Three Dimensional Reconstruction of Forward-Looking Sonar Images Based on Oren and Nayar Model

Shape from shading(SFS) algorithm, based on Lambert diffuse reflection model, is often utilized for three-dimensional(3D) reconstruction from two-dimensional(2D) forward-looking sonar image. However, the Lambert model has been demonstrated to be an inaccurate approximation to the diffuse component, so traditional SFS is not reliable to reconstruct the 3D model. This paper applies a modified SFS algorithm in optics, based more accuracy Oren and Nayar diffuse reflection model, to the 3D reconstruction from 2D sonar images. After verification of the simulation data and sea trial data, the 3D model, reconstructed by the algorithm in this paper, is closer to the actual size of objects and recovers the details of objects better. Thus the modified SFS algorithm, in this paper, is more accurate than the traditional SFS in 3D reconstruction from 2D forward-looking sonar images.