UHD Video Coding: A Light-Weight Learning-Based Fast Super-Block Approach
UHD Video Coding: A Light-Weight Learning-Based Fast Super-Block Approach
复制标题
超高清视频编码：一种基于轻量级学习的快速超级块方法
DOI：
10.1109/tcsvt.2018.2873910
复制
发表时间：
2019-10-01
影响因子：
8.4
通讯作者：
Ngan, King Ngi
中科院分区：
文献类型：
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作者：
Wang, Miaohui;Xie, Wuyuan;Ngan, King Ngi
超高清晰度（UHD）视频格式近来变得流行，其目的在于提供高空间分辨率、高时间帧速率、高采样比特深度和宽像素色域。尽管全球网络容量不断发展，但它不可避免地导致满足提供UHD视频服务需求的带宽成本增加。为了解决这些挑战，本文提出了一种用于高效视频编码（HEVC）中的UHD视频编码的改进的超级编码单元（SCU）方法。最初，提出了中等编码单元（MCU），以避免不必要的暴力编码单元（CU）分区的SCU。此外，SCU被提议通过Direct-MCU和SCU到MCU模式进行编码：Direct-MCU模式旨在更好地适应纹理丰富的区域，通过避免额外大小的CU分区来保证压缩效率; SCU到MCU模式被设计用于UHD内容的同质区域，通过跳过细粒度CU分区搜索来节省编码时间。此外，提出了一种基于学习的快速SCU决策方法，以加快直接MCU和SCU到MCU的确定过程，其中提取了三个代表性的手工特征。实验结果表明，与最近的HEVC参考软件相比，我们的方法在UHD视频编码中实现了可承受的复杂度和出色的编码效率（高达7.30%的Bjøntegaard Delta速率节省）。
The ultra high-definition (UHD) video format, which has recently become popular, aims to provide high spatial resolution, high temporal frame rate, high sample bit-depth, and wide pixel color gamut. Despite the continued development of global network capacities, it inevitably causes the increased bandwidth cost of catering to the requirement of delivering UHD video services. To address such challenges, this paper presents an improved super coding unit (SCU) method for UHD video coding in High Efficiency Video Coding (HEVC). Initially, the medium coding unit (MCU) is proposed to avoid unnecessary brute-force coding unit (CU) partitions of SCU. Furthermore, the SCU is proposed to be encoded by Direct-MCU and SCU-to-MCU modes: the Direct-MCU mode is intended to better adapt to the texture-rich region, which guarantees the compression efficiency by avoiding extra-size CU partition; the SCU-to-MCU mode is designed for the homogeneous region of UHD content, which saves the encoding time by skipping fine-grained CU partition search. Moreover, a learning-based fast SCU decision approach is proposed to speed up the determination process of Direct-MCU and SCU-to-MCU, where three representative handcrafted features are extracted. Experimental results show that our method achieves an affordable complexity and excellent coding efficiency (up to 7.30% Bjøntegaard Delta rate savings) in UHD video coding compared to recent HEVC reference software.