Error-diffusion with output-dependent feedback 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, but as a constant, h sacrifices an unnecessary amount of edge detail.

In this project, we study the introduction of an adaptive hysteresis parameter which varies according to the local frequency content within the image, leading to a halftoned image with better edge details. The goal of this work is to establish an optimal relationship between h and the frequency content of the input image for a given printing device.

Project Goals:

  • Establish relationship between the hysteresis parameter, the local edge content of the input image, and the detail rendition in the printing image.

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