摘要
在H.264、AVS2和HEVC等视频编码标准都通过算术编码将编码信息转换为码流。但是在编码过程中需要不断地通过算术编码获得准确的比特数从而计算率失真代价,严重影响了编码速度。为了降低视频编码过程中在算术编码模块巨大的时间消耗,针对AVS2中变换块编码进行优化,通过多种方法从三个角度分别对变换单元中形成的比特数进行估计,从而取代这一部分的算术编码过程,大大节省了在算术编码模块的开销,在很小的率失真代价损失的基础上,对算术编码模块的时间节省平均达到70%。
In video coding standards like H. 264, AVS2 and HEVC, arithmetic encoding plays an important role in the final stage of turning the coding message into streams. The arithmetic encoding in coding standards mostly focus on processing the syntax ele- ments in the coding units （CU）, in which the transform block （TB） costs the most of the bits. The rate-distortion optimization （RDO） process needs to have arithmetic encoding for every TB to get the accurate output bits and finally get the RDO cost we need. RDO processes cost a large amount of time and have a negative influence on coding efficiency. According to these facts, this paper focuses on the optimization of the arithmetic encoding in TBs in AVS2, tries to estimate the bit-cost of TBs from three aspects instead of a full process of arithmetic encoding so that to achieve the improvement of coding efficiency, the reduced time in arithme- tic encoding module reaches an average level of 70%.
出处
《电视技术》
北大核心
2017年第9期14-19,38,共7页
Video Engineering
基金
国家自然科学基金项目(61271212)
国家"863"计划项目(2015AA015903)
关键词
AVS2
算术编码
比特数估计
AVS2
arithmetic encoding
estimation of bit cost
