template updating has been one of the most difficult problems in the object tracking algorithms based on pattern matching. Because both appearance changes and occlusions can lead to the changes in the intensity of object
however
changes that result from the obstacles can’t be updated as the template; while changes that result from the object in itself should be updated in time. Therefore
a local template update method with the discrimination between occlusions and appearance changes is presented in this paper. The proposed method uses the fragment template for the tracking and distinguishes occlusions from appearance changes according to the probabilities of which varied gray level information belongs to the target and to the background region. The template is preserved to prevent the information of the obstacles from contaminating the template when the target has been partially occluded; while a new adaptive local template update algorithm is used in the case of appearance changes. Experimental results are presented to demonstrate that our algorithm can be adaptive to the appearance changes as well as occlusions and is more robust than the total model update strategy.