Space Filling Curve Dither with Adaptive Clustering
نویسندگان
چکیده
In this paper we investigate the problem of varying the size of dots in digital halftoning processes. We show that the dot size is the main factor determining the trade-oo between tonal and spatial resolution in the reproduction of gray scale images. We discuss the control of pixel aggregation in the context of dithering algorithms. In particular, we extend the dither with space lling curves method, introduced in (Velho & Gomes, 1991), to change the size of pixel clusters according to local characteristics of the image. This makes possible to achieve optimal rendition of gray shades while preserving image details.
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