基于内容的自适应插值滤波器在无损视频编码中的应用

Content Adaptive Interpolation Filters for Lossless Video Coding

为了解决高效率视频编码(high efficiency video coding,HEVC)帧间运动补偿中亚像素插值使用的固定插值滤波器无法自适应于视频序列内容所造成的预测精度下降的问题,针对HEVC无损压缩提出一种自适应插值滤波器方案.该方案通过极小化帧间预测误差得到自适应插值滤波器,对所有的帧间编码块通过自适应插值滤波器来获取亚像素预测像素块,自适应减少帧间预测误差,从而提升整体编码性能.将该方案应用于HEVC参考软件HM (HEVC test model) 12. 1中,实验结果表明,在不影响编解码端时间复杂度的情况下,所提出算法的压缩效率在low delay P和low delay B配置文件下分别比HEVC无损压缩效率平均提升1. 32%和0. 69%.

Focused on the issue that the fixed interpolation filters cannot adapt to the video content in high efficiency video coding(HEVC)motion compensation,which may compromise inter-prediction accuracy,an adaptive interpolation filter scheme was proposed for HEVC lossless coding.Adaptive interpolation filters were derived for each frame by minimizing the inter prediction difference,which reduced the inter prediction difference adaptively by generating the sub-pixels with the derived filters for all inter coding blocks resulting in better coding efficiency.The proposed scheme was implemented into the HM(HEVC test model)12.1 software.Experimental results show that the proposed scheme can achieve 1.32%and0.69%bit rate saving on average compared with HEVC under the'low delay P'and the'low delay B'configurations,respectively,which barely sacrifices the encoding and decoding time.