A Two-Dimensional Spatial-based Wiener Printer Model Embedded Into Model- based Digital Halftoning

This paper presents a two-dimensional Wiener model in spatial domain for a class of laser electrophotographic printers, and embeds it into a framework of model-based digital halftoning. The Wiener model comprises an FIR filter followed by a nonlinear static mapping. The nonlinear static mapping is synthesized using a fuzzy system to maximize its capability to approximate nonlinearity of high degree. A set of systematic steps for parametric optimization and evaluation of the Wiener printer model is proposed. Due to the parameters being determined off-line, the Wiener model demands much less computation and memory when executing on-line. Another advantage is that the structure complexity of the Wiener model is adjustable via altering the order of the FIR filter and the number of membership functions in the fuzzy system. Experimental results as well as a comparative study show that the proposed model-based halftoning approach is superior (in terms of image quality) to conventional ones and comparable to the one with a comprehensive printer model.