To improve efficiency of search engines, the query result cache has drawn much attention re- cently. According to the query processing and user＇s query logs locality, a new hybrid result cache strategy which associat...To improve efficiency of search engines, the query result cache has drawn much attention re- cently. According to the query processing and user＇s query logs locality, a new hybrid result cache strategy which associates with caching heat and worth is proposed to compute cache score in accord- ance with cost-aware strategies. Exactly, query repeated distance and query length factor are utilized to improve the static result policy, and the dynamic policy is adjusted by the caching worth. The hy- brid result cache is implemented in term of the document content and document ids （docIds） se- quence. Based on a score format and the new hybrid structure, an initial algorithm and a new rou- ting algorithm are designed for result cache. Experiments＇ results show that the improved caching policies decrease the average response time effectively, and increase the system throughput signifi- cantly. By choosing comfortable combination of page cache and docIds cache, the new hybrid cac- hing strategy almost reduces more than 20% of the only cache and docId-only cache. average query time compared with the basic page-展开更多
最新的视频编码技术H.264/AVC及可伸缩性扩展视频编码(Scalable Video Coding,SVC)通过多模式预测的方法实现了极高的压缩效率,同时也明显提升了编码复杂度。为减少SVC HighIntra Profile中增强层帧内编码模式选择的计算复杂度,本文提...最新的视频编码技术H.264/AVC及可伸缩性扩展视频编码(Scalable Video Coding,SVC)通过多模式预测的方法实现了极高的压缩效率,同时也明显提升了编码复杂度。为减少SVC HighIntra Profile中增强层帧内编码模式选择的计算复杂度,本文提出一种快速的帧内模式选择算法:通过对增强层少量帧的编码模式进行全搜索,确定增强层中各种编码模式的分布情况以及增强层与底层的纹理相关性,然后利用模式分布的统计结果,直接跳过出现概率很低的预测模式;同时,本算法利用层间相关性的统计结果,通过查表的形式,省去增强层部分低效预测方向的模式选择过程。实验结果表明,在几乎不影响率失真性能的前提下,本算法能节约50%以上的编码时间。展开更多
基金Supported by the National Natural Science Foundation of China(No.61173024)
文摘To improve efficiency of search engines, the query result cache has drawn much attention re- cently. According to the query processing and user＇s query logs locality, a new hybrid result cache strategy which associates with caching heat and worth is proposed to compute cache score in accord- ance with cost-aware strategies. Exactly, query repeated distance and query length factor are utilized to improve the static result policy, and the dynamic policy is adjusted by the caching worth. The hy- brid result cache is implemented in term of the document content and document ids （docIds） se- quence. Based on a score format and the new hybrid structure, an initial algorithm and a new rou- ting algorithm are designed for result cache. Experiments＇ results show that the improved caching policies decrease the average response time effectively, and increase the system throughput signifi- cantly. By choosing comfortable combination of page cache and docIds cache, the new hybrid cac- hing strategy almost reduces more than 20% of the only cache and docId-only cache. average query time compared with the basic page-
文摘最新的视频编码技术H.264/AVC及可伸缩性扩展视频编码(Scalable Video Coding,SVC)通过多模式预测的方法实现了极高的压缩效率,同时也明显提升了编码复杂度。为减少SVC HighIntra Profile中增强层帧内编码模式选择的计算复杂度,本文提出一种快速的帧内模式选择算法:通过对增强层少量帧的编码模式进行全搜索,确定增强层中各种编码模式的分布情况以及增强层与底层的纹理相关性,然后利用模式分布的统计结果,直接跳过出现概率很低的预测模式;同时,本算法利用层间相关性的统计结果,通过查表的形式,省去增强层部分低效预测方向的模式选择过程。实验结果表明,在几乎不影响率失真性能的前提下,本算法能节约50%以上的编码时间。
