Universal intra coding for arbitrary RGB color filter arrays in HEVC

• The first universal intra coding for mosaic videos with arbitrary RGB-CFAs in HEVC.
• The proposed scheme avoids the difficulty in converting irregular CFA structures.
• No color domain transformation is involved in the proposed scheme.
• Empirical results on ten typical RGB-CFAs demonstrate our algorithm is superior.

Compressing mosaic video sequences is necessary for storage and transmission over the internet. However, mosaic video sequences with different red–green–blue (RGB) color filter arrays (CFAs) require different compression schemes. We propose a two-stage universal intra coding scheme for compressing mosaic video sequences with arbitrary RGB-CFAs in high efficiency video coding (HEVC). Based on the associated mosaic structure, the proposed scheme first demosaics the neighboring reference pixels and then predicts the color value of the target pixel using the color values of the identical color components in the demosaiced reference pixels. Experimental results demonstrate that the proposed universal intra coding scheme achieves substantial improvement on bitrate while preserving the quality of the reconstructed video sequences.