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arXiv · 2203.05715

Unitary rotation of pixellated polychromatic images

Alejandro R. Urzúa·Kurt Bernardo Wolf
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Abstract

Unitary rotations of polychromatic images on finite two-dimensional pixellated screens provide invertibility, group composition, and thus conservation of information. Rotations have been applied on monochromatic image data sets, where we now examine closer the Gibbs-like oscillations that appear due to discrete "discontinuities" of the input images under unitary transformations. Extended to three-color images we examine here the display of color at the pixels where, due to the oscillations, some pixel color values may fall outside their required common numerical range [0, 1], between absence and saturation of the red, green, and blue formant color images.

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Alejandro R. Urzúa, Kurt Bernardo Wolf. 2022-03-11. Unitary rotation of pixellated polychromatic images. https://doi.org/10.1364/josaa.462530

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