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Báo cáo hóa học: " Research Article Distributed Temporal Multiple Description Coding for Robust Video Transmission"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Distributed Temporal Multiple Description Coding for Robust Video Transmission | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 183536 13 pages doi 10.1155 2008 183536 Research Article Distributed Temporal Multiple Description Coding for Robust Video Transmission Olivier Crave 1 2 Christine Guillemot 1 Beatrice Pesquet-Popescu 2 and Christophe Tillier2 1 Institut de Recherche en Informatique et Syst emes Aleatoires Institut National de Recherche en Informatique et en Automatique 35042 Rennes Cedex France 2 Groupe des Écoles des Telecommunications Departement TSI Signal-Images École Nationale Superieure des Telecommunications 46 rue Barrault 75634 Paris Cedex 13 France Correspondence should be addressed to Olivier Crave olivier.crave@tsi.enst.fr Received 22 March 2007 Accepted 6 June 2007 Recommended by Peter Schelkens The problem of multimedia communications over best-effort networks is addressed here with multiple description coding MDC in a distributed framework. In this paper we first compare four video MDC schemes based on different time splitting patterns and temporal two- or three-band motion-compensated temporal filtering MCTF . Then the latter schemes are extended with systematic lossy description coding where the original sequence is separated into two subsequences one being coded as in the latter schemes and the other being coded with a Wyner-Ziv WZ encoder. This amounts to having a systematic lossy Wyner-Ziv coding of every other frame of each description. This error control approach can be used as an alternative to automatic repeat request ARQ or forward error correction FEC that is the additional bitstream can be systematically sent to the decoder or can be requested as in ARQ. When used as an FEC mechanism the amount of redundancy is mostly controlled by the quantization of the Wyner-Ziv data. In this context this approach leads to satisfactory rate-distortion performance at the side decoders however it suffers from high redundancy which penalizes the central .