Closed dynamic contour models that split and merge

Classical dynamic contours (snakes) suffer from their inability to properly address the crossover problem. In the closed contour case, a part of the snake inverts and expands without bounds. This paper proposes a novel approach to handle inversions by splitting the contour at the points of self-intersection. Separated parts that are inverted are destroyed while the remaining parts are used to seed new snakes. Collisions of snakes cause them to merge. The probability of crossovers is further reduced by an efficient reparameterization procedure. The method is successfully applied to the challenging task of tracking the globule in a motion lamp.