Above: contours used for the EB score. In green: inter- nal contours, in blue: intersecting contours and in red: external contours. From (a) to (d): the EB score decreases (the number of internal contours decreases and the number of traversing contours increases). Below: the additional contours used for the CAO score. In pink: affiliated external contours. In (e) and (f): as the number of affiliated external contours increases the CAO score decreases.