D 2014-02-02T19:08:52.986 L Dithering P 4593f1415afac74be5e2e00fecb415b3f3188e6f U user W 502

Dithering

Dithering is the algorithm for preparing of image to black-white printing (old newspapers, old books) or for old displays systems. Here is 2 different implementations: general purpose with using of matrixes defined in imsh.scm library and special dithering algorithms.
Original image:

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Output image for general Sierra:

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