Skull outer contour extraction image using compass scanning

Skull outer contour extraction is an important step for craniofacial reconstruction. It useful for performing surface reconstruction. Skull outer contour obtained by three stages: thresholding, defining region of interest, and skull outer contour extraction. Compass scanning is used to this extraction. Scanning is performed using eight compass directions, four scanning are done from the four edges of ROI area, and the other four from corner of ROI area. This proposed method successfully extracts skull outer contour for four sample slices: upper temple, eye, nose, and mouth. Scanning from four corners of ROI area gives better result than four edges of ROI area, but using all eight scannings will give the best extraction performance.