Fast block partitioning scheme for chrominance intra prediction of versatile video coding standard

We present a fast block partitioning scheme for chrominance intra prediction of the Versatile Video Coding (VVC) standard. VVC adopted several innovative tools to improve the coding performance compared with its predecessor standard, enabling the efficient handling of emerging video content such as ultra-high definition (UHD). These coding performance improvements come at the cost of a significant increase in coding complexity, mainly due to the new block partitioning structure called quadtree with nested multi-type tree (QTMT), which can be applied separately for luminance and chrominance components. Thus, this work proposes a scheme focusing on chrominance intra coding, composed of chrominance splitting early termination based on luminance QTMT and fast chrominance split decision based on the sub-block variances. Experimental results demonstrated that the proposed scheme provides 60.03% and 8.18% of chrominance and total encoding time savings, respectively, with a negligible impact of 0.66% in the YUV-BDBR. (C) 2021 SPIE and IS&T