Pupil diameter measurement in visible-light environment using separability filter

The various systems using the information of pupil diameter variation have been studied and developed. These systems are presupposed to be operated on a general-purpose PC or a portable terminal. To obtain the information of pupil diameter, a near-infrared camera and illuminations are required. However, the conventional PC or portable terminal does not have a near-infrared camera and illumination. If the pupil diameter can be measured by using the visible-light camera equipped in the general-purpose PC or the portable terminal, such systems using the information of pupil diameter variation can be widely used. It is difficult to discriminate between the iris and pupil regions in an image captured by the visible-light camera because the iris and pupil colors of Asian people are similar. In this paper, for the generalization of the systems using the information of pupil diameter variation, we proposed the measurement method of the pupil diameter from the image taken by the visible-light camera. From the experimental results, the accuracy of proposed method was equivalent to that of the conventional method of pupil diameter measurement using the near-infrared camera and the illumination.