主流视频编解码软件的硬件性能分析与设计

Hardware Performance Analysis and Design of Mainstream Video Codec Software

网络视频会议以及高清视频点播等应用的广泛流行,对视频编解码的编码质量以及编码速度提出了更高的要求。为帮助硬件设计人员设计更强大的专用处理器去适应视频编解码应用的发展趋势,并评估处理器设计的合理性和正确性,对视频编解码进行分析和测试,提出一套基准测试程序。采用自顶向下的分析方法,以流行性、编解码效率、压缩质量和开源性为标准,选取主流的视频编解码软件,进行热点函数分析。抽取变换、量化以及滤波过程中的热点函数,使之成为视频编解码测试程序,为其构造典型输入集。通过分析真实硬件平台上这些测试程序的计算和访存特性,给出处理器设计的建议。结果证明,该基准测试程序使用10%的代码量即可反映视频编解码过程的主要特征,对处理器设计具有指导意义。

As popular network video conference and high definition video on demand application is widely used, which puts forward higher requirements for video codec code quality and coding speed. In order to help hardware designers to build this kind of customized processors and evaluate their reasonability, this paper uses top-down analysis to solve these questions. It selects typical codec according to the popularity, coding efficiency, compression quality, and source accessibility. Hotspots of transformation, quantization and loop filter are extracted from coding process as kernels. These kernels are used to investigate the nature of the workloads. To better understand intrinsic characteristics of video coding application, it analyzes both computational and memory characteristics, and further provides insights into architectural design which can improve the performance of this kind of applications. Results show that this benchmark suite uses 10% codes to represent the main characteristics of video coding applications, and it is instructive and meaningful to processor design.