Perceptual comparison of demosaicing algorithms and in-camera demosaicing with JPEG compression

Color image acquisition in digital cameras is often performed by using CCD or CMOS sensor chips with a color filter array on the top of a single monochromatic sensor. In this paper, a perceptual comparison is per- formed among three well known demosaicing algorithms plus in-camera demosaicing with lossy compression JPEG, by means of subjective tests, that is with the help of human beings. The novelty of the approach is that chosen algorithms have been selected as representative of those used in commercial raw image converters used by professionals in graphics and that the test has been performed on a large number of people, achieving results only partially similar to the results got by means of computed metrics. The results show that in the greatest part of conditions and for non particularly expert users, the capability of the most advanced demosaic- ing algorithms of producing an almost perfect reconstruction on the full-color image is not strictly required. Only for selected categories of images it is possible to find a clear winner among the algorithms.