Occlusion Handling for Object Tracking Using a Fast Level Set Method

Tracking objects in image sequences is a difficult problem because of the frequent occlusions encountered among the objects and people. In this paper, a method for tracking objects through occlusions based on a level set technique, is presented. Two ca.ses are considered: 1-the object is obstructed by another one of a different color. 2-the object is obstructed by another one of the same color.In the first case, the classical algorithms based on active contours fail to track the object´s contour because the curve disappears from the scene. In this proposal, occlusion is detected and the solution is based on keeping the curve in the same place until the object of interest appears in the scene again.In the second case, the classic algorithms based on active contours do not distinguish between two image objects of the same color, so due to the possible changes in the topology, the curve fits the edge of both objects and it is divided. We solve this problem by means of localizing the centroid of the curve.The experimental results show that these methods significantly improve the tracking with occlusions.