A discriminator (19) identifies windrow pixels associated with a windrow within a collected image. A definer (14) defines a search space with respect to a vehicle. An evaluator (19) determines respective spatial correlations between the defined search space and the windrow pixels for different angular displacements of the search space. An alignment detector (18) or search engine determining a desired vehicular heading as a preferential angular displacement associated with a generally maximum spatial correlation between the defined search space and the windrow pixels. An offset calculator (21) estimates an offset of the vehicle to a central point of the windrow or a depth axis to achieve the desired vehicle heading and desired position of the vehicle with respect to the windrow.
