New Shape-from-Shading Method with Near-Scene Point Lighting Source Condition

Imaging model is one of key factors of shape-from-shading (SFS) which reconstruct 3-D shape of objectives from only one image. Most existing SFS methods are based on orthogonal projection. But perspective projection is more accurate than orthogonal projection to simulate the imaging processes of cameras. In this paper, new SFS method under perspective projection with near-scene point lighting source condition is proposed. Imaging model under perspective projection with near-scene lighting source condition is formulated firstly. And the influence of the distance from lighting source to the surface is also considered in the reflectance map equation. Then a set of static Hamilton-Jacobi (H-J) equation is given by the reflectance map equation. The SFS problem is further formulated as viscosity solution of the H-J equation. And the Lax-Friedrichs fast sweeping numerical scheme based on the vanishing viscosity approximation theory is used to solve the H-J equation. At last, experiments on synthetic and real images are performed. Experimental results illustrated the efficiency of the proposed method.