A modified soft-shape-context ICP registration system of 3-D point data

A facial point data registration system based on ICP is presented. The reference facial point data are extracted from patient's pre-stored CT images, and the floating facial point data are captured from the patient directly by using a touch or non-touch capture device. A modified soft-shape-context ICP, which includes an adaptive dual AK-D tree for searching the closest point and a modified objective function, is embedded in this system. The adaptive dual AK-D tree searches the closest-point pair and discards insignificant control coupling points by an adaptive distance threshold on the distance between the two returned closest points which are searched by using AK-D tree search algorithm in two different partition orders. In the objective function of ICP, we utilize the modified soft-shape-context information which is one kind of projection information to enhance the robustness of the objective function. Relying on registering the floating data to the reference data, the system provides the geometric relationship for a medical assistant system and a pre-operative training. Experiment results of using touch and non-touch capture devices to capture floating point data are performed to show the superiority of the proposed system.