glitchpeg(6x) XScreenSaver manual glitchpeg(6x)
NAME
glitchpeg - glitched image screen saver.
SYNOPSIS
glitchpeg [-display host:display.screen] [-visual visual] [-window]
[-root] [-delay number] [-duration number] [-count number]
DESCRIPTION
Loads an image, corrupts it, and then displays the corrupted version,
several times a second. After a while, finds a new image to corrupt.
It glitches the image by altering random bytes in the compressed image
file before de-compressing it. This creates interesting visual effects
on JPEG files, but doesn't work well on PNG files, since PNG contains
checksums that detect simple corruption.
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.
-delay number
Per-frame delay, in microseconds. Default: 30000 (0.03 sec-
onds).
-duration number
How many seconds before loading a new image. Default: 120.
-count number
Number of glitches to introduce per iteration. Default: 100.
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.
SECURITY
Because this program is feeding intentionally-invalid data into your
operating system's image-decoding libraries, it is possible that it may
crash as a result of that corrupted data.
That should not be possible -- but it might be.
Please note that if this happens, that indicates a serious security bug
in your system's image libraries! It likely means that your libraries
are susceptible to buffer overflow attacks or similar, which can lead
to remote code execution. You should report that bug to the maintain-
ers of those image libraries.
In the context of xscreensaver, when configured to load only local im-
age files, this should not be a direct security concern: this screen
saver crashing will not affect the xscreensaver daemon and will not un-
lock your screen.
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 pur-
pose 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 repre-
sentations are made about the suitability of this software for any pur-
pose. It is provided "as is" without express or implied warranty.
AUTHOR
Jamie Zawinski.
X Version 11 5.45 (08-Dec-2020) glitchpeg(6x)
Generated by dwww version 1.14 on Sat Jun 13 12:41:41 CEST 2026.