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A Straight Skeleton Approximating the Medial Axis

  • Mirela Tănase
  • Remco C. Veltkamp
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3221)

Abstract

We propose the linear axis, a new skeleton for polygonal shapes. It is related to the medial axis and the straight skeleton, being the result of a wavefront propagation process. The wavefront is linear and propagates by translating edges at constant speed. The initial wavefront is an altered version of the original polygon: zero-length edges are added at reflex vertices. The linear axis is a subset of the straight skeleton of the altered polygon. In this way, the counter-intuitive effects in the straight skeleton caused by sharp reflex vertices are alleviated. We introduce the notion of ε-equivalence between two skeletons, and give an algorithm that computes the number of zero-length edges for each reflex vertex which yield a linear axis ε-equivalent to the medial axis. This linear axis and thus the straight skeleton can be computed from the medial axis in linear time for polygons with a constant number of “nearly co-circular” sites. All previous algorithms for straight skeleton computation are sub-quadratic.

Keywords

Voronoi Diagram Medial Axis Voronoi Cell Simple Polygon Linear Axis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Mirela Tănase
    • 1
  • Remco C. Veltkamp
    • 1
  1. 1.Institute of Information & Computing SciencesUtrecht UniversityThe Netherlands

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