Novel color processing architecture for digital cameras with CMOS image sensors

This paper presents a color processing architecture for digital color cameras utilizing complementary metal oxide semiconductor (CMOS) image sensors. The proposed architecture gives due consideration to the peculiar aspects of CMOS image sensors and the human visual perception related to the particular application of digital color photography. A main difference between the proposed method arid the conventional systems is the fact that color correction module is located before the interpolation module. Therefore, a method of performing color correction on a color filter array (CFA) pattern is also provided in this paper. The interpolation algorithm is especially designed to solve the problem of pixel cross talk among the pixels of different color channels. The algorithm separates the green channel into two planes, one highly correlated with the red channel and the other with the blue channel. These separate planes are used for red and blue channel interpolation. The implementation details related to managing four color channel values is also described. Experiments conducted on McBeth color chart and natural images have shown that the proposed color processing chain produces better quality images with improved SNR.