This paper is concerned with an extended shape from shading and a photometric stereo using local shading analysis. In general the direction of the steepest change in the image plane corresponds to the steepest gradient of the reflectance map. The local shading expansion method is proposed using this characteristic. The shape from shading can be applied locally.by use of this method to extract surface orientation of objects with uniform Lambertian reflectance properties. The number of light sources of the photometric stereo can be reduced to two light sources by use of this local shading expansion method. Surface orientation of objects with non-uniform Lambertian or uniform specular reflectance properties can be obtained using this photometric stereo.
This paper presents the local shading expansion method and shows reconstructed shapes of objects using extracted surface orientation by this method.
