H.264运动估计算法在Imagine流处理器上的加速实现

H.264运动估计算法在Imagine流处理器上的加速实现:Imagine 是一款媒体处理的流体系结构芯片，它提供三级带宽层次，能够充分开发数据局域性和并行性，获得很高的性能。H.264 是目前最新的数字视频编码标准，它性能优越却计算复杂。并且，视频图像具有自然的流特性，空间局域性很好而时间相关性也有限。因此，我们认为H.264 编解码过程能够利用流处理来提高其性能。本文将H.264 编码中耗时较大的运动估计算法映射在Imagine 模拟平台上，实验结果表明，QCIF 图像编码效率可达438fps，远高于实时要求。与V1304 H.264 编码器的25fps 相比，加速比达到17.5 倍，
流处理的加速效果是非常明显的。由此证明，H.264 是适于Imagine 实现的。

Abstract: Imagine is a stream-based prototype chip designed for media processing. It uses a
three-level bandwidth hierarchy to exploit available parallelism and data locality. It has good
performance in media processing. H.264 is the newest digital video coding standard. It can
achieve high coding efficiency at the cost of complex computation. In addition, video pictures
have natural stream features, such as good special locality and limited temporal dependency. So it is thought that H.264 can increase its coding efficiency by stream processing. An accelerated implementation of motion estimation, which is the most time-consuming part in H.264 coding framework, on Imagine stream processor is presented in this paper. Experimental results show that the coding efficiency for QCIF format can be up to 438fps and meet real-time need. Compared with V1304 H.264 encoder, the speedup rate is 17.5x. The accelerated effect of stream processing is obvious. It proves that H.264 coding is suitable for implementation on Imagine.
关键词：Imagine 流处理器；H.264 视频编码；运动估计
Key words: Imagine stream processor; H.264 video coding; motion estimation