Using Infrared Images of a Monitored Scene to Identify Windows

A non-transitory computer readable storage medium storing one or more programs configured for execution by a camera system having a memory configured to store information, a lens assembly arranged to direct light from a scene onto an image sensing element, an image sensing element configured to receive light from the scene via the lens assembly, at least one infrared illuminator configured to transmit infrared light, and a processor, coupled to the image sensing element and the at least one infrared illuminator, wherein the one or more programs comprise instructions for:

• operating the at least one infrared illuminator and the image sensing element in a first mode whereby infrared light transmitted by the at least one infrared illuminator and reflected from the scene is used to generate a two-dimensional image of the scene;
• and
• operating the at least one infrared illuminator and the image sensing element in a second mode whereby infrared light transmitted by the at least one infrared illuminator and reflected from the scene is used to detect a first region, located within the scene, having a specific material.