Instead of perturbing each pixel in the input image at random, we can choose to dither by a predetermined amount depending on the pixel’s position in the image. This can be achieved using a threshold map; a small, fixed-size matrix where each entry tells us the amount by which to perturb the input value , producing the dithered value . This matrix is tiled across the input image and sampled for every pixel during the dithering process. The following describes a dithering function for a 4×4 matrix given the pixel raster coordinates :
Article InformationAuthor, 本·哈頓（Ben Hatton），这一点在爱思助手下载最新版本中也有详细论述
据《中国地中海贫血蓝皮书》（2020），“地中海贫血”是一种遗传性血液疾病，因曾高发于地中海沿岸国家而得名，在我国主要分布于长江以南的广东、广西、海南、福建、云南、贵州、四川、湖南、江西、重庆10个省（自治区、直辖市）。，详情可参考51吃瓜
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