A corneal-reflection-based gaze detection section (28) calculates a time series of a three-dimensional gaze vector in a camera coordinate system from a time series of facial images. A face position-and-orientation estimation section (24) estimates a time series of a three-dimensional position and orientation of a face. An eyeball-center-coordinates transformation section (32) calculates a time series of a three-dimensional position of the eyeball center in a coordinate system of a three-dimensional facial model. A fixed parameter calculation section (33) calculates for use as a fixed parameter a three-dimensional position of the eyeball center in the three-dimensional facial-model coordinate system. An eyeball-center-based gaze detection section (36) uses the three-dimensional position of the eyeball center calculated by the fixed parameter calculation section (33) to calculate a three-dimensional gaze vector from a three-dimensional position of the eyeball center to a three-dimensional position of a pupil center in the camera coordinate system. This enables accurate gaze tracking to be performed using a simple configuration and without performing calibration.
GAZE-TRACKING DEVICE, PROGRAM, AND METHOD