1. A method operable on a computer that is coupled to a memory containing video data of a prescribed physical area, the method responsive to the movement of objects in the prescribed physical area, the method comprising: identifying objects in the prescribed physical area by querying the video data, wherein the objects that are identified are moving in the prescribed physical area; specifying by a user, a direction arrow completely within the prescribed physical area, wherein the direction arrow is superimposed on a user-selected portion of an image of the prescribed physical area; determining a number of objects that move in a direction of the specified direction arrow; and generating a visually perceptible output of the number of objects that move in the direction of the specified direction arrow, such that a movement path of each of the respective numbers of objects is superimposed on the user-selected portion of the image of the prescribed physical area.