The fast evolution of digital technology in the last decade has deeply transformed the way by which information, notably visual information, is generated, processed, transmitted, stored, and finally consumed. The need for standards in this technological area comes from an essential requirement relevant for all applications involving communication between two or more parts: interoperability. The existence of a standard has also important economical implications since it allows the sharing of costs and investments and the acceleration of applications’ deployment. Among the most relevant standardization achievements in the area of media representation are those by ISO/MPEG and ITU-T, some of them jointly developed such as MPEG-2/H.262. Standards are typically the repositories of the best technology and thus an excellent place to check technology evolution and trends.

The ISO/MPEG standardization committee has been responsible for the successful MPEG-1 and MPEG-2 standards that have given rise to widely adopted commercial products and services, such as Video-CD, DVD, digital television, digital audio broadcasting (DAB) and MP3 (MPEG-1 Audio layer 3) players and recorders. More recently, the MPEG-4 standard is aimed to define an audiovisual coding standard to address the emerging needs of the communication, interactive and broadcasting service models as well as of the mixed service models resulting from their technological convergence. Following the same vision underpinning MPEG-4, MPEG initiated after another standardization project addressing the problem of describing multimedia content to allow the quick and efficient searching, processing, filtering and summarisation of various types of multimedia material: MPEG-7. After the development of the standards mentioned above, MPEG acknowledged the lack of a “big picture” describing how the various elements building the infrastructure for the deployment of multimedia applications relate to each other or even if there are missing standard specifications for some of these elements. To address this problem, MPEG started the MPEG-21 project, formally called “Multimedia framework” with the aim to understand if and how these various elements fit together, and to discuss which new standards may be required, if gaps in the infrastructure exist.

In a similar manner, ITU-T defined standards such as H.261 and H.263 for videotelephony and videoconference over different types of channels and it has just finished to develop, jointly with MPEG, the H.264/MPEG-4 AVC Advanced Video Coding (AVC) standard. This new standard should provide further significant improvements in terms of (frame-based) coding efficiency. These MPEG/ITU-T join developments highlight the convergence of technologies for media representation, independently of the transmission and storage media and, most of the times, of the application and business models involved.

Research on visual representation is currently mainly addressing requirements related to the growing heterogeneity of networks and terminals, the acceptance of higher codec complexities, and the needs to easily adapt to bandwidth variations with graceful degradation, to provide robustness under best effort networks, and to improve copy protection mechanisms, as well as the always-present requirement of increased compression efficiency. Wavelet based video coding, and in general (fine granularity) scalable video coding, multiview video coding, as well as multiple description and distributed video coding are among the most interesting research topics these days.

This talk will address the evolution and current status of visual representation technologies and standards as well as the most relevant emerging developments and trends.