Medial axis lookup table and test neighborhood computation for 3D chamfer norms

Medial Axis LUT Computation for Chamfer Norms Using H-Polytopes

Chamfer distances are discrete distances based on the propagation of local distances, or weights defined in a mask. The medial axis, i.e. the centers of the maximal disks (disks which are not contained in any other disk), is a powerful tool for shape representation and analysis. The extraction of maximal disks is performed in the general case with comparison tests involving look-up tables repre...

2D Subquadratic Separable Distance Transformation for Path-Based Norms

In many applications, separable algorithms have demonstrated their efficiency to perform high performance and parallel volumetric computations, such as distance transformation or medial axis extraction. In the literature, several authors have discussed about conditions on the metric to be considered in a separable approach. In this article, we present generic separable algorithms to efficiently...

Appearance Radii in Medial Axis Test Mask for Small Planar Chamfer Norms

The test mask TM is the minimum neighbourhood sufficient to extract the medial axis of any discrete shape, for a given chamfer distance mask M. We propose an arithmetical framework to study TM in the case of chamfer norms. We characterize TM for 3×3 and 5×5 chamfer norm masks, and we give an algorithm to compute the appearance radius of the vector (2, 1) in TM.

Computing 3D Medial Axis for Chamfer Distances

Chordal Axis on Weighted Distance Transforms

Chordal Axis (CA) is a new representation of planar shapes introduced by Prasad in [7], useful for skeleton computation, shape analysis, characterization and recognition. The CA is a subset of chord and center of disks 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 tria...