Demosaicking algorithm for white-RGB CFA images

초록

WRGB colour filter array (CFA) has attracted much attention because it is structurally advantageous to improve image quality in low-light environment using high sensitivity of W channel. However, the demosaicking techniques for WRGB CFA image sensors developed so far have suffered from blurring at edges and deterioration in image quality due to the lack of correlation between W and RGB channels. In order to overcome the above problems, this paper proposes a correlation error compensation in W channel and a G channel restoration to mitigate blurring via edge adaptive filtering. In addition, the authors propose a brightness enhancement method utilising W channel, while avoiding noise boosting. Experimental results show that the proposed demosaicking algorithm not only shows better subjective visual quality than the existing technique but also has about 15% higher signal-to-noise ratio (SNR) than conventional Bayer CFA image.

키워드