Extended Coding Unit Partitioning for Future Video Coding

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

14 Scopus Citations
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  • Junru Li
  • Li Zhang
  • Kai Zhang
  • Hongbin Liu
  • Siwei Ma

Related Research Unit(s)


Original languageEnglish
Article number8917942
Pages (from-to)2931-2946
Number of pages16
Journal / PublicationIEEE Transactions on Image Processing
Online published28 Nov 2019
Publication statusPublished - 2020


The flexible partitioning structure such as quad-tree plus binary-tree (QTBT) plays important roles in the next generation video coding standard. This paper investigates new coding unit (CU) partitioning methods to further improve the compression efficiency. In particular, we propose the extended quad-tree partitioning and asymmetric ternary-tree partitioning to further develop the principle behind the existing partitioning structure. First, a central extended quad-tree (CENTRAL-EQT) partitioning is introduced, which extends the traditional QT partitioning with central pattern and generates four elaborately designed sub-CUs with different sizes. Second, we propose a parallel extended quad-tree (PARALLEL-EQT) partitioning that allows the CU to split along a single direction, leading to four identical size sub-blocks. Third, we present an asymmetric ternary-tree (ATT) method, which splits the CU asymmetrically into three sub-blocks. The proposed new partitioning methods allow the interleaving with binary-tree partitioning for enhanced adaptability, and they can be jointly enabled to capture different characteristics of the local content. Simulation results on the JEM7-QTBT-Only platform show that averagely 4.92%, 4.81% and 5.08% BD-Rate savings are achieved for the luma component by the proposed methods under random access (RA), low-delay P (LDP) and low-delay B (LDB) configurations, respectively, with around 725% encoding time increase and negligible decoding time increase. Furthermore, experimental results also reveal that the proposed partitioning schemes are effective when cooperating with the upcoming Versatile Video Coding standard.

Research Area(s)

  • asymmetric ternary-tree partitioning, CU partitioning, quad-tree partitioning, video coding

Citation Format(s)

Extended Coding Unit Partitioning for Future Video Coding. / Wang, Meng; Li, Junru; Zhang, Li et al.

In: IEEE Transactions on Image Processing, Vol. 29, 8917942, 2020, p. 2931-2946.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review