Shadow edge detection using geometric and photometric features

The detection of shadow and shading edges is a first step towards reducing the imaging effects that are caused by interactions of the light source with surfaces that are in the scene. As most of the algorithms for shadow edge detection use photometric information, geometric information have been ignored so far. In this paper, the aim is to include geometric features for more robust shadow edge detection. First, thousands of patches are annotated as either containing a shadow edge or not. Then, geometric features of these patches are analyzed and it is shown that the combination of photometric and geometric features improves the classification of shadow edges with respect to using either one of these features with 14%. These results demonstrate the added value of geometric features, in addition to photometric features, for the detection of shadow edges.