Skip to content


  • Research Article
  • Open Access

Design of Farthest-Point Masks for Image Halftoning

EURASIP Journal on Advances in Signal Processing20042004:143458

  • Received: 3 September 2003
  • Published:


In an earlier paper, we briefly presented a new halftoning algorithm called farthest-point halftoning. In the present paper, this method is analyzed in detail, and a novel dispersion measure is defined to improve the simplicity and flexibility of the result. This new stochastic screen algorithm is loosely based on Kang's dispersed-dot ordered dither halftone array construction technique used as part of his microcluster halftoning method. Our new halftoning algorithm uses pixelwise measures of dispersion based on one proposed by Kang which is here modified to be more effective. In addition, our method exploits the concept of farthest-point sampling (FPS), introduced as a progressive irregular sampling method by Eldar et al. but uses a more efficient implementation of FPS in the construction of the dot profiles. The technique we propose is compared to other state-of-the-art dither-based halftoning methods in both qualitative and quantitative manners.

Keywords and phrases

  • image halftoning
  • ordered dither
  • irregular sampling
  • halftoning quality measures

Authors’ Affiliations

Electrical & Computer Engineering, Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John's, NL, A1B 3X5, Canada
Image Processing Laboratory, DEEI, University of Trieste, Trieste, 34127, Italy


© Shahidi et al. 2004