1glitchpeg(6x)                 XScreenSaver manual                glitchpeg(6x)
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NAME

6       glitchpeg - glitched image screen saver.
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SYNOPSIS

9       glitchpeg  [-display  host:display.screen]  [-visual  visual] [-window]
10       [-root] [-delay number] [-duration number] [-count number]
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DESCRIPTION

13       Loads an image, corrupts it, and then displays the  corrupted  version,
14       several times a second. After a while, finds a new image to corrupt.
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16       It  glitches the image by altering random bytes in the compressed image
17       file before de-compressing it. This creates interesting visual  effects
18       on  JPEG  files, but doesn't work well on PNG files, since PNG contains
19       checksums that detect simple corruption.
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OPTIONS

22       -visual visual
23               Specify which visual to use.  Legal values are the  name  of  a
24               visual  class,  or the id number (decimal or hex) of a specific
25               visual.
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27       -window Draw on a newly-created window.  This is the default.
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29       -root   Draw on the root window.
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31       -delay number
32               Per-frame delay, in microseconds.  Default:  30000  (0.03  sec‐
33               onds).
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35       -duration number
36               How many seconds before loading a new image.  Default: 120.
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38       -count number
39               Number of glitches to introduce per iteration. Default: 100.
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ENVIRONMENT

42       DISPLAY to get the default host and display number.
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44       XENVIRONMENT
45               to  get  the  name of a resource file that overrides the global
46               resources stored in the RESOURCE_MANAGER property.
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SECURITY

49       Because this program is feeding intentionally-invalid  data  into  your
50       operating system's image-decoding libraries, it is possible that it may
51       crash as a result of that corrupted data.
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53       That should not be possible -- but it might be.
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55       Please note that if this happens, that indicates a serious security bug
56       in  your system's image libraries!  It likely means that your libraries
57       are susceptible to buffer overflow attacks or similar, which  can  lead
58       to  remote code execution.  You should report that bug to the maintain‐
59       ers of those image libraries.
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61       In the context of xscreensaver, when  configured  to  load  only  local
62       image  files, this should not be a direct security concern: this screen
63       saver crashing will not affect the xscreensaver  daemon  and  will  not
64       unlock your screen.
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SEE ALSO

67       X(1), xscreensaver(1)
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70       Copyright  ©  2018 by Jamie Zawinski.  Permission to use, copy, modify,
71       distribute, and sell this software and its documentation for  any  pur‐
72       pose  is  hereby granted without fee, provided that the above copyright
73       notice appear in all copies and that both  that  copyright  notice  and
74       this  permission  notice appear in supporting documentation.  No repre‐
75       sentations are made about the suitability of this software for any pur‐
76       pose.  It is provided "as is" without express or implied warranty.
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AUTHOR

79       Jamie Zawinski.
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83X Version 11               5.43-2.fc31 (27-Aug-2019)             glitchpeg(6x)
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