Extended Cross-Component Prediction in HEVC

The support for chroma formats other than 4∶2∶0 and bit depths higher than 10 bit has been included into the High Efficiency Video Coding (HEVC) standard by the publication of Version 2. In contrast to 4∶2∶2 profiles without additional dedicated coding tools relative to the Main profile, all 4∶4∶4 profiles specify a novel compression efficiency tool referred to as Cross-Component Prediction (CCP). This paper describes and analyses two additional extensions relative to the specified CCP variant in Version 2. In the first extension, an additional predictor is introduced, particularly, the first chroma component can also serve as the predictor for the second chroma component beside the luma component. The second extension is concerned with the binarization of the single prediction model parameter, which usually has a different distribution for R′G′B′ than for Y′CbCr content. Experimental results show that the in this paper presented extensions can improve the compression efficiency by −0.7% on average for R′G′B′ content, and by −1.1% for Y′CbCr content, respectively, both in terms of BD rate.