A dual active contour for head boundary extraction

This paper presents a new approach to improve robustness of face contour extraction by extending active contour techniques. The main problems with the original snake technique include sensitivity to initialisation and obstruction of evolution by insignificant localised features. In deployment, these factors can force selection of an initial contour which is close to the target. By combining an expanding contour with a shrinking one, in a dual active contour, we can reduce sensitivity to initialisation, effectively by constraining the space in which the target contour is expected to lie.