1glitchpeg(6x) XScreenSaver manual glitchpeg(6x)
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6 glitchpeg - glitched image screen saver.
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9 glitchpeg [--display host:display.screen] [--visual visual] [--window]
10 [--root] [--window-id number] [--delay number] [--duration number]
11 [--count number]
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14 Loads an image, corrupts it, and then displays the corrupted version,
15 several times a second. After a while, finds a new image to corrupt.
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17 It glitches the image by altering random bytes in the compressed image
18 file before de-compressing it. This creates interesting visual effects
19 on JPEG files, but doesn't work well on PNG files, since PNG contains
20 checksums that detect simple corruption.
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23 --visual visual
24 Specify which visual to use. Legal values are the name of a
25 visual class, or the id number (decimal or hex) of a specific
26 visual.
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28 --window
29 Draw on a newly-created window. This is the default.
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31 --root Draw on the root window.
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33 --window-id number
34 Draw on the specified window.
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36 --delay number
37 Per-frame delay, in microseconds. Default: 30000 (0.03 sec‐
38 onds).
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40 --duration number
41 How many seconds before loading a new image. Default: 120.
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43 --count number
44 Number of glitches to introduce per iteration. Default: 400.
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47 DISPLAY to get the default host and display number.
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49 XENVIRONMENT
50 to get the name of a resource file that overrides the global
51 resources stored in the RESOURCE_MANAGER property.
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53 XSCREENSAVER_WINDOW
54 The window ID to use with --root.
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57 Because this program is feeding intentionally-invalid data into your
58 operating system's image-decoding libraries, it is possible that it may
59 crash as a result of that corrupted data.
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61 That should not be possible -- but it might be.
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63 Please note that if this happens, that indicates a serious security bug
64 in your system's image libraries! It likely means that your libraries
65 are susceptible to buffer overflow attacks or similar, which can lead
66 to remote code execution. You should report that bug to the maintain‐
67 ers of those image libraries.
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69 In the context of xscreensaver, when configured to load only local im‐
70 age files, this should not be a direct security concern: this screen
71 saver crashing will not affect the xscreensaver daemon and will not un‐
72 lock your screen.
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75 X(1), xscreensaver(1)
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78 Copyright © 2018 by Jamie Zawinski. Permission to use, copy, modify,
79 distribute, and sell this software and its documentation for any pur‐
80 pose is hereby granted without fee, provided that the above copyright
81 notice appear in all copies and that both that copyright notice and
82 this permission notice appear in supporting documentation. No repre‐
83 sentations are made about the suitability of this software for any pur‐
84 pose. It is provided "as is" without express or implied warranty.
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87 Jamie Zawinski.
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91X Version 11 6.06-1.fc37 (12-Dec-2022) glitchpeg(6x)