Motion estimation (ME) is a high efficiency video coding (HEVC) process for determining motion vectors that describe the blocks transformation direction from one adjacent frame to a future frame in a video sequence. ME is a memory and computation consuming process which accounts for more than 50% of the total running time of HEVC. To conquer the memory and computation challenges, this paper presents ReME, a highly paralleled processing-in-memory (PIM) architecture for the ME process based on resistive random access memory (ReRAM).

In ReME, the space of ReRAM is mainly separated into storage engine and ME processing engine. The storage engine is used as conventional memory to store video frames and intermediate data, while the computation operations of ME are performed in ME processing engines. Each ME processing engine in ReME consists of Sum of Absolute Differences (SAD) modules, interpolation modules, and Sum of Absolute Transformed Difference (SATD) modules that transfer ME functions into ReRAM-based logic analog computation units. ReME further cooperates these basic computation units to perform ME processes in a highly parallel manner. Simulation results show that the proposed ReME accelerator significantly outperforms other implementations with time consuming and energy saving.

运动估计（ME）是一种用于确定运动矢量的高效视频编码（HEVC）过程，该运动矢量描述了视频序列中从一个相邻帧到未来帧的块转换方向。ME是一个消耗内存和计算的过程，占HEVC总运行时间的50％以上。为了克服存储和计算方面的挑战，本文提出了ReME，它是一种基于电阻性随机存取存储器（ReRAM）的用于ME过程的高度并行的内存处理（PIM）架构。

在ReME中，ReRAM的空间主要分为存储引擎和ME处理引擎。存储引擎用作常规存储器来存储视频帧和中间数据，而ME的计算操作是在ME处理引擎中执行的。ReME中的每个ME处理引擎均由将ME函数转换为基于ReRAM的逻辑模拟计算单元的绝对差总和（SAD）模块，插值模块和绝对变换差总和（SATD）模块组成。ReME进一步与这些基本计算单元合作，以高度并行的方式执行ME处理。仿真结果表明，所提出的ReME加速器在耗时和节能方面明显优于其他实现。