1. A method for detecting sitting behavior, the method comprising: acquiring a sequence of frames capturing a scene-of-interest at an overhead view; detecting at least one empty seat within the scene-of-interest and associating the seat as being unoccupied and the frame as a reference frame; extracting reference features describing a region of the unoccupied seat in the reference frame and quantifying the reference features to form a reference feature vector; extracting features describing the region in a given frame and quantifying the features to form a current feature vector; measuring a change in a feature vector over time using the reference feature vector and the current feature vector; and, determining a status of the seat in the given frame as being one of occupied and unoccupied based on the change in the feature vector.