Classification of 3D rough surfaces using colour and gradient information recovered by colour photometric stereo

摘要

Directional effects of illumination make difficult classification of rough 3D surfaces as their appearance may change dramatically, especially when a surface has variable albedo. One way of circumventing the problem is to separate the local shape and albedo information prior to classification. We do it by means of Colour Photometric Stereo, which produces 5 descriptors for each surface patch: two gradient components, and three colour components. This information is illumination-invariant, and can be used as an input for a suitable classification scheme. We proceed to classify a collection of surfaces by matching their colour histograms and multidimensional co-occurrence matrices of shape descriptors.