Patent attributes
There is provided a camera calibration device capable of highly precisely and easily estimating camera parameters without installing a piece of special calibration equipment or measuring 3D coordinates of reference points employed for calibration. A normal vector acquisition unit acquires normal vectors perpendicular to a reference horizontal plane from an image of a camera to be calibrated. A rotation matrix estimation unit projects the acquired normal vectors on a projection virtual plane perpendicular to the reference horizontal plane and evaluates that the projected normal vectors are perpendicular to the reference horizontal plane thereby to estimate a rotation matrix employed for calibrating the camera.