“…The most common method used for traffic signs detection is colour-segmentation. This method is based on the assumed fact that the wavelength coming from a sign, for instance the redcoloured edge of a speed-limit sign, does not change with changes in the intensity and the incidence-angle of the light onto the sign, if HSV or HIS spaces are used [4], [5]. The image of the camera is not, however, completely invariant under changes in the chromaticity of the received light, being these changes due to shades, adverse weather conditions, etc.…”