White lenslet image guided demosaicing for plenoptic cameras

Most modern cameras use a color filter array on their sensor in order to capture color images. This array is composed of red, green and blue filters and so, each pixel on the sensor lacks two color channels which can be retrieved by a process called demosaicing. In this paper, we propose a new demosaicing method for plenoptic cameras. This type of cameras has become a growing trend and their captured raw images have a particular lenslet structure which must be taken into account to retrieve the sub-aperture images which compose the light field. First, we analyze and describe the flaws of the state-of-the-art light field decoding pipeline. To better identify the different sources of artifacts, our analysis is performed by generating ideal lenslet images from synthetic light fields and use them as input of the decoding pipeline. Then, we detail a new method of demosaicing based on the provided white lenslet images serving as guide. Furthermore, we show that this kind of guided interpolation can be useful on other steps of the decoding pipeline. Finally, the quality of the resulting sub-aperture images is assessed for both synthetic and real light fields using visual comparisons as well as objective metrics.