视频数据存储方式及运动估计算法的内存访问效率

通过分析常用运动估计算法的内存访问模式,揭示出他们在通用计算机和数字信号处理器上使用时存在的效率问题,以及造成此问题的原因,并提出一种新的内存访问效率高的视频数据存储方式即叠瓦式存储方式。研究结果表明:使用新的视频数据存储方法,解决了跨缓存线访问数据的问题,并显著降低了运动估计过程中的高速缓存跑靶率;对全搜索算法,在算法本身不做任何改动的情况下,其运动估计过程速度提高28%。因此,叠瓦式存储方式的使用,可以有效地加速运动估计过程。

Video data layout optimization and memory access analysis for motion estimation

The memory access patterns of motion estimation algorithms were analyzed,the cache efficiency,related issues and the causes were revealed when they run on general PCs and digitial signal processors.A new cache efficient video data layout method,i.e.,overlapped tiled layout method,was presented.The results show that this new data layout method can be used to resolve the cache split loading issue and greatly reduce the cache miss rate.The new layout method can speed up the spiral full search motion estimation process for 28% without change of the motion estimation algorithm itself.So,the use of the overlapped tiled layout method can speeds up the motion estimation process.