Retinex Theory for Image Enhancement

Multi-scale retinex (MSR) processing has been shown to be an effective way to enhance image contrast, but it often has an undesirable desaturating effect on the image colors. A color-restoration method can help mitigate this effect, but our experience is that it simply leads to other problems. In this paper we modify MSR so that it preserves color fidelity while still enhancing contrast. We then add neural-net based color constancy processing to this modified version of MSR. The result is a principled approach that provides the contrast enhancement.