Geometry, Imaging and Computing
Volume 2 (2015)
Automated modeling of reflectance properties for industrial plant primitives
Pages: 3 – 22
This paper outlines a method for determining reflectance parameters for modeling and rendering industrial plant primitives. The reflectance parameters are diffuse and specular material properties and the industrial plant primitives are pipes from raw LiDAR brightness data. For diffuse reflectance, the Lambertian model is compared to the Oren-Nayar model, and methods for estimating both are presented. For specular reflectance, the Phong model, commonly used in computer graphics, is used. The brightness data acquired from LiDAR systems are modeled as two different ideal cylinders to recover the diffuse and specular reflectance parameters and to illustrate the proposed method. A measured cylinder using brightness data acquired from a LiDAR scanner is also analyzed, and the diffuse and specular reflectance parameters are estimated. The estimate for the specular coefficient and exponent of the ideal cylinder are within 3.5% and 3.6%, respectively and the estimate for the Lambertian reflectance albedo for the ideal cylinder is within 0.02% of the actual value. The estimate for the diffuse reflectance and roughness parameters for the second ideal cylinder are within 0.3% and 1.2%, respectively. The estimated reflectance model of the measured cylinder have a mean relative error of 2.88% and a standard deviation of relative error of 4.0%.
Published 21 September 2015