vfeedback - Simulates video feedback.

       Jamie Zawinski.

X Version 11                                   6.08 (10-Oct-2023)                                  vfeedback(6x)

       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.

       Simulates video feedback: pointing a video camera at an NTSC television.

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.

       XSCREENSAVER_WINDOW
               The window ID to use with --root.

       vfeedback - Simulates video feedback.

--visualvisual
               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.

       --window-idnumber
               Draw on the specified window.

       --tv-colornumber
               Color Knob.  0 - 1000.   Default: 70.

       --tv-tintnumber
               Tint Knob.  0 - 100.  Default: 5.

       --noisenumber
               Analog noise.  0.0 - 0.2.  Default: 0.02.

       --darkennumber
               Darken the looped image. 0.0 - 1.0.  Default: 0.7.

       --tv-brightnessnumber
               Brightness Knob.  0.0 - 100.0.     Default: 3.0.

       --tv-contrastnumber
               Contrast Knob. 0 - 1500.  Default: 1000.

       --fps|--no-fps
               Whether to show a frames-per-second display at the bottom of the screen.

X(1), xscreensaver(1)

vfeedback  [--display  host:display.screen]  [--visual  visual]  [--window] [--root] [--window-id number]
       [--tv-color number] [--tv-tint number] [--noise number] [--tv-brightness number]  [--tv-contrast  number]
       [--fps]