Noise-Resistant Affine Skeletons of Planar Curves

  • Santiago Betelu
  • Guillermo Sapiro
  • Allen Tannenbaum
  • Peter J. Giblin
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1842)


A new definition of affine invariant skeletons for shape representation is introduced. A point belongs to the affine skeleton if and only if it is equidistant from at least two points of the curve, with the distance being a minima and given by the areas between the curve and its corresponding chords. The skeleton is robust, eliminating the need for curve denoising. Previous approaches have used either the Euclidean or affine distances, thereby resulting in a much less robust computation. We propose a simple method to compute the skeleton and give examples with real images, and show that the proposed definition works also for noisy data. We also demonstrate how to use this method to detect affine skew symmetry.


Real Image Medial Axis Planar Curf Simple Closed Curve Euclidean Case 
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 2000

Authors and Affiliations

  • Santiago Betelu
    • 1
  • Guillermo Sapiro
    • 2
  • Allen Tannenbaum
    • 3
  • Peter J. Giblin
    • 4
  1. 1.Department of MathematicsUniversity of MinnesotaMinneapolis
  2. 2.Department of Electrical and Computer EngineeringUniversity of MinnesotaMinneapolis
  3. 3.Department of Electrical and Computer EngineeringGeorgia Institute of TechnologyAtlanta
  4. 4.Department of MathematicsU. of LiverpoolLiverpoolUK

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