一种适于镜面反射表面的从明暗恢复形状算法

摘要

In order to realize the fast shape reconstruction of specular reflection surfaces, an algorithm of shape-from-shading based on high-order fast marching method is proposed. First, assume that the light source is a point light source which is located at infinity. Second, the camera performs an orthographic projection whose direction is equal to the direction of the light source and the Blinn-Phong model is used to describe the reflectance property of the specular reflection surfaces. Then the image irradiance equation based on Blinn-Phong reflection model for specular surfaces is formulated and it is transformed into an Eiknoal partial differential equation including the shape of the surfaces. A high-order fast marching method is applied to compute a solution of the Eiknoal equation. Then, the 3D shape of the surfaces is obtained. Experimental results show that the proposed SFS algorithm can get the 3D shape reconstruction of specular reflection surfaces fast and accurately.%为了实现镜面反射表面快速重构的需求,提出了一种基于高阶Fast Marching方法的从明暗恢复形状算法.首先假定光源为点光源,且位于无穷远处,其次认为摄像机遵循正交投影,其方向与光源方向保持一致,接着使用Blinn-Phong模型来描述镜面反射表面的反射特性,建立基于Blinn-Phong反射模型的镜面表面图像辐照度方程,然后将该辐照度方程转化为含有高度信息的Eikonal偏微分方程,利用高阶Fast Marching方法计算上述Eikonal方程的解,从而获得镜面反射表面的三维形状.实验结果表明:提出的方法可以快速精确地实现镜面反射表面的三维重构.