实时HDTV720p H.264/AVC编码器分析与架构设计

需积分: 10 164 浏览量更新于2024-07-25 收藏 2.71MB PDF 举报

"这篇论文是关于高清电视（HDTV）720p 30帧每秒H.264/AVC编码器的分析与架构设计，主要探讨了H.264/AVC编码标准在视频编码性能提升的同时，所带来的巨大计算复杂度和内存访问需求问题，以及如何在硬件实现上应对这些挑战。" 正文: H.264/AVC编码标准是视频编码领域的一个重要里程碑，它在图像质量和压缩效率上显著优于前一代标准。然而，这种优越性能的背后，是极其复杂的计算任务和对内存的高要求，这使得实时应用中的硬件编码器设计变得困难。论文中，作者Tung-Chien Chen等人深入分析了H.264/AVC编码器在处理高清电视（HDTV）720p 30帧每秒视频时所面临的挑战。 H.264/AVC编码的核心算法包括熵编码、运动估计、变换和量化等，这些算法具有复杂性高、顺序性强和高度依赖数据的特点。这些特性限制了传统的方法，如流水线和并行处理技术的应用，从而降低了硬件利用率和编码速度。为了克服这些难题，作者提出了一种针对HDTV应用的H.264/AVC视频编码器设计方案。在系统设计层面，他们考虑了关键算法的特性，如块级、宏块级和帧级重建循环，以及如何优化这些流程以提高硬件效率和吞吐量。论文中可能涉及的具体技术包括： 1. **算法优化**：通过改进算法，减少不必要的计算和内存访问，以降低计算复杂度。 2. **硬件资源复用**：设计高效的硬件结构，使得同一硬件单元可以在不同阶段重复使用，提高硬件利用率。 3. **并行处理**：尽管H.264/AVC的顺序性和数据依赖性限制了并行化，但作者可能探索了在编码过程的不同阶段或不同任务间引入并行性的方法。 4. **流水线设计**：通过合理划分编码流程，实现各步骤之间的流水线操作，以提高处理速度。 5. **内存管理**：优化内存访问模式，减少存取延迟，以适应高带宽的需求。此外，论文还可能讨论了编码器的实时性、功耗、面积效率等关键性能指标，并可能提供了实验证明所提出设计的有效性和可行性。 "Analysis and Architecture Design of an HDTV720p 30 Frames H264/AVC Encoder"这篇论文详细探讨了在H.264/AVC标准下，如何设计一个能够处理高清视频的实时硬件编码器，以及解决其计算复杂度和内存需求问题的各种策略和技术。这项工作对于理解H.264/AVC编码器的实现细节，以及推动视频编码硬件技术的发展具有重要意义。

676 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY, VOL. 16, NO. 6, JUNE 2006

Fig. 2. Block diagram of the proposed H.264/AVC encoding system. Five major tasks, including IME, FME, IP, EC, and DB, are partitioned from the sequent

ial

encoding procedure and processed MB by MB in a pipelined structure.

A. Proposed Four-Stage Macroblock Pipelining

The proposed system architecture is shown in Fig. 2. Five

major tasks, including IME, FME, intra prediction with recon-

struction loop (IP), entropy coding (EC), and in-loop deblocking

ﬁlter (DB), are partitioned from the sequential encoding proce-

dure and processed MB by MB in pipelined structure.

Several issues of designing this system pipelining are de-

scribed as follows. The prediction, which is ME only in the

previous standards, includes IME, FME, and intra prediction

in H.264/AVC. Because of the diversity of the algorithms

and the difference in computational complexity, it is difﬁ-

cult to implement IME, FME, and intra prediction with the

same hardware. Putting IME, FME, and intra prediction in the

same MB pipelined stage leads to very low utilization. Even if

the resource sharing is achieved, the operating frequency be-

comes too high due to the sequentially processing. Therefore,

FME is ﬁrstly pipelined MB by MB after IME to double the

throughput. As for intra prediction, because of the MB-level

and the block-level reconstruction loops, it cannot be separated

from the reconstruction engine. In addition, the reconstruc-

tion process should be separated from ME and pipelined MB

by MB to achieve highest hardware utilization. Therefore, the

hardware engines of intra prediction together with forward/in-

verse transform/quantization should be located in the same

stage, IP stage. In this way, the MB-level and the block-level

reconstruction loops can be isolated in this pipeline stage. The

EC encodes MB headers and residues after transformation and

quantization. The DB generates the standard-compliant ref-

erence frames after reconstruction. Since the EC/DB can be

processed in parallel, they are placed at the fourth stage. The

reference frame will be stored in external memory for the ME

of the next current frame, which constructs the frame-level re-

construction loop. Please note that, the luma MC is placed in

the FME stage to reuse Luma Ref. Pels SRAMs and interpola-

tion circuits. The compensated MB is transmitted to IP stage

to generate the residues after intra/inter mode decision. The

chroma MC is implemented in IP stage since it can be exe-

cuted after intra/inter mode decision. In summary, ﬁve main

Fig. 3. MB schedule of four-stage MB pipelining.

functions extracted from the coding process are mapped into

the four-stage MB pipelined structure. The processing cycles

of the four stages are balanced with different degrees of par-

allelism to achieve high utilization. MBs within one frame are

coded in raster order with the schedule shown in Fig. 3. One

horizontal column indicates the MBs with different tasks that

are processed in parallel.

As for the reduction in system bandwidth, many on-chip

memories are used for three purposes. First, in order to ﬁnd

the best matched candidate, a huge amount of reference data

are required for both IME and FME. Since pixels in neigh-

boring candidate blocks are considerably overlapped, and so

are the search windows (SWs) of neighboring current MBs,

the bandwidth of the system bus can be greatly reduced by

designing local buffers to store reusable data. Second, rather

than transmitted through the system bus, the raw data such as

luma motion compensated MBs, transformed and quantized

residues, and reconstructed MBs are shifted forward via shared

memories. Third, because of data dependency, a MB is pro-

cessed according to the data of the upper and the left MBs.

The local memories are used to store the related data during

the encoding process. For the software implementation, the

external bandwidth requirement is up to 5570 GBytes/s. As for

the hardware solution with the local search window memories

剩余15页未读，继续阅读

wht_sleepyhead

粉丝: 0
资源: 1

实时HDTV720p H.264/AVC编码器分析与架构设计

H.264/AVC编码算法运动估计的判断

Stability Design of Steel Frame

Large capacity data hiding combined with secure-intra-watennarking based on H.264/AVC

java UDP通信 (传输协议包括RTP RTSP ONVIF) 输出H264/265的码流项目示例

srs_h264_write_raw_frames

制造alsa underrun 用C语言举例

android Camer2 H264

最新资源