An Improved Live-Wire Freed from the Restriction of the Direct Line Between Seed Points

Abstract

In the original live-wire algorithm, optimality is defined as the minimum cumulative cost path from a seed point to another, where the cumulative cost of a path is the sum of the local edge costs on the path. Therefore, the optimal path between two seed points is restricted not far away from the straight line between these two points. Consequently, when delineating a boundary with acute concaves and convexes, more seed points are required which can become very time consuming to calculate. This paper proposed an improved live-wire algorithm where the optimality is redefined as the minimum average cost path between two seed points, which frees the optimal path from the restriction of the straight line. In theory, the original live-wire algorithm is only a special case of our improved algorithm. Furthermore, the Canny edges on the boundary of the target object is weighted according to the gray or color value of the seed point. Experiments conducted on a variety of image types have shown that this improved live-wire algorithm requires less seed points than the original algorithm when delineating the same boundary and as a result, reduces the time required to complete the calculation.