Highly Flexible Coding Structures for Next-Generation Video Compression Standard.

This paper describes the coding block structure used in the joint Qualcomm/Technicolor responses to the JVET call for proposal on video compression with capability beyond HEVC. The proposed block structure relies on the known quadtree plus binary tree (QTBT) block structure and brings some higher degree of flexibility in it. Two sets of partitioning modes extend QTBT: the ternary tree (TT) and the asymmetric binary tree (ABT). The added split modes are used with a normative non-redundancy policy, which ensures any block topology can be reached through a unique series of split modes. Finally, some flexible binary and ternary partitioning is allowed near the bottom and right picture borders. Overall, the proposed split modes, non-redundancy and picture border strategies lead to 19.6% bitrate reduction over HEVC.