This paper proposes a method for tracking the camera motion of the real endoscope by using the virtual endoscopy system. One of the most important advantages of the virtual endoscopy is that the virtual endoscopy can visualize information of other organs that are existing under the wall of the target organ. If it is possible to track the viewpoint and the view direction of real endoscopy (fiberscope) in the examination of the patient and to display various information obtained by the virtual endoscopy onto the real endoscopic image, we construct a very useful system for assisting examination. When a sequence of real endoscopic images is inputted, tracking is performed by searching a sequence of viewpoints and view directions of virtual endoscope that correspond to camera motions of the real endoscope. First we roughly specify initial viewpoints and view directions that correspond to the first frame of the real endoscopic image. The method searches the best viewpoint and view direction by calculating matching ratio between a generated virtual endoscopic image and a real endoscopic image within the defined search area. Camera motion is also estimated by analyzing video images directly. We have applied the proposed method to video images of real bronchoscopy and X-ray CT images. The result showed that the method could track the camera motion of real endoscope.
展开▼
