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Stereogram Tutorial (2020)
Julio M. Otuyama Stereograms are illusions of 3D surfaces.
To create a SIRDS, you have to put not two, but a repeating pattern of random dots, and make shifts to get the desired effect. Sometimes the same pattern is copied many times at very close pixels, creating an (undesirable) visual clue of the hidden surface. With a general grayscale disparity map, the shift can be small or big, based on how black or white the gray tone is.
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