Improved physical-like virtual color filter for color separation of White-RGB CMOS sensor

White-RGB (WRGB) color filter array (CFA)-based CMOS sensor is a new and popular technique to improve the image quality directly with a higher sensitivity White (W) filter. Considering there is no color information in the pixel assigned to W, color separation from W raw data is necessary. We propose a color separation method based on a novel physicallike virtual color filters model for the WRGB CFA-based imaging system. The proposed algorithm can reproduce full color signal from W. In the filtering stage, the proposed algorithm provides three channel filter modes to imitate the physical color filter based on the wavelength responses. To reduce the deviation of the spectrum, a supervised learning technique is utilized to obtain the parameters. The Datacolor SpyderCheckr-based experimental results demonstrate that the proposed algorithm provides high accuracy color without the color artifact caused by the error of virtual filter, and the average improvement compared with the Gaussian ideal filter model is almost 90%.