Rough Surfaces and Relief Extraction by Generalized Lambertian's Photometric Model

Within the framework of the analysis of 3D textured environment through image analysis, we approach here the case of the rough surfaces for the analysis of the local variations of their relief. Generally, the interaction between the light and these local relief variations leads to a textured image of these surfaces. The proposed approach is an original stereovision adaptation based on photometric model to the case of surfaces with a high degree of roughness and with Lambert's photometric behaviour. Indeed, the usual approach treats only the case of surfaces with weak roughness, without consideration of the phenomena such as interreflexions, shades or still maskings between elementary facets of surface. We propose to take into account these phenomena through the adaptation of Oren-Nayar's model for the photometric stereovision. A comparative study is done to put out the contribution of the proposed approach in the case of rough surfaces.