US Patent 9396400 Computer-vision based security system using a depth camera

A method for securing an environment. The method includes obtaining a two-dimensional (2D) representation of a three-dimensional (3D) environment. The 2D representation includes a 2D frame of pixels encoding depth values of the 3D environment. The method further includes identifying a set of foreground pixels in the 2D representation, defining a foreground object based on the set of foreground pixels. The method also includes classifying the foreground object, and taking an action based on the classification of the foreground object.