A performance characterization of high definition digital video decoding using H.264/AVC

Abstract

Abstract-H.264/AVC is a new international video coding standard that provides higher coding efficiency with respect to previous standards at the expense of a higher computational complexity. The complexity is even higher when H.264/AVC is used in applications with high bandwidth and high quality like high definition (HD) video decoding. In this paper, we analyze the computational requirements of H.264 decoder with a special emphasis in HD video and we compare it with previous standards and lower resolutions. The analysis was done with a SIMD optimized decoder using hardware performance monitoring. The main objective is to identify the application bottlenecks and to suggest the necessary support in the architecture for processing HD video efficiently. We have found that H.264/AVC decoding of HD video perform many more operations per frame that MPEG-4 and MPEG-2, has new kernels with more demanding memory access patterns and has a lot data dependent branches that are difficult to predict. In order to improve the H.264/AVC decoding process at HD it is necessary to explore a better support in media instructions, specialized prefetching techniques and possibly, the use of some kind of multiprocessor architecture.

Complexity/Performance Analysis of a H.264/AVC Video Encoder

“…The H.264/AVC has been designed with the goal of enabling significantly improved compression performance relative to all existing video coding standards (Joch et al, 2002). Such a standard uses advanced compression techniques that in turn, require high computational power (Alvarez et al, 2005). For a H.264 encoder using all the new coding features, more than 50% average bit saving with 1-2 dB PSNR (Peak Signal-to-Noise Ratio) video quality gain are achieved compared to previous video encoding standards (Saponara et al, 2004).…”

A Highly Scalable Parallel Implementation of H.264

“…The computing power demand increases also with the shift towards high definition resolutions. As a result, current high performance uniprocessor architectures are not capable of providing the performance required for real-time processing [10,11]. Therefore, it is necessary to exploit parallelism.…”

Scalability of Macroblock-level Parallelism for H.264 Decoding

“…As a result of the of the increased computational requirements current high performance uniprocessor architectures are not capable of providing the performance required for realtime HD processing [4] and, therefore, it is necessary to exploit thread level parallelism. Among different approaches MB-level parallelization has been proposed as a scalable technique for the H.264 decoder [6], [10], [8], [11], [12].…”

“…To provide higher compression efficiency without sacrificing quality advanced video codecs like H.264 and VC-1 have been proposed [3]. The combination of the complexity of these video codecs and the higher quality of HD systems has resulted in an important increase in the computational requirements of the emerging video applications [4].…”