Medial Spheres for Shape Approximation

  • Svetlana Stolpner
  • Paul Kry
  • Kaleem Siddiqi
Conference paper
Part of the Advances in Intelligent and Soft Computing book series (AINSC, volume 83)


We study the problem of approximating a solid with a union of overlapping spheres. We introduce a method based on medial spheres which, when compared to a state-of-the-art approach, offers more than an order of magnitude speed-up and achieves a tighter volumetric approximation of the original mesh, while using fewer spheres. The spheres generated by our method are internal to the object, which permits an exact error analysis and comparison with other sphere approximations. We demonstrate that a tight bounding volume hierarchy of our set of spheres may be constructed using rectangle-swept spheres as bounding volumes. Further, once our spheres are dilated, we show that this hierarchy generally offers superior performance in approximate separation distance tests.


Voronoi Diagram Object Boundary Medial Surface Medial Axis Voronoi Cell 
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 2010

Authors and Affiliations

  • Svetlana Stolpner
    • 1
  • Paul Kry
    • 1
  • Kaleem Siddiqi
    • 1
  1. 1.School of Computer Science and Centre for Intelligent MachinesMontréalCanada

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