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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] [-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 (C) 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		      5.44 (20-Mar-2020)		  glitchpeg(6)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ENVIRONMENT | SECURITY | SEE ALSO | COPYRIGHT | AUTHOR

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