Improving SMIL with NCM Facilities

SMIL is an XML-based language for specifying documents with temporal and spatial synchronization relationships, recommended by the W3C. However, SMIL has some limitations as a hypermedia authoring language. In order to overcome these limitations, this work presents the integration of SMIL documents with HyperProp, a hypermedia system based on an object-oriented model called NCM (Nested Context Model). As benefits, the integration makes both NCM facilities and HyperProp authoring and formatting tools available for SMIL documents. Furthermore, this work presents how the SMIL language can be extended to incorporate NCM facilities through the inclusion of new XML elements and attributes found in NCL, the NCM declarative language. Among the facilities, we can highlight the possibility of reusing document components and their presentation characteristics, offering flexibility in temporal specifications, adapting a document presentation according to user navigation and specifying n-ary relationships expressing causality or constraint among components.