Automated photogrammetric system for photorealistic skull 3D reconstruction

Wide variety of medical and archeological applications has a demand for skull geometric parameter measurements. Traditional contact measurement technique has some disadvantages such as low accuracy and a need for a real skull for processing. Applying of photogrammetric methods for non-contact spatial coordinates determination and 3D model generation allows to provide high precision and convenient interface for expert. However the problem of textured human skull 3D reconstruction seems to be rather complicated concerning the following aspects. The human skull is a real 3D object (differing from so called 2.5D objects), which can not be reconstructed basing on single stereo pair. The way of whole 3D model reconstruction basing on acquiring a set of stereo images covered the whole object surface is time consuming and requires a special (usually manual) mean for integration of obtained 2.5D fragments into united 3D model. Another requirement to skull 3D model is to provide for the expert the possibility of easy finding the object point, which has to be measured. Accurate photorealistic texture mapping can satisfy this requirement. The paper presents the approach, which provides high performance automated skull 3D reconstruction along with accurate texture generating, The system developed includes three CCD cameras, Pentium personal computer equipped with frame grabbers, structural light projector and PC-controlled turntable.