1. A method for determining whether a front passenger seat is occupied in an image of a motor vehicle traveling in a High Occupancy Vehicle (HOV) lane, the method comprising: receiving an image of a motor vehicle which is intended to be analyzed for seat occupancy; clipping said image to a windshield area; identifying features of a front passenger seat and associated headrest in a front passenger compartment of said motor vehicle where a passenger would be seated, comprising: performing edge detection on said windshield area of said clipped image to locate vertical, horizontal, and curved lines comprising edge segments of said seat and associated headrest; determining whether said lines are substantially contiguous; and determining whether an area bounded by said edge segments is substantially uniform or non-uniform; and in response to said edge segments being substantially contiguous and said bounded area being substantially uniform, determining from said seat features whether said front passenger seat is occupied.