Route search method by normalized cost

In this paper, we propose a method for extracting an object region from an image. First, we investigate the properties of the Intelligent Scissors (IS) method, which has been proposed as a method for extracting contours. As a result, we verify that the IS method’s route search according to total cost requires multiple seed points to extract a complex contour. Next, we show that this problem can be resolved by using the route length to normalize the total cost and then minimizing the normalized cost. Based on this principle, we propose a contour extraction method based on the normalized cost, which we term the Normalized Cost (NC) method. In addition, we construct a user interface that includes the NC method and perform quantitative comparison experiments. From the experiments comparing the NC method with the IS method, we verify that the NC method can extract a region faster and with fewer seed points than the IS method. We use these results to show the effectiveness of the proposed technique. © 2005 Wiley Periodicals, Inc. Syst Comp Jpn, 36(14): 11–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20420