MPEG-21: Enabling Universal Multimedia Access
Content has become a valuable asset nowadays and a variety of novel services in the entertainment sector have emerged to bring new revenue streams to the involved business entities. In the emerging Cross-Media world with a variety of mobile or fixed end-user devices, using diverse transmission channels that require distinct packetization schemes and different per case allowable bandwidth, the core question still stands: How can the same content be transmitted via different channels and consumed at various terminals without costly re-processing and re-production under specific QoS requirements, dictated both by content/service providers and end-users? Media providers are faced with two choices: either select the most appropriate device for their content and tailor the consumer experience and business models to take advantage of this specific environment, or, alternatively, invest in multiple devices, transmission channels and content formats and free the consumer experience from concerns of appropriate terminals use or specific network access. The aim of this lecture is to give an introduction to the emerging needs for universal multimedia access and to present the MPEG-21 standard and its underlying concepts that form the basis for the design of context-aware and content adaptable systems aiming at implementing the UMA aim.