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glitchpeg(6)		       XScreenSaver manual		    glitchpeg(6)

NAME
     glitchpeg - glitched image screen saver.

SYNOPSIS
     glitchpeg	[--display  host:display.screen]  [--visual  visual]  [--window]
     [--root] [--window-id number] [--delay number] [--duration number] [--count
     number]

DESCRIPTION
     Loads an image, corrupts it, and then displays the corrupted version,  sev-
     eral 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.

     --window-id number
	     Draw on the specified window.

     --delay number
	     Per-frame delay, in microseconds.	Default: 30000 (0.03 seconds).

     --duration number
	     How many seconds before loading a new image.  Default: 120.

     --count number
	     Number of glitches to introduce per iteration. Default: 400.

ENVIRONMENT
     DISPLAY
	     to get the default host and display number.

     XENVIRONMENT
	     to  get  the  name of a resource file that overrides the global re-
	     sources stored in the RESOURCE_MANAGER property.

     XSCREENSAVER_WINDOW
	     The window ID to use with --root.

SECURITY
     Because this program is feeding intentionally-invalid data into your  oper-
     ating  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 maintainers of those im-
     age libraries.

     In the context of xscreensaver, when configured to load  only  local  image
     files,  this  should  not	be  a direct security concern: this screen saver
     crashing will not affect the xscreensaver daemon and will not  unlock  your
     screen.

SEE ALSO
     X(1), xscreensaver(1)

COPYRIGHT
     Copyright	(C)  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  no-
     tice 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		       6.15 (30-Mar-2026)		    glitchpeg(6)

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