一种新的视频编码的块运动估计算法

本文提出了一种连续判别的非线性预测搜索ＮＰＳＳＤ块运动估计算法,可以用于视频压缩的一些国际标准,如Ｈ．２６１,Ｈ．２６３,ＭＰＥＧ１,ＭＰＥＧ２,ＨＤＴＶ中。ＮＰＳＳＤ算法充分利用了序列图像的实际运动矢量与预测矢量之间的位移的空间分布特性－－中心偏置分布特性和时间上的相关特性,并在搜索过程中采用了中止判别和搜索判别,可以明显地减少运动搜索复杂度。仿真表明这种算法减少了搜索次数,提高了搜索效率,降低     

A Content-Based Search Algorithm for Motion Estimation

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符合人眼视觉特征的H.263编码方案

在研究视觉阈值效应和视觉掩盖效应的基础上,提出了一个符合人眼视觉特征的失真判断准则,并将其应用到Ｈ．２６３视频编码中,以达到提高编码速度的目的。实验结果表明,这种基于人眼视觉特性的失真判断方法能在保证恢复图像主观质量和压缩效率的前提下,有效地提高编码速率。     

High‐Performance Spatial and Temporal Error‐Concealment Algorithms for Block‐Based Video Coding Techniques

A compressed video bitstream is sensitive to errors that may severely degrade the reconstructed images even when the bit error rate is small. One approach to combat the impact of such errors is the use of error concealment at the decoder without increasing the bit rate or changing the encoder. For spatial‐error concealment, we propose a method featuring edge continuity and texture preservation as well as low computation to reconstruct more visually acceptable images. Aiming at temporal error concealment, we propose a two‐step algorithm based on block matching principles in which the assumption of smooth and uniform motion for some adjacent blocks is adopted. As simulation results show, the proposed spatial and temporal methods provide better reconstruction quality for damaged images than other methods.     

基于DSP的H.263码流复合

叙述一种采用DSP实现H.263标准规定的码流复合部分的方法。为了达到实时性的要求，对VLC码表的查表方法和DSP汇编程序进行了优化。所提出的码流复合优化方法已在H.263标准的硬件系统中实现。并且准备应用于MPEG－4标准的硬件系统中。     

An Error Concealment Approach Based on H.263 Video Decoding in Pixel Domain

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基于VC++的H.263到MPEG-4视频流转码的实现

在对H.263和MPEG-4两种视频编码标准以及几种常见转码器结构进行对比的基础上,基于VC++,在PC平台上实现了H.263到MPEG-4的转码系统.通过Foreman标准测试序列的码流进行转码测试,结果没有察觉图像失真,说明该方法能够达到较满意的效果.     

Scalable Parallel Memory Architectures for Video Coding

Current video compression standards, which process frames macroblock by macroblock, employ several processing functions to achieve the compression. These functions refer to data memory address space in different ways. E.g., performing motion estimation and motion compensation functions requires many times data accesses unaligned to word boundaries. On the other hand, Discrete Cosine Transformation (DCT) and inverse of it (IDCT) for 8 × 8 block can be performed first for rows and then for columns. Thus, transposition is needed between these two stages. Among other things, parallel memory architecture can provide a solution for these tasks. In our other paper, we shortly surveyed parallel memory architectures and proposed parallel memory architecture designs for different data path widths for video coding applications. In this paper, we construct video coding function examples by using the proposed parallel data memory efficiently. Furthermore, performance and implementation cost of the parallel memory architecture are estimated and compared to more conventional memory architectures. The examples are given for different data bus widths (16, 32, 64, and 128 bits). We show that the parallel memory can keep the data path fully utilized in many video coding function implementations. This ensures high-speed operation and full utilization of the processing resources.     

两种实时、低码率视频编码的运动估计搜索算法

先提出实时、低码率视频编码对运动估计搜索算法在运算时间和准确度上的要求，总结归纳了钻石搜索法和两步法的具体算法，通过与几种经典算法作比较，说明这两种算法更优，更适合用于实时，低码率视频编码，最后，以H．263的实现为例，说明了钻石搜索算法的具体实现。     

从H.261到H.264看视频编码标准的进展

介绍了H．26x系列视频编码标准的发展状况及其特性，对H．264的编码性能进行了分析测试，并对H．264编码的主观图像质量和亮度峰值信噪比与H．263的相关性能进行了比较和分析。