Adaptive CU partition and early skip mode detection for H.266/VVC


The Joint Video Exploration Team (JVET) has started to develop the next-generation video coding standard-H.266/Versatile Video Coding (H.266/VVC) based on H.265/High Efficiency Video Coding (H.265/HEVC) to provide higher compression performance. The H.266/VVC supports the flexible quadtree with a nested multi-type tree (QTMT) partition structure including quadtree (QT), binary tree (BT), and ternary tree (TT). The coding unit (CU) sizes range from 128 to 4 for the luma component or from 64 to 2 for the chroma component in the QTMT splitting structure. The introduction of small CU size, i.e., 2×N, leads to inefficient hardware implementation because it causes pipeline delayed and needs to process 2×N pixels in the hardware architecture. In addition, the inter or bi-predicted of small CU requires a higher memory bandwidth than the bi-predicted of 8×8 CU in H.266/VVC. To solve the above issues, we introduce a fast method to accelerate CU partition and mode decision, including an adaptive CU partition method and early skip mode detection method. The proposed algorithm consists of two parts: (1) adaptive remove 2×N CUs by skipping BT and TT splitting mode; (2) early skip bi-predicted or inter prediction of small CU. The experimental results demonstrate that the proposed scheme can save 47% coding time while maintaining the coding performance.

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This work was supported in part by the National Natural Science Foundation of China No. 61771432, 61302118, 61773018, 61702464, and 61803346, the Basic Research Projects of Education Department of Henan No. 21zx003, and 20A880004, and the Key Research and Development Program of Henan No. 202102210179.

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Zhang, Q., Wang, Y., Jiang, B. et al. Adaptive CU partition and early skip mode detection for H.266/VVC. Multimed Tools Appl (2021).

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  • H.266/VVC
  • Adaptive CU decision
  • Early skip
  • Intra prediction