Multimedia Systems (2002) 8: 295–314 Multimedia Systems � Springer-Verlag 2002 c JINSIL: A middleware for presentation of composite multimedia objects in a distributed environment Junehwa Song 1 , Asit Dan 2 , Dinkar Sitaram 3 1 EECS, Korea Advanced Institute of Science and Technology, 373-1, Kusong-dong, Yusong-gu, Taejeon, 305-701 Korea e-mail: junesong@cs.kaist.ac.kr 2 IBM T.J. Watson Research Center, Yorktown Heights, NY 10598, USA e-mail: asit@us.ibm.com 3 Andiamo Systems, India; e-mail: dsitaram@andiamo.com Data Transfer Abstract. In a distributed environment, the presentation of Rate (Mb/s) structured, composite multimedia information poses new challenges in dealing with variable bandwidth (BW) require- Swimmer 5 ments and synchronization of media data objects. The de- Swimmer Maximum BW 2 tailed knowledge of BW requirements obtained by analyz- Semi−final statistics 4 2 ing document structure can be used for efficient utilization Swimmer Final statistics 3 of system resources. A distributed multimedia environment Swimmer 1 Available BW consists of various system components that are either dedi- 2 1 cated to a client (e.g., client buffer space and BW) or shared Semi−Final Final across multiple clients (e.g., server buffer space and BW). A 1 Global view Global View shared server could benefit from fine granularity advanced Time (sec) reservation of resources based on true BW requirements. 10 60 80 95 140 155 Prefetching by utilizing advance knowledge of BW require- Fig. 1. Olympic swimming competition ments can further improve resource utilization. The prefetch schedule needs also to be aware of the BW fragmentation Simthsonian 2 Data Transfer in a partitioned server . In this paper, we describe the JIN- Rate (Kb/s) Simthsonian 1 SIL middleware for retrieval of a composite document that takes into account the available BW and buffer resources and the nature of sharing in each component on delivery paths. House Capitol Maximum BW White It reshapes BW requirements, creates prefetch schedules for US efficient resource utilization, and reserves necessary BW and buffer space. We also consider good choices for placement of prefetch buffers across client and server nodes. Narration Narration Available BW Narration 28.8 2 1 3 20 Pastorale Time (sec) 10 40 70 120 1 Introduction Fig. 2. Tour of Washington, DC The rapid evolution of multimedia technologies has made feasible new ways of creating and presenting complex multi- media documents. Such documents consist of media objects An efficient presentation of such structured, composite of various types and granularities that are organized into multimedia information (i.e., retrieval and synchronous play- meaningful chunks; for example, a slide presentation or a back) gives rise to new challenges. In a distributed multime- story consisting of multiple (and even simultaneous) images, dia environment, some or all pieces of a composite presen- text data, as well as video and audio clips [10, 15, 20, 24]. tation object may reside in one or multiple remote systems Two examples of such composite presentations and resulting away from client presentation systems (see Fig. 3). To avoid variations in the data consumption rates are shown in Figs. 1 jitter in a presentation, appropriate resources need to be re- and 2. The first example is a report of a swimming compe- served on various data paths from the respective sources tition where, in addition to the global view, small video to the client systems [2, 3, 6, 8, 11, 12]. For a composite windows containing close-ups of the leaders are shown to- document, the instantaneous total data consumption rate that ward the end of the report. The second example mingles needs to be supported will vary over time depending on the audio, images and narration of the interesting sights around structure of the presentation [16, 17]. Table 1 shows the data Washington, DC (details are provided later). consumption rates for the above two presentation examples.
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