Recovery of an SHGC shape and pose from shading and contour based on weak lambertian assumption

This paper discusses the quantitative method for recovering the pose and shape of the straight homogeneous generalized cylinder (SHGC), based on the quantitative constraint assuming the weak uniform random reflection (weak Lambertian assumption). The weak Lambertian assumption is a generalization of the strictly complete random reflection model (strict Lambertian model). No knowledge of the light source or the surface reflection coefficient is required in the proposed method. As a first step, the position of the axis of SHGC is determined on the image. Then, the weak Lambertian assumption is applied to the intensity distribution along the parallel (latitude) which corresponds to the extrema of the sweeping function on SHGC to recover its pose. Then, the weak Lambertian assumption is also applied to the intensity distributions along other parallels to recover the position of the axis of SHGC in the three-dimensional space. To demonstrate the effectiveness of the proposed method, an experiment is shown for the synthesized image and the real image.