Estimation of the Illuminant Colour Using Highlights from Human Skin
نویسندگان
چکیده
The knowledge of the illuminant colour exposing an object or a scenario is very useful for computer vision and allows much more reliable colour based recognition and interpretation. In many computer vision applications humans are important parts of the scenario and the obvious detection of human skin colour is difficult due to varying illumination. Under certain conditions of direct illumination the skin shows highlights. It is well known that highlights of non-homogeneous dielectric materials, such as skin, contain information about the illuminant colour. This paper investigates how accurately the illuminant colour may be estimated from highlights on skin using the Dichromatic Reflection Model. The proposed method extracts automatically the surface vector from a pixel area around a highlight on the tip of a human nose. Experimental results with frontal view images of human faces having different shades of skin taken under different illumination colours and geometries show the estimation of the illuminant colour vector orientation within a few degrees.
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