SMIL State: an architecture and implementation for adaptive time-based web applications

In this paper we examine adaptive time-based web applications (or presentations). These are interactive presentations where time dictates which parts of the application are presented (providing the major structuring paradigm), and that require interactivity and other dynamic adaptation. We investigate the current technologies available to create such presentations and their shortcomings, and suggest a mechanism for addressing these shortcomings. This mechanism, SMIL State, can be used to add user-defined state to declarative time-based languages such as SMIL or SVG animation, thereby enabling the author to create control flows that are difficult to realize within the temporal containment model of the host languages. In addition, SMIL State can be used as a bridging mechanism between languages, enabling easy integration of external components into the web application. Finally, SMIL State enables richer expressions for content control. This paper defines SMIL State in terms of an introductory example, followed by a detailed specification of the State model. Next, the implementation of this model is discussed. We conclude with a set of potential use cases, including dynamic content adaptation and delayed insertion of custom content such as advertisements.

Dick C. A. BultermanEmail:

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Jack Jansen   Is a researcher at Centrum Wiskunde en Informatica (CWI), with over 25 years of experience in multimedia and distributed systems. Empowering people to put available technology to a use they themselves envision is his driving principle. This results in activities ranging from languages, such as Python, via web standardization work (SMIL, Rich Web Application Backplane) to implementing systems for accessible and reusable multimedia (Ambulant). Recently, he has finally started to pursue a PhD. Dick Bulterman   Is head of distributed multimedia systems research at CWI, the Dutch national center for mathematics and computer science in Amsterdam. He is also a professor of computer science at the VU University in Amsterdam. Dr. Bulterman received his Ph.D. in computer science from Brown University in Providence RI (USA) in 1981. He has been co-chair of the W3C working group on synchronized multimedia since 2007; this group released the SMIL 3.0 Recommendation in late 2008. Bulterman has been active in the Document Engineering community since 2005. He is past program chair and past general chair of the ACM DocEng Symposium. He is also past chair of ACM Multimedia of and IEEE ISM. Dick Bulterman lives in Amsterdam with his wife and two children.