Ellipse-reproducing snakes -- Variation on a theme
Dr Cédric Vonesch, EPFL STI LIB

Seminar • 20 August 2012 • BM 4.233

Abstract
Inspired by Delgado et al.'s work, we explore parametric representations of ellipses that are both minimal (i.e., involving 5 real parameters) and linear with respect to a fixed family of basis functions. We first show that it is impossible to obtain such a parametrization when the basis is constrained to be shift-invariant. As a work-around we construct a "shift-covariant" basis that does allow for a minimal and linear parametrization. By shift-covariant we mean that two elements of the basis are related through an integer shift and a multiplication by a complex number. Furthermore the basis elements are compactly supported and refinable. As a proof-of-concept we use this representation for constructing a 3D parametric model of a mitotic cell. Ultimately the goal is to create a model that can serve as phantom data for evaluating various image-processing algorithms in a biological context.