Provided by: xscreensaver-data-extra_5.45+dfsg1-2ubuntu1_amd64 

NAME
vfeedback - Simulates video feedback.
SYNOPSIS
vfeedback [-display host:display.screen] [-visual visual] [-window] [-root] [-tv-color number] [-tv-tint
number] [-noise number] [-tv-brightness number] [-tv-contrast number] [-fps]
DESCRIPTION
Simulates video feedback: pointing a video camera at an NTSC television.
OPTIONS
-visual visual
Specify which visual to use. Legal values are the name of a visual class, or the id number
(decimal or hex) of a specific visual.
-window Draw on a newly-created window. This is the default.
-root Draw on the root window.
-tv-color number
Color Knob. 0 - 1000. Default: 70.
-tv-tint number
Tint Knob. 0 - 100. Default: 5.
-noise number
Analog noise. 0.0 - 0.2. Default: 0.02.
-darken number
Darken the looped image. 0.0 - 1.0. Default: 0.7.
-tv-brightness number
Brightness Knob. 0.0 - 100.0. Default: 3.0.
-tv-contrast number
Contrast Knob. 0 - 1500. Default: 1000.
-fps | -no-fps
Whether to show a frames-per-second display at the bottom of the screen.
ENVIRONMENT
DISPLAY to get the default host and display number.
XENVIRONMENT
to get the name of a resource file that overrides the global resources stored in the
RESOURCE_MANAGER property.
SEE ALSO
X(1), xscreensaver(1)
COPYRIGHT
Copyright © 2018 by Jamie Zawinski. Permission to use, copy, modify, distribute, and sell this software
and its documentation for any purpose is hereby granted without fee, provided that the above copyright
notice appear in all copies and that both that copyright notice and this permission notice appear in
supporting documentation. No representations are made about the suitability of this software for any
purpose. It is provided "as is" without express or implied warranty.
AUTHOR
Jamie Zawinski.
X Version 11 5.45 (08-Dec-2020) vfeedback(6x)