Forced random dithering: improved threshold matrices for ordered dithering

Abstract

This paper examines the possibilities of improving halftoning techniques using dispersed dots. This corresponds to finding micro-dot distributions that approximate the intensity levels that have to be rendered. A widely used halftoning method is ordered dithering, which uses a threshold matrix to decide if a micro-dot should be set in the output image. A way to generate improved threshold matrices for ordered dithering will be introduced that avoids unwanted low-frequency portions without introducing too much random noise into the rendered image. Since the presented method produces images of high quality it is ideally suited for output generation in high-end image processing systems. >