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        Autostereogram Tutorial Clean Background
        
         - Description: This is an example of a wallpaper with repeated horizontal patterns. Each pattern is repeated exactly every 140 pixels. The illusion of a plane (flat surface) created by the brain lies behind the wall. However, non-repeating patterns such as the arrows and words appear on the same plane where this text lies.
 
        
        
         - Source: Fred Hsu, March 2005.
 
        
        
         
        
        
         
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          Permission is granted to copy, distribute and/or modify this document under the terms of the  GNU Free Documentation License, Version 1.2 or any later version published by the  Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled  GNU Free Documentation License.  http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue 
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