Local-constrained quadtree plus binary tree block partition structure for enhanced video coding
In the latest Joint Video Exploration Team (JVET) development, a quadtree plus binary tree (QTBT) block partition structure is proposed for enhanced video coding. Compared to the quadtree block partition in HEVC, QTBT can achieve much better compression performance at the expense of largely increased encoding computational complexity. In this paper, a fast QTBT block partition algorithm based on the local constraint is proposed. Given the decoded information of the previous frame, the partition parameters can be dynamically derived for each coding tree unit (CTU) without any overhead. Furthermore, a constrained binary tree partition algorithm is proposed to reduce the redundancy between the quadtree partition and the binary tree partition. Experimental results have shown that the proposed scheme can speed up QTBT block partition structure by 30% on average without obvious performance decrease, which enables its practical implementations in real application scenarios.