ddcui

Communicates with a monitor's Virtual Control Panel (VCP) to query or change monitor settings,

such as brightness, red gain, and power on hours. In general, settings and information

that can be accessed using the monitor's On Screen Display can more easily be accessed using this application.

ddcui normally communicates with the monitor using the DDC/CI protocol on a /dev/i2c device exposed by the video driver.

Alternatively, ddcui supports monitors that use USB for VCP communication.

The corresponding command line program is ddcutil.