Optical-flow-based movement tracking of the temporomandibular joint in digitized sequential images of X-ray television

Movement estimation of the temporomandibular joint from sequential images of X-ray television comprises two procedures: (1) computation of the velocity field (optical flow) from two successive images; and (2) estimation of the velocity and the angular velocity (motion parameters) from data of the optical flow. The mandibular head of the X-ray image is observed merely as its blurred profile, superimposed by images of cranial bones. In order to achieve the movement tracking in such image data of inferior quality, the authors developed an accurate estimation of the optical flow using the Gabor wavelet transform, and an iterative estimation of the motion parameters. Through experiments employing an actual image-sequence of the TMJ, the authors' methodology was verified to be effective for improving the estimation accuracy of the movement, thereby the successful tracking of the mandibular head being achieved.