Coding for Multimedia Sources and Sensor Data: New Theory, Algorithms, and Applications

信源编码在许多现代数字系统中起着至关重要的作用。事实上，作为一个研究领域，信源编码比以往任何时候都更加重要和丰富，数字世界中多媒体和传感器数据的日益普及带来了大量新的机遇和挑战。这项研究在这一领域追求一套特别有趣、新颖和及时的指导，旨在影响实际系统的设计。在理论、算法和应用三个方面相辅相成，在理论方面，重点研究了分布式信源编码问题。人们对这类问题的兴趣有了很大增长，其动机是，例如，需要在网络中采用量化和压缩技术来提高资源效率。该研究追求分布式信源编码理论中一个重要但在很大程度上未被探索的方面：如何在此类问题中利用失真辅助信息--即关于待编码信号分量的相对重要性的信息。在算法领域，重点是Turbo量化-低复杂度迭代信源编码技术及其实现。在过去的十年中，在开发用于纠错码的低复杂度迭代信道译码算法方面取得了巨大的成功。通过对偶原理获得的相应源代码有可能类似地改变信源编码的实践。最后，该研究调查了重要的新兴决策系统应用，其中信源编码和失真标准发挥了不可或缺的作用，但以非传统的方式。具体的例子包括散列系统、公式媒体数据库和用于认证多媒体内容的系统。

ABSTRACTSource coding plays a critical role in many modern digital systems.Indeed, as a research area, source coding is more important andfertile than ever, with a wealth of new opportunities and challengesarising from the increasing pervasiveness of multimedia and sensordata in a digital world. This research pursues a set of particularlyinteresting, novel, and timely directions in this realm, and aims toimpact the design of practical systems. There are three complementaryaspects to the research: theory, algorithms, and applications.In the theory area, the emphasis is on problems of distributed sourcecoding. There has been strong growth in interest in such problems,motivated by, for example, the need for resource efficientquantization and compression techniques in networks. Theinvestigation pursues a substantial but largely unexplored aspect ofdistributed source coding theory: how distortion side information--- i.e., information about the relative importance of the signalcomponents to be coded --- can be exploited in such problems.In the algorithms area, the focusses on turbo-quantization ---low-complexity iterative source encoding techniques and theirimplementation. Over the past decade, there has been a tremendoussuccess in developing low-complexity iterative channel decodingalgorithms for use with error-correction codes. The correspondingsource codes obtained via duality principles have the potential tosimilarly transform the practice of source coding.Finally, the research investigates important emergingdecision-system applications in which source coding anddistortion criteria play an integral role, but in nontraditional ways.Specific examples being pursued include hashing systems formultimedia databases and systems for authenticating multimediacontent.