3D Shape Reconstruction Using Three Light Sources in Image Scanner

We suggest the method t o recover the 3D shape of the object by using the color image scanner which has three light sources. The photometric stereo is traditional t o recover the surface normal of the object using the multiple light sources. In this method, it usually assumes the distant light sources to make the model simple. But the light sources in the image scanner are so close t o the object that the illuminant intensity varies with the distance from the light source, therefore these light sources should be modeled as the linear light sources. In this method, by using this models and two step algorithm; the initial estimation by the iterating computation and the optimization by the non-linear least square method, not only the surface normal but also the absolute distance from the light source t o the surface are estimated. By this method, we can recover the 3D shape more precisely. In the experimental results, the reconstruction of the 3D sh&e of the real object is shown. The proposed method changes the image scanner into the shape scanner. It makes the 3D d a t a acquisition easily, so it will be very useful in the CAD/CAM and the virtual reality system.