1. An apparatus for monitoring movement of objects of interest in an area, the apparatus comprising: an activity map generation circuit configured to, generate a plurality of activity maps based on video content from a plurality of cameras, each of the plurality of activity maps being indicative of relative activity of the objects of interest over time within a field of view of a camera among the plurality of cameras, and each of the plurality of cameras having a different corresponding field of view in the area, and standardize the plurality of activity maps with regard to a single common point of view; a unified spatial activity map generation circuit configured to combine the plurality of standardized activity maps into a unified activity map; and wherein the activity map generation circuit is further configured to standardize the plurality of activity maps with regard to the single common point of view by at least one of modifying a direction feature with respect to tilt of at least one camera among the plurality of cameras, transforming a spatial perspective of at least one of the plurality of activity maps from image coordinates to coordinates corresponding to the single common point of view, normalizing an orientation of at least one of the plurality of activity maps, normalizing probabilities with respect to at least one of the plurality of cameras, and transforming a perspective spread of at least one of the plurality of activity maps.