Towards a syntax for multimedia semantics

This article describes the current state of the art on representing the fouressential conceptual facets of a multimedia unit, namely the form and substance of content and the form and substance of its expression, and points to the still un solved problems regarding the syntax for media semantics. We first provide a brief overview of the general features of the MPEG-7 standard and its different parts. This serves as a description of the state of the art in content description for audio-visual media. We then analyse the ability of one of these parts for its capability to define structures for describing media semantics. We describe the problems of two currently conflicting MPEG-7 representations of expression-based media semantic, which should be equivalent. We then discuss high-level aspects of media semantics, namely the general problems of an ontology for media semantics. Finally, we talk about the problems of applying the theoretical conceptsto real applications.