Patent ID: 7151996

Claim:
Apparatus for monitoring motion of a vehicle relative to a road on which the vehicle is traveling, comprising: a camera that acquires an image of a scene in which the road is present; and a controller that a) defines a plurality of real-space curves having different shapes and/or orientations that are candidates for substantially lying along a contour of the road; b) for each candidate curve, for each of a plurality of lines of pixels in the image that image regions of the scene lying along the candidate curve or that image regions of the scene lying along a same curve homologous with and having a same orientation as the candidate curve, determines a value that is a function of gradients of pixel intensities at locations along the line; c) determines a candidate curve that most closely lies along the road contour responsive to the values determined for the lines; and d) uses the determined candidate curve to monitor motion of the vehicle relative to the road.