Region-based illuminant estimation for effective color correction

Several algorithms were proposed in the literature to recover the illuminant chromaticity of the original scene. These algorithms work well only when prior assumptions are satisfied, and the best and the worst algorithms may be different for different scenes. In particular for certain images a do nothing strategy can be preferred. Starting from these considerations, we have developed a region-based color constancy algorithm able to automatically select (and/or blend) among different color corrections, including a conservative do nothing strategy. The strategy to be applied is selected without any a priori knowledge of the image content and only performing image low level analysis.