Pre- and Post-Filtering for Block-Based Image and Video Communication Systems

这项研究涉及的研究和开发的一个集成的框架，前和后过滤沿着数据块边界在基于块的图像/视频通信系统。新的框架可以被认为是一个推广，并提供了一个显着的改进，传统的块DCT编码方法在JPEG和MPEG。该研究主要针对无线手持设备中资源受限、速度要求高和实时应用的低复杂度图像/视频编码和通信算法或系统，对实际信号处理、编码和通信系统具有重要的影响。通过考虑块间空间相关性和基于局部信号内容动态地调整算子，编码效率大大提高。在解码器处，增强了感知重构质量。块效应通过沿块边界沿着进行积极的后滤波来减轻，而振铃效应通过自适应地改变算子大小来大大减少。噪声信道环境中的鲁棒性和数据恢复能力也通过空间扩展信息和通过基于通信环境和接收的相邻数据动态切换插值后置滤波器来提高。 最后，在实践方面，小型本地运算符很好地适合并行计算，快速，VLSI友好，可能无乘法器的实现。现有的基于块的基础设施可以保持完整，因为预处理/后处理在空间域之外操作。调查员探索前/后处理操作员，可以保持与目前在网络上和存档数字图书馆中提供的大量JPEG和MPEG比特流的兼容性。工作水平声明：在建议的支持水平下，PI将尽一切努力满足项目的原始范围和工作水平。

This research involves the study and development of an integrated framework of pre- and post-filtering along the data block boundaries in block-based image/video communication systems. The novel framework can be thought of as a generalization of and provides a significant improvement for the traditional block DCT coding approach in JPEG and MPEG. The investigation is particularly geared toward low-complexity image/video coding and communication algorithms or systems in resource-constrained, speed-critical, and real-time applications for wireless hand-held devices.The research is expected to have a significant impact on practical signal processing, coding and communication systems. Coding efficiency is greatly improved by taking into account inter-block spatial correlation and by adapting operators dynamically based on local signal contents. At the decoder, perceptual reconstruction quality is enhanced. Blocking artifacts are mitigated with aggressive post-filtering along the block boundaries whereas ringing artifacts are greatly reduced by adaptively varying the operator size. Robustness and data recovery capability in noisy channel environments are also improved by spreading information spatially and by dynamically switching interpolative post-filters based on the communicating environment and the neighboring data received. Finally, on the practical aspect, small local operators lend themselves nicely to parallel computing, and fast, VLSI-friendly, possibly multiplierless, implementations. Existing block-based infrastructure can be kept intact since pre-/post-processing operates outside in the spatial domain. The investigator explores pre-/post-processing operators that can maintain compatibility with the huge collection of JPEG and MPEG bit-streams currently available on the web and in archiving digital libraries.-------------------Level of Effort Statement:At the recommended level of support, the PI will make every attempt to meet the original scope and level of effort of the project.