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

摘要

The test mask T_M 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 T_M in the case of chamfer norms. We characterize T_M 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 T_M.