Chin Chye Koh, Jayanta Mukherjee and S.K. Mitra,
New efficient methods of image compression in digital cameras with color filter array(2003),
IEEE Trans. on Consumer Electronics, Vol. 49, no. 4, Nov., 1448-1456 
Abstract. 

Many consumer digital color cameras use a single light sensitive sensor and a color filter array (CFA) with each pixel element recording intensity information of one color component. The captured data is interpolated into a full color image, which is then compressed in many applications. Carrying out color interpolation before compression introduces redundancy in the data. In this paper we discuss methods and issues involved in the compression of CFA data before full color interpolations. The compression methods described operate on the same number of pixels as the sensor data. To obtain improved image quality, median filtering is applied as post-processing. Furthermore, to assure low complexity, the CFA data is compressed by JPEG. Simulations have demonstrated that substantial improvement in image quality is achievable using these new schemes.