinnamon applet that let adjust brightness and contrast of external an monitor thanks to the DCC/CI channel.


In order to function correctly this applet requires ddcutil.

It can be installed following these steps:

  1. Install ddcutil and i2c-tools using:

    sudo apt install ddcutil i2c-tools
  2. To let ddcutil work without requiring root priviledges, the user must be part of the i2c group. Run the following command to add the current user to the i2c group.

    sudo usermod -aG i2c $USER

    After having executed the command, log out to apply the new configuration.

More information on how to install ddcutil can be found here in section "Tool 2".

You can check if ddcutil has been installed correctly and the monitor supports the DDC/CI protocol running:

ddcutil capabilities

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Wolfs01-3 months ago
Very nice! Though I had to restart to add my user to i2c, relogging didn't suffice
Herpderpus666-3 years ago
Kinda works, but the icon is missing on my Linux Mint 20. Also, the contrast slider appears and disappears making it a bit hard to use.
Andr35-3 years ago
The slider disappears when the applet asks for the current brightness and contrast values to the monitor. This operation might take a while. Unfortunately, during this period of time I noticed that it is not possible to set a new brightness/contrast value. So, the slider is temporarily hidden.