Temporal Manipulation and Sharing of Presentation State in Browser-Embedded Multimedia Documents

This paper describes an approach to defining, manipulating and sharing state variables between a web browser and a multimedia presentation engine in functionally compound XML-based documents. This framework, which we call smilState: the SMIL XML State Architecture, is a fully declarative approach to sharing state without the need for extensive scripting. The state variables in smilState are defined using standard Web technologies such as XPath, XForms and XSLT, which have been integrated with a SMIL-specific temporal component. The smilState architecture enables interactive, user-centered applications to be created that allow temporal semantics that extend beyond the facilities currently available for integrating a conventional (X)HTML browser interface with SMIL, SVG or HTML+Time content. The primary benefit of this work is that it adds a controlled temporal dimension to existing state architectures that is free of document scheduling side effects within the multimedia content. This paper provides a use cases for temporal sharing of state across documents, it describes the smil- State architecture in detail, and it describes an implementation of smilState within the open-source Ambulant SMIL player.