this method is a SFS under-constrained problem and needs to solve other constraints. Therefore, the traditional method of SFS also based on three assumptions. The main advantage of the brightness of the method is that it can recover from a single image in a more precise three-dimensional model can be applied in addition to mirror the object almost all types of objects. However, the brightness of the reconstruction of relying solely on mathematical calculations, results are poor, but because of the lighting conditions more stringent requirements, the need to know the precise position and orientation of the light source and other information, so that the brightness of the method is difficult to apply in the case of an outdoor scene lighting and other complex three-dimensional reconstruction on. Photometric stereo.Although the shading method to support the reconstruction of three-dimensional model from a single image, but less information is available in a single image, the actual reconstruction of the general effect. So Woodham of SFS method is proposed to improve the photometric stereo. Photometric stereo by a plurality of non-collinear light source to obtain multiple images of the object, and then a different image brightness simultaneous equations, solving the surface normal direction of the object, and ultimately restore the shape of the object. Technically, the use of two light sources can be obtained method object to the information, but the use of multiple sources of data redundancy can be resolved by the shadows and specular reflections caused by such factors can not solve the problem, better robustness, reconstruction effect It can be improved, so the current method basically using a plurality of (four to six) three-dimensional reconstruction of the light source.