Inter prediction is one of the key technologies enabling the high compression efficiency of modern video coding standards. 360-degree video needs to be mapped to the 2D image plane prior to coding in order to allow compression using existing video coding standards. The distortions that inevitably occur when mapping spherical data onto the 2D image plane, however, impair the performance of classical inter prediction techniques. In this paper, we propose a motion-plane-adaptive inter prediction technique (MPA) for 360-degree video that takes the spherical characteristics of 360-degree video into account. Based on the known projection format of the video, MPA allows to perform inter prediction on different motion planes in 3D space instead of having to work on the - in theory arbitrarily mapped - 2D image representation directly. We furthermore derive a motion-plane-adaptive motion vector prediction technique (MPA-MVP) that allows to translate motion information between different motion planes and motion models. Our proposed integration of MPA together with MPA-MVP into the state-of-the-art H.266/VVC video coding standard shows significant Bjontegaard Delta rate savings of 1.72% with a peak of 3.97% based on PSNR and 1.56% with a peak of 3.40% based on WS-PSNR compared to the VTM-14.2 baseline on average.
翻译:内部预测是使现代视频编码标准达到高压缩效率的关键技术之一。 360度视频需要在编码之前被映射到 2D 图像平面上,以便使用现有视频编码标准进行压缩。 但是,在2D 图像平面上绘制球状数据时,必然会出现扭曲现象,但这种扭曲现象会损害古典间预测技术的性能。 在本文件中,我们提议对360度视频采用运动-飞机-适应性预测技术,考虑到360度视频的球状特性。根据视频的已知投影格式,MPA允许对3D空间的不同运动平面进行相互预测,而不是直接在理论上任意绘制2D图像图解压缩。我们进一步提出运动-平面运动-运动矢量预测技术(MPA-MVPP),以便能够翻译不同运动机和运动模型之间的运动信息。我们拟议将MPA和MPA-MVPP纳入最新版H. 266/VC视频C视频编码标准中。根据H. 266/VC 视频编码标准,可以对3DM. 3-MS 最高节节节节节节节节节节节节节节节节节节节中重大Bjantega 56%的节节节节节节节节节节节节节节节率比0.3.56%至3.52%,以PM节节节节节节节节节节节节节节节节节节节为0.3.52%的峰为3.52%,以PM节节节节为0.3至0.3%的峰为0.3。