Error-diffusion with output-dependent feedback (Fig. 1) is an adaptive halftoning algorithm that creates green-noise – binary dither patterns composed of homogeneously distributed minority pixel clusters. Using a single hysteresis parameter h, error-diffusion with output-dependent feedback is a tunable scheme which can regulate the average size of clusters according to the reliability of the printing device.

In this project, we intend to measure the relationships, for a given device, between h and the resulting tone reproduction and detail rendition of the printed image; furthermore, we will examine the relationships between the hysteresis parameter and the filter coefficients ai and bj. This research will provide the foundation for an inter-active device driver that allows the user to control the resulting coarseness of the printed image.

Project Goals:

  • For a given printing device, establish optimal relationships between the hysteresis parameter, the hysteresis coefficients, and the error-diffusion coefficients.

  • Develop an inter-active device driver that allows the user to specify a desired coarseness through a slider control.

Dr. Daniel Leo Lau
Department of Electrical and Computer Engineering
University of Kentucky
453 Anderson Hall
Lexington, KY 40506-0046, USA
(859) 257-2300 x273

last edited on 11/30/01