Ziplock Snakes

Abstract

We propose a snake-based approach that lets a user specify only the distant endpoints of the curve he wishes to delineate without having to supply an almost complete polygonal approximation. We greatly simplify the initialization process and achieve much better convergence properties than those of traditional snakes by using the image information around these endpoints to provide boundary conditions and by introducing an optimization schedule that allows a snake to take image information into account first only near its extremities and then, progressively, toward its center. In effect, the snakes are clamped onto the image contour in a manner reminiscent of a ziplock being closed.

These snakes can be used to alleviate the often repetitive task practitioners face when segmenting images by abolishing the need to sketch a feature of interest in its entirety, that is, to perform a painstaking, almost complete, manual segmentation.