VVC，全名為Versatile Video Coding，是由Joint Video Experts Team (JVET) 制定的新一代視頻編碼標準，最終版本是在2020 年 7 月 6 日完成。在相同的編碼質量下，VVC的壓縮率會比上一代標準，即HEVC（High Efficiency Video Coding）高平均30-50%，但是其演算法更為複雜，因此編碼時間會比 HEVC 多數倍（甚至是10 倍）。因此，有必要對 VVC 演算法在最低影響BDBR的情況下進行優化，以減少其編譯時間。
本文將提出一種快速的幀間編碼決策方法，可以大量減少 VVC 的多元樹切割部分的編碼時間。我們分別針對二分樹和三分樹提出了優化的方法。在二分樹切割的部分，我們提出了使用平均殘差的差值來作為二分樹垂直或是水平切割的提早結束切割的決策條件。此外，我們使用二分樹決策結果與失真成本來判斷最佳方向，並提早結束與找到的最佳方向相反的三分樹預測。實驗結果表明，我們的方法減少了大約 44.1% 的編碼時間，而平均只增加了0.74的 BDBR。

The VVC, also known as Versatile Video Coding, is the new generation of video coding standards finalized on 6 July 2020 by the Joint Video Experts Team (JVET). Under the same encoding quality, the compression rate of the VVC will be 30-50% better than the previous generation standard, which is named HEVC (High Efficiency Video Coding). However, its coding time will be several times (up to 10 times) higher than HEVC. Therefore, it is necessary to optimize the VVC algorithm to reduce its compilation time with minimal influence of bitrate at the same time.
This paper will propose a fast inter coding prediction method that can reduce encoding time on the multi-tree partition of VVC. We have proposed two optimization methods for the binary tree and the ternary tree, respectively. Early termination on the binary tree splitting decision based on the two-block difference method is using to determine skipping unnecessary partitions. Moreover, a skip decision using the best direction obtained during the binary tree decision is another proposed method in the ternary tree. Experimental results showed that our approach had reduced about 44.1% encoding time with an average of 0.74 BDBR increases.

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