Recently, a CFA sensor including a W channel has been developed. Since the W channel receives brightness information, it has a broad spectrum band compared to primary colors (Red, Green, Blue) and exhibits a high SNR. A camera using the CFA sensor obtains only certain type of color information for each pixel, so a color interpolation method is used to restore the full resolution image. In this paper, we propose a new color interpolation method for Sony-RGBW CFA. The proposed method is edge-adaptive and preferentially restores the W channel with a high sampling rate. In the next step, the R, G, and B channels are restored in the color difference domain using the W channel with the full resolution. Experimental results showed that the reconstructed image obtained by applying the proposed algorithm to the Sony-RGBW is superior to the image restored by conventional method in terms of SNR and visual confirmation.
Jonghyun Kim, Moon Gi Kang, "Color Interpolation Algorithm for the Sony-RGBW Color Filter Array" in Proc. IS&T Int’l. Symp. on Electronic Imaging: Image Processing: Algorithms and Systems XVI, 2018, pp 439-1 - 439-4, https://doi.org/10.2352/ISSN.2470-1173.2018.13.IPAS-439