Simultaneous CFA Demosaicking of Three Color Planes for Improved Color Accuracy

Color Filter Array (CFA) demosaicking is an interpolation process of reconstructing a full color image from a single image sensor. Conventionally, color planes are demosaicked sequentially. The green color plane is usually demosaicked first due to the fact that it contains twice the information of the othercolor planes for the Bayer pattern, and then followed by the demosaicking of red and blue color planes. However, this sequential process of demosaicking will produce color artifacts which cannot be recognizeduntil all the color planes have been demosaicked. In our paper, we propose a novel technique to demosaicthe three color planes simultaneously so as to avoid the selection of artifact pixels. Based on the interpolation in different directions to estimate a full color pixel for edge preservation, multiple combinations of RGB color values for a pixel location are generated. Among those RGB combinations, some are good estimates while others are color artifacts. Using the color–line property to discriminate those color artifact pixels, an optimum RGB color value from those good estimates will be selected. It has been shown that our proposed algorithm outperforms the other benchmarking algorithms and produces minimal color artifacts. The experimental results have shown consistency in performance in both perceptual and objective evaluation for various types of image datasets.