Install xvattr by entering the following commands in the terminal:
sudo apt update sudo apt install xvattr
Description:
Utility to change Xv attributes
This is a small command line program to change Xv attributes like brightness, contrast,... . This package also include a gtk front-end.
Homepage: http://freecode.com/projects/xvattr
Version: 1.3-0.6ubuntu1
Section: universe/x11