Patent ID: 7263207

Claim:
A device for video tracking motions of an object, the device comprising: a calibration unit for obtaining intrinsic parameters of a video camera; a camera distortion compensation unit for receiving video data, acquired by the video camera, of a predetermined object on which at least one principal marker having a predetermined position is set and removing lens distortion from the received video data using the intrinsic parameters of the camera; a principal marker coordinate extraction unit for receiving the video data from which lens distortions are removed by the camera distortion compensation unit, and extracting two-dimensional coordinates of the video data of the principal marker set on the object, wherein the principal marker coordinate extraction unit comprises: a principal marker labeling unit for receiving the video data from which lens distortions are removed by the camera distortion compensation unit, assigning different labels to each color of marker and separating the markers into principal markers and additional markers, a noise canceling unit for receiving information about principal points corresponding to the principal markers, and additional points, corresponding to the additional markers from the principal marker labeling unit and canceling noise in two-dimensional regions of the principal markers, and a principal marker decision unit for receiving information about the two-dimensional regions of the principal markers and the additional points from which noise is canceled by the noise canceling unit and obtaining two-dimensional coordinates of the points in an image; and a position, orientation and direction of motion estimation unit for estimating and outputting a position, orientation and direction of motion of the object, based on the two-dimensional coordinates input from the principal marker coordinate extraction unit, the intrinsic parameters of the camera input from the calibration unit and three-dimensional coordinates of the at least one principal marker set on the object.