Improved universal chroma 4:2:2 subsampling for color filter array video coding in HEVC

Considering one color filter array (CFA) video whose CFA pattern can be any sort of ten well-known CFA patterns, prior to compression in High Efficient Video Coding, this paper presents an improved universal chroma 4:2:2 subsampling method for the CFA video. The proposed subsampling method has clear quality improvement merit because for any YUV block, we take the influence of the U component and V component when converting them to B/G pixels and R/G pixels, respectively, into account when determining the two subsampled U and V chroma values. To further improve the quality, a luma modification strategy is performed after chroma subsampling. Based on four typical test CFA videos, the experimental results demonstrate that the proposed subsampling method outperforms the four related state-of-the-art methods in terms of the objective and subjective quality metrics and the trade-off between the quality and bitrate.