Regular Articles

Alpha stable modeling of human visual systems for digital halftoning in rectangular and hexagonal grids

[+] Author Affiliations
Alvaro J. González

University of Delaware, Department of Electrical and Computer Engineering, Newark, Delaware

Jan Bacca Rodríguez

University of Delaware, Department of Electrical and Computer Engineering, Newark, Delaware

Gonzalo R. Arce

University of Delaware, Department of Electrical and Computer Engineering, Newark, Delaware

Daniel L. Lau

University of Kentucky, Department of Electrical and Computer Engineering, Lexington, Kentucky

J. Electron. Imaging. 17(1), 013004 (March 21, 2008). doi:10.1117/1.2898122
History: Received February 25, 2006; Revised September 25, 2007; Accepted September 26, 2007; Published March 21, 2008
Text Size: A A A

Human visual system (HVS) modeling has become a critical component in the design of digital halftoning algorithms. Methods that exploit the characteristics of the HVS include the direct binary search (DBS) and optimized tone-dependent halftoning approaches. The spatial sensitivity of the HVS is low-pass in nature, reflecting the physiological characteristics of the eye. Several HVS models have been proposed in the literature, among them, the broadly used Näsänen’s exponential model, which was later shown to be constrained in shape. Richer models are needed to attain better halftone attributes and to control the appearance of undesired patterns. As an alternative, models based on the mixture of bivariate Gaussian density functions have been proposed. The mathematical characteristics of the HVS model thus play a key role in the synthesis of model-based halftoning. In this work, alpha stable functions, an elegant class of functions richer than mixed Gaussians, are exploited to design HVS models to be used in two different contexts: monochrome halftoning over rectangular and hexagonal sampling grids. In the two scenarios, alpha stable models prove to be more efficient than Gaussian mixtures, as they use less parameters to characterize the tails and bandwidth of the model. It is shown that a decrease in the model’s bandwidth leads to homogeneous halftone patterns, and conversely, models with heavier tails yield smoother textures. These characteristics, added to their simplicity, make alpha stable models a powerful tool for HVS characterization.

Figures in this Article
© 2008 SPIE and IS&T

Topics

Halftones ; Modeling

Citation

Alvaro J. González ; Jan Bacca Rodríguez ; Gonzalo R. Arce and Daniel L. Lau
"Alpha stable modeling of human visual systems for digital halftoning in rectangular and hexagonal grids", J. Electron. Imaging. 17(1), 013004 (March 21, 2008). ; http://dx.doi.org/10.1117/1.2898122


Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections

PubMed Articles
Advertisement
  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.