SMOOTHLY PERFECT 8-CONNECTED CONTOUR AND ITS CODING TECHNIQUE

평활한 완전 8방향 윤곽선과 이의 부호화 기법

In this paper, we introduce the notion of the smoothly perfect 8-connected (SP8C) contour and propose a coding technique for the SP8C contours. Based on the contour simplification using the majority filter proposed by Gu[6], SP8C contours are extracted on the contour lattice from the segmented image. By noting that, unlike the perfect 8-connected contours, the SP8C contours are restricted to travel in only 3 different directions along the contours, we also propose two techniques for encoding the SP8C contours. The one is the modified version of the neighbouring direction segment coding by Kandeko[2], while the other is to employ the notion of the entropy coding. From the comparison in terms of the entropy, it is shown that the proposed SP8C contours require les bits in encoding the diagonal contours than the 4-connected contours employed by Gu. And computer simulations reveal that the contours can be efficiently encoded by the proposed technique.