本篇論文的目地為在分散式共享記憶體上發展一個MPEG-4平行壓縮編碼器，為了得到高的壓縮效率，需要盡可能的減少因為引線間同步所帶來的成本、執行I/O動作所造成延遲的影響、為了達到資料一致性所來的成本與資料運算的成本，為了減少因引線間同步所帶來的成本，我們使用管線程式設計的模式來減少同步點的數量，另外，我們建構了一個Twin-free的機制來減少為了達到資料一致性所來的成本，另一方面，為了減少執行I/O動作所造成延遲的影響，我們使用了主僕式的程式設計模式使計算與I/O執行時間重疊，並且我們還提出了兩層式的資料切割方法來最小化資料運算的成本，我們所提出的MPEG-4編碼器已經被實做在一個稱為Teamster的測試平台上，實驗數據顯示透過使用上面所提到的技術，在32個節點上，每個節點具有兩個Itanium II 1.5GHz的CPU並且每個節點間使用Gigabit乙太網路連結，我們所提出的MPEG-4編碼器已經成功的達到即時壓縮的時間限制。

　　The purpose of this paper is to develop a MEPG-4 parallel encoder on DSM systems. In order to get high performance, it is necessary to minimize the cost of synchronizing threads, the impact of I/O latency, the cost of data consistency and the cost of data computation as possible as we can. For reducing the cost of synchronization, a programming model of pipeline is applied to reduce the number of synchronization points. In addition, a twin-free mechanism is built to reduce the cost of maintaining data consistency. On the other hand, a master-salve programming model is employed to overlay computation and I/O in order for alleviating the impact of I/O latency. Moreover, a two-level partitioning method is proposed to minimize the cost of data computation. The proposed MPEG-4 encoder has been implemented on a test bed called Teamster. The experimental results show the proposed MPEG-4 parallel encoder has successfully met the requirement of real time via. 32 nodes, each node is equipped with dual 1.5 GHz Itanium II processors and connected by Gigabit Ethernet, through the support of previous techniques.

[1] ITU-T Recommendation T.120. Introduced to Audiographics and Audiovisual Conferencing.1996.

[2] G. Bressan, R.M. Silveira and W.V. Ruggiero; “A Framework for Distance Learning Employing Video on Web Environment”, International Conference on Technology and Distance Education, Fort Lauderdale - Florida, June/1999.

[3] P. Venkat Rangan, Harrick M. Vin, Srinivas Ramanathan. Designing an On-Demand Multimedia Service. IEEE Communications, Vol 30, No. 7, July 1992.

[4] ISO/IEC IS 13818, Information Technology-Generic Coding of Moving Pictures and Associated Audio Information, 1996(MPEG-2).

[5] ISO/IEC, “MPEG-4 Overview –(Melbourne Version)”, JTC1/SC29/WG11 N2995, Oct 1999

[6] ISO/IEC, “Information Technology- Generic Coding of Audio-Visual Objects, Final Draft of International Standard”, JTC1/SC29/WG11 N2502, Oct 1998

[7] Touradj Ebrahimi, Caspar Horne, ”MPEG-4 natural video coding- An overview”, Image Communication Journal 1999

[8] Blaise M Barney. The Message Passing Interface. Tutorial delivered at the International Conference on High Performance Computing, Seoul, Korea, April 28 - May 2, 1997.

[9] Protic, J., Tomasevic M. and Milutinovic V.,”A survey of distributed shared memory systems”, IEEE System Sciences, 1995. Proceedings of the Twenty-Eighth Hawaii International Conference on , Volume: 1 , 3-6 Jan. 1995 Pages:74 - 84 vol.1

[10] K. Li “Shared Virtual Memory on Loosely Coupled Multiprocessor,” Ph.D. Dissertation, Yale University, TR YALEU-RR-492, 1986.

[11] Leslie Lamport,” How to Make a Multiprocessor Computer that Correctly Executes Multiprocess Programs”, IEEE Transactions on Computer, C-28(9), pages 690-691, September 1979.

[12] Kourosh Gharachorloo, Daniel Lenoski, James Laudon, Philip ibbons, Anoop Gupta, and John Hennessy.”Memory Consistency and Event Ordering in Scaleable Shared-Memory Multiprocessors”, In 17th Annual International Symposium on Computer Architecture, pages 15-26, 1990.

[13] ISO/IEC, “Verification Model Development and
Core Experiments,” ISO/IEC JTC1/SC29/WG11 N1110, Nov. 1995.

[14] T. Sikora, “The MPEG-4 Video Standard Verification Model,”IEEE Transactions on CSVT, vol. 7, no. 1, pp. 19-31, Feb. 1997.

[15] T. KOGA, K. IINUMA, A. HIRANO, Y. IIJIMA, T. ISHIGURO, “Motion-compensated interframe coding for video conferencing”, in Proc. NTC 81, pp. C9.6.1-9.6.5, New Orleans, LA, Nov. Dec. 1981.

[16] Hamosfakidis, A.; Paker, Y.; Cosmas, J.,” A study of concurrency in MPEG-4 video encoder”, Multimedia Computing and Systems, 1998. Proceedings. IEEE International Conference on , 28 June-1 July 1998 Pages:204 – 207

[17] Yong He; Ahmad, T.; Liou, M.L.,”MPEG-4 based interactive video using parallel processing”, Parallel Processing, 1998. Proceedings. IEEE International Conference on , 10-14 Aug. 1998 Pages:329 – 336

[18] Miguel Ribeiro, Oliver Sinnen, Leonel Sousa,” MPEG-4 Natural Video Parallel Implementation on a Cluster”, Image and Video Coding, RECPAD2002, Page