A Discrete lambda-Medial Axis

John Chaussard, Michel Couprie, Hugues Talbot

Abstract: The λ-medial axis was introduced in 2005 by Chazal and Lieutier as a new concept for computing the medial axis of a shape subject to filtering with a single parameter. These authors proved the stability of the λ-medial axis under small shape perturbations. In this paper, we introduce the definition of a discrete λ-medial axis (DLMA). We evaluate its stability and rotation invariance experimentally. The DLMA may be computed by efficient algorithms, furthermore we introduce a variant of the DLMA, denoted by DL’MA, which may be computed in linear-time. We compare the DLMA and the DL’MA with the recently introduced integer medial axis and show that both DLMA and DL’MA provide measurably better results.