1. A method of tracking entities using a single overhead camera comprising the steps of: detecting a foreground region in a video frame of the single overhead camera corresponding to one or more entities; determining if the foreground region is associated with an existing tracker; determining whether the detected foreground region is the result of at least one of a merger of two or more smaller foreground regions having corresponding existing trackers and a split of a larger foreground region having a corresponding existing tracker when the detected foreground region is not associated with an existing tracker; and tracking the detected foreground region via at least one existing tracker when the foreground region is at least one of associated with an existing tracker and the result of at least one of a merger and a split.