Multiresolution shape from shading

A method to reduce image resolution that simulates the reduction of shape resolution is presented. Such resolution reduction is critical for shape-from-shading algorithms. This method of resolution reduction is used in accelerating the shape from shading by using small multiresolution pyramids. A Lambertian reflectance model is used, but a similar approach can be developed for other reflectance models. The goal is to show that the resolution reduction based only on image intensities is inferior to resolution reduction using knowledge on the surface reflectance