Color and printer models for color halftoning

Two error diffusion algorithms, based on Pappas's printer model accounting for dot-overlapping and ink distortion, are presented to achieve good color reproduction. The basic idea is to combine printer and color models on the perceptually uniform Commission Internationale de l'Eclairge (CIE) L*a*b* (CIE 1976) color space. The models, derived from the Neugebauer equations and color matching theories, are designed to achieve the minimization of the human visual color distortions between the colors of original pixels and those of a halftoned image. The effectiveness of our approaches is shown by comparison and examination of two error diffusion algorithms with previous methods: the error diffusion based models and the window based minimization algorithm. Experimental results of the error clipping technique, focused on the real application of the nonseparable algorithm, and the desired range of error clipping, where an image produced by the nonseparable algorithm can be stable without additional color distortion are reported. (C) 1997 SPIE and IS&T. [S1017-9909(97)00102-5].