VVC/H.266会议提案阅读（三）之JVET-C1000

JVET-C1000

1、介绍

会议的一个主要目标是审查JEM2会议以来在过渡期间进行的工作。另一个重要的目标是回顾在评估视频压缩技术时为研究新测试视频材料的特性而进行的工作。此外，还审查了输入文件，并计划修改JEM3。

2、JEM2

JEM2.0的技术有：
1、Block structure
①Larger Coding Tree Unit (up to 256x256) and transforms (up to 64x64)
②Quadtree plus binary tree (QTBT) block structure only in EE SW branch
2、Intra prediction improvements
①65 intra prediction directions modified in JEM2.0 compared to JEM1.0
②4-tap interpolation filter for intra prediction
③Boundary filter applied to other directions in addition to horizontal and vertical ones
④Cross-component linear model (CCLM) prediction
⑤Position-dependent intra prediction combination (PDPC)
⑥Adaptive reference sample smoothing
3、Inter prediction improvements
①Sub-PU level motion vector prediction
②Locally adaptive motion vector resolution (AMVR)
③1/16 pel motion vector storage accuracy modified in JEM2.0 compared to JEM1.0
④Overlapped block motion compensation (OBMC)
⑤Local illumination compensation (LIC)
⑥Affine motion prediction modified in JEM2.0 compared to JEM1.0
⑦Pattern matched motion vector derivation
⑧Bi-directional optical flow (BIO)
4、Transform
①Explicit multiple core transform
②Mode dependent non-separable secondary transforms
③Signal dependent transform (SDT) disabled by default
5、Adaptive loop filter (ALF)
6、Enhanced CABAC design
①Context model selection for transform coefficient levels
②Multi-hypothesis probability estimation
③Initialization for context models

3、JEM与HEVC对比

在第二次JVET会议上，修改了常见的测试条件，更新了测试序列。因此，JEM1.0和JEM2.0之间的直接性能比较不是特别直观。下表显示了与HM相比，JEM1.0和JEM2.0的性能：

下表显示了JEM1.0和JEM2.0的性能比较：

剩下就是介绍此次会议每个提案的大致内容和总结，感兴趣的可以去看看。