Patent ID: 8810642

Claim:
A pupil detection apparatus comprising: a first imaging pair comprising an imager and a light-emitter that emits light at a time of imaging, the imager and the light-emitter being separated by a first predetermined separation distance; a second imaging pair comprising an imager and a light-emitter separated by a second predetermined separation distance, which is greater than the first predetermined separation distance of the first imaging pair; a detector that detects a first pupil image from a first person image in which a person is imaged by the first imaging pair, and detects a second pupil image from a second person image in which the person is imaged by the second imaging pair; an accuracy value calculator that calculates a first red-eye occurrence intensity, which is relative brightness of brightness within the first pupil image with respect to brightness of a peripheral image outside the first pupil image, and a second red-eye occurrence intensity, which is relative brightness of brightness within the second pupil image with respect to brightness of a peripheral image outside the second pupil image, and, based on a correlation characteristic between the calculated first and second red-eye occurrence intensities and a pupil detection accuracy value, calculates pupil detection accuracy values corresponding to the calculated first and second red-eye occurrence intensities; a selector that selectively outputs a detection result of the first pupil image or a detection result of the second pupil image based on a variation trend characteristic of the calculated pupil detection accuracy values; wherein the selector selects the detection result of the first pupil image when all the calculated pupil detection accuracy values in a predetermined period are less than a predetermined threshold value, and a time variation trend of the calculated pupil detection accuracy values is an unrelievedly decreasing variation trend characteristic; and wherein the predetermined threshold value is a pupil detection accuracy value corresponding to a point at which a first correlation characteristic between the calculated first red-eye occurrence intensity and a first pupil detection accuracy value of the first pupil image, and a second correlation characteristic between the calculated second red-eye occurrence intensity and a second pupil detection accuracy value of the second pupil image, intersect.