1. A method of analyzing a depth image in a digital system, the method comprising: detecting a foreground object in a depth image, wherein the depth image is a top-down perspective of a scene; and performing data extraction and classification on the foreground object using depth information in the depth image; computing a height of the foreground object based on a height of a depth camera used to capture the depth image; and classifying the foreground object based on the computed height and a 2D shape of the foreground object.