Chroma subsampling for HDR video with improved subjective quality

Many proposed high dynamic range (HDR) video coding schemes employ a float to integer transform with a subsequent standard low dynamic range (LDR) video codec. Standard LDR video codecs often work with subsampled chrominance components, usually 4:2:0. In this work we subjectively evaluate float to integer transforms and chroma subsampling for HDR video coding. An adaptive logLuv transform with 12 bit luma component and 8 bit chroma components proves adequate for HDR video coding. A novel chroma subsampling technique is proposed to avoid color bleeding artifacts while preserving the saturation. Subjective tests show improved performance over other known subsampling techniques.