Convex Shapes and Convergence Speed of Discrete Tangent Estimators

  • Jacques-Olivier Lachaud
  • François de Vieilleville
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4292)


Discrete geometric estimators aim at estimating geometric characteristics of a shape with only its digitization as input data. Such an estimator is multigrid convergent when its estimates tend toward the geometric characteristics of the shape as the digitization step h tends toward 0. This paper studies the multigrid convergence of tangent estimators based on maximal digital straight segment recognition. We show that such estimators are multigrid convergent for some family of convex shapes and that their speed of convergence is on average \({\mathcal{O}}{(h^{\frac{2}{3}})}\). Experiments confirm this result and suggest that the bound is tight.


Convergence Speed Tangent Direction Convex Shape Standard Line Grid Step 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Jacques-Olivier Lachaud
    • 1
  • François de Vieilleville
    • 1
  1. 1.LaBRIUniv. Bordeaux 1France

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