vfeedback(6x) on Linux
The text f828b91f62b7, as Debian 10 (Buster) shipped it.
Simulates video feedback.
Flags it lists
-
-darken -
-fps -
-no-fps -
-noise -
-root -
-tv-brightness -
-tv-color -
-tv-contrast -
-tv-tint -
-visual -
-window