Combination of piecewise-geodesic curves for interactive image segmentation

Abstract

Boundary-based interactive image segmentation methods aim to build a closed contour, very often using paths linking a set of user-provided landmark points, ordered along the contour of the object of interest. Among these methods, the geodesically-linked active contour (GLAC) model generates a piecewise-geodesic curve, by linking each pair of successive landmark points by a geodesic curve. As an important shortcoming, the geodesically linked active contour model in its initial formulation does not guarantee the curve to be simple. It may have multiple points, creating self-tangencies and self-intersections, which is inconsistent with respect to the purpose of segmentation. To overcome this issue, we study some properties of non-simple closed curves and introduce a novel energy term to quantity the amount of non-simplicity. We propose to extract a relevant contour from a set of possible paths, such that the resulting structure fits the image data and is simple. We develop a local search method to choose the best combination among possible paths, integrating the novel energy term.