1. An automatic headlamp control system for controlling the beam illumination state of at least one headlamp of a vehicle, said automatic headlamp control system comprising: at least one headlamp of the controlled vehicle, said at least one headlamp being operable to at least occasionally emit a light output having at least one of a signature, a code and a pattern superimposed thereon; an image sensor having a field of view forwardly of the vehicle, said image sensor being operable to capture an image of a scene forwardly of the vehicle; a control operable to process said image to identify at least one light source within the field of view of said image sensor and to determine if the detected at least one light source is indicative of at least one headlamp of an approaching vehicle or at least one taillight of a leading vehicle, said control being at least occasionally operable to process said image to distinguish a reflection of said light output as captured in said image via recognition of said at least one of a signature, a code and a pattern superimposed on said light output, said control being operable to adjust the beam illumination state of said at least one headlamp between a high beam state and a lower beam state in response to said image processing.