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Associated article: Extended Visual Cryptography Schemes

Tags: Security          Design    

Published source code accompanying the article by Daniel Stoleru in which he examines Extended Visual Cryptography Schemes--graphical forms of information concealing.

					Extended Visual Cryptography Schemes 
by Daniel Stoleru

Listing One

#dithering mask four-point star type
_starMask = ((40,  80, 140, 120,  20),
             (60, 170, 210, 190, 100),
             (150, 240, 250, 230, 160),
             (90, 200, 220, 180,  50),
             (10, 110, 130,  70,  30))
#dithering mask box type
_boxMask = ((138, 230,   5, 219, 107),
            (87,  46, 179,  67, 148),
            (189,  26, 250,  15, 199),
            (158,  77, 168,  56,  97),
            (128, 209,  36, 240, 117))

Listing Two

def encrypt(self, mask = _boxMask):
""" Perform the actual dithering algorithm. For any pixel in the 
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