1. For use in a vehicle, an automated, computerized method for processing an image, comprising the steps of: receiving from a digital camera mounted on the vehicle, an image file depicting pixels of an image of a scene related to vehicle operation on a road, each one of the pixels having N band color values; generating an illumination-invariant image representation of the image based upon the N color bands of the pixels and as a function of a BIDR model; converting the illumination-invariant image representation to a grayscale image; and converting the grayscale image to an illumination-invariant color image wherein each pixel of the illumination-invariant color image is at an intensity set according to an intensity of a corresponding pixel of the grayscale image and having a color set to a color calculated as a function of the N color bands of a corresponding pixel of the image, adjusted to remove color shift caused by an interplay of incident and ambient illumination, according to the BIDR model.