Utilization of RVSI concept to evaluate the color constancy in photographic images

Abstract

The color constancy is an important property of the human visual system to recognize objects properly. It was said that the color constancy did not take place in photographic images, but the recognized visual space of illumination RVSI theory predicted the color constancy to take place in photographic images if the images could be perceived as three dimensional scenes. A D-up viewer was constructed with which a photograph can be perceived as a 3D scene in the first experiment and it was shown that the color constancy in the photograph took place as for the real space. The matching technique of color impression of a real room and that of a photographic image was successively used to achieve the experiment. While one eye was used in the D-up viewer, two eyes were used in the second experiment where a stereoscope was employed. It was proved that the color constancy also took place in photographic images. In the third experiment the state of color adaptation of subjects was investigated by measuring the color appearance of an achromatic stimulus patch inserted in a photograph. The color appeared very vivid in spite of the fact that the stimulus was achromatic when the photographs were prepared under vivid orange or blue illumination. The color adaptation of the visual system in photographic images was confirmed. General discussion was made for three experimental results and it was concluded that the color constancy could take place in photographic images.