Chordal Axis on Weighted Distance Transforms

  • Jérôme Hulin
  • Edouard Thiel
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4245)


Chordal Axis (CA) is a new representation of planar shapes introduced by Prasad in [1], useful for skeleton computation, shape analysis, characterization and recognition. The CA is a subset of chord and center of discs tangent to the contour of a shape, derivated from Medial Axis (MA). Originally presented in a computational geometry approach, the CA was extracted on a constrained Delaunay triangulation of a discretely sampled contour of a shape. Since discrete distance transformations allow to efficiently compute the center of distance balls and detect discrete MA, we propose in this paper to redefine the CA in the discrete space, to extract on distance transforms in the case of chamfer norms, for which the geometry of balls is well-known, and to compare with MA.


image analysis shape description chordal axis medial axis discrete geometry chamfer or weighted distances 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Jérôme Hulin
    • 1
  • Edouard Thiel
    • 1
  1. 1.Laboratoire d’Informatique Fondamentale de Marseille (LIF, UMR 6166)France

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