A new shape from shading algorithm for hybrid surfaces

作者：Wang Guo Hui^*; Han Jiu Qiang; Zhang Xin Man; Ni Jin Ping

来源：Journal of Astronautics, 2011, 32(5): 1124-1129.

DOI：10.3873/j.issn.1000-1328.2011.05.023

• Hamilton-Jacobi
• Hybrid surface
• Image irradiance
• Mean absolute error
• Optical center
• Orthographic projections
• Perspective projections
• Reflectance model
• Root mean square errors
• Shape from shading
• Shape from shading algorithms
• Shape information
• Three-dimensional surface
• Viscosity solution
• Viscosity solutions

In the light of the high error of traditional shape from shading (SFS) algorithms of hybrid surfaces, a new SFS algorithm for hybrid surfaces based on perspective projection is proposed. First, an improved Ward reflectance model is applied to describe the hybrid surfaces and the perspective projection is used to model the camera. Assuming that the light source is located at the optical center of the camera, the image irradiance equation is established for this model. Then the equation is transformed into the Hamilton-Jacobi partial differential equation (PDE) including the shape information of the surface. The viscosity solution of the resulting PDE is approximated by using the fixed-point iterative sweeping method and the 2D central Hamiltonian, and heights of three-dimensional surface are obtained. The proposed algorithm is more effective and accurate than the existing same kind of methods. Experimental results on synthetic vase image show that the mean absolute error and root mean square error of the height of the proposed algorithm are dropped greatly, compared with the algorithm based on orthographic projection.

• 出版日期2011