Shape from shading using genetic algorithm

In this paper, a method for reconstructing a 3D shape of an object from a 2-D shading image using a genetic algorithm (GA), which is an optimizing technique based on mechanisms of natural selection, is proposed. In the proposed method, reconstruction of shapes from shading images can be regarded as a kind of optimization problem, that is to search for the shape providing the most similar shading image to the shading image of the original object, and then, the GA is applied to solving the optimization problem. Each candidate of the shape corresponds to an individual in the population. The fitness value of each individual is decided from the similarity of the shading image provided by the candidate of the shape to the measured shading image. The individuals with higher fitness values are selected according to mechanisms of natural selection of the GA, and then the 3D shape providing the highest fitness value, which is the reconstructed shape of the object, can be found finally. Using the proposed method, 3-D shapes reconstructed from shading images of synthesized objects which are calculated by computer simulation and those of real objects which are obtained with a CCD camera. The results of the reconstruction demonstrate the effectiveness of the proposed method