Being able to recognize the lighting conditions of a colour image is often critical in several imaging domains such as Pattern Recognition, Image Indexation, Image Enhancement and Augmented Reality. My work in this field in collaboration with Serge Beucher at the Centre of Mathematical Morphology has been particularly
orientated towards the shadow detection/analysis problem and the dichromatic colour constancy. From this work were produced:

A PhD thesis entitled : Mathematical Morphology Applied to the Analysis of Lighting Conditions of Colour Images.  The document written in French can be download here. In English, an abstract can be found here.

3 patents :

1. Valéry Risson  Kodak patent N° 0108907 « Method for detection shadows in a colour image ».
2. Valéry Risson  Kodak patent N° 0108912 « Method for detecting sky in a colour image ».
3. Valéry Risson  Kodak patent N° 0115098 « Method for detecting the illuminant in a colour image ».