From an RGB color image and under the assumption that the color of the illuminating light is known, a method for recovering the diffuse reflection component of the observed scene is proposed. In contrast to previously proposed approaches, no direct spatial connection of pixels properties is assumed. Drawing upon the dichromatic reflection model, the specular-free image is produced by projecting each observed color onto a plane that is tangent to an estimate of the material's body reflection color. Body color estimates are obtained by looking at how observed colors distribute in RGB space. The proposed approach is tested on synthetic and real images.
Javier Toro, "Obtaining the Diffuse Reflection from a Single Color Image" in Proc. IS&T 14th Color and Imaging Conf., 2006, pp 74 - 77, https://doi.org/10.2352/CIC.2006.14.1.art00014