1. A method for estimating a gaze target within a visual target that a person is looking based on automatic image measurements, comprising the following steps of: a) processing calibrations for at least a first means for capturing images for face-view and at least a second means for capturing images for top-down view, b) determining a target grid of the visual target, c) detecting and tracking a face of the person from first input images captured by the first means for capturing images, d) estimating a two-dimensional pose and a three-dimensional pose of the face, e) localizing facial features to extract an eye image of the face, f) estimating eye gaze of the person and estimating gaze direction of the person based on the estimated eye gaze and the three-dimensional facial pose of the person, g) detecting and tracking the person from second input images captured by the second means for capturing images, h) estimating a head position using the top-down view calibration, and i) estimating the gaze target of the person from the estimated gaze direction and the head position of the person using the face-view calibration.