Photo by Chris Ried on Unsplash

For some tasks like writing I prefer to have my displays set to monochrome / grayscale. This is how I do it on Xubuntu / XFCE.

There are several solutions out there that use xrandr or ddcutil but none of them worked for me. I'm using Xubuntu 22.04.2 LTS on a late 2012 Mac mini for some tasks.

So here is how you would do it using xrandr:

xrandr --output HDMI-3 --set Saturation 0

HDMI-3 is the name of my display.

You can get the name of your display by running xrandr without any arguments.

Connected displays will be listed like this:

HDMI-3 connected 1920x1200+1920+0 (normal left inverted right x axis y axis) 518mm x 324mm

The solution that actually worked for me was to use libvibrant and its source can be found on GitHub.

It's said to be build and installed this way:

mkdir build
cd build
cmake ..
make
sudo make install

However, I had to do few more things to get it working:

mkdir build
cd build

# fixes: Could not find X11
sudo apt install libx11-dev 

# fixes: The RandR library and headers were not found
sudo apt install xorg-dev libglu1-mesa-dev

# fixes: fatal error: NVCtrl/NVCtrlLib.h: No such file or directory
sudo apt install libxnvctrl-dev

cmake ..
make

# fixes: libvibrant.so.1 cannot open shared object file
sudo /sbin/ldconfig -v*

sudo make install

After that I was able to run vibrant-cli and it worked like a charm:

vibrant-cli HDMI-3 0
vibrant-cli DP-1 0

To reset the saturation to 100%:

vibrant-cli HDMI-3 1
vibrant-cli DP-1 1

Running this will make it look even better:

xgamma -gamma 0.8

If you create a .desktop entry for both commands, you easily run them using a launcher like Albert: