Recently, RGB-White(RGBW) sensors have been developed to take advantages of high-sensitive white(W) channel. Especially in the low light condition, the W channel has better SNR (Signal to Noise Ratio) characteristics than other color channels. In this paper, a new color interpolation method for the RGBW sensor is proposed. To make the best use of the high-sensitive W channel, we use a random pattern RGBW Color Filter Array(CFA). The most of pixels in the CFA sample the W channel values, when a small number of pixels sample the R, G, and B channel values respectively. At the initial step, missing W channel values in positions of pixels which sample the R, G, and B channel are estimated by edge adaptive scheme. After that, the color difference channels, i.e., R-W, G-W, and B-W, are estimated by the scheme of colorization. Experimental results show that the proposed algorithm performs better than the results from Bayer CFA in terms of SNR and object discrimination.
Paul Oh, Sukho Lee, Moon Gi Kang, "Color Interpolation Based on Colorization for RGB-White Color Filter Array" in Proc. IS&T Int’l. Symp. on Electronic Imaging: Image Processing: Algorithms and Systems XV, 2017, pp 67 - 71, https://doi.org/10.2352/ISSN.2470-1173.2017.13.IPAS-085