Generalized binary splits: A versatile partitioning scheme for block-based hybrid video coding

Block partitioning is the basis of every modern hybrid video coding standard. It specifies how the video pictures can be subdivided into blocks for prediction and residual coding. In H.265/HEVC, quad-tree partitioning is one of the key technologies allowing for flexible mode allocation and providing a substantial part of the gains over H.264/AVC. The current draft of the upcoming standard Versatile Video Coding (VVC) provides over 30% bit-rate savings over HEVC and almost one third of the gain is achieved by using a more flexible partitioning scheme than the quad-tree partitioning used in HEVC. In this paper, we describe a partitioning concept that generalizes many of the ideas developed during the exploration and early standardization phase of VVC. In fact, our method includes the VVC partitioning as well as many other state-of-the-art methods. The proposed method can be implemented in a fully configurable design. For instance, it can be configured to match the performance of VTM-1.0 at much faster runtime (69%) or it can be configured to obtain additional bit-rate savings of up to 3% by exploiting additional degrees of freedom.