Future interactive multimedia systems will exploit the opportunities offered by low-cost high-performance technology, increased communication capabilities and rapidly expanding multimedia databases. International standards such as MPEG-4 and MPEG-7 will support new methods of communication, access, and manipulation of digital audio-visual data.
The talk will review current and proposed standardisation activities in this area, with a particular emphasis on video coding techniques for object-based systems. An overview of our own work and that of some others will be given.
There are two distinct areas of work in mobility: "mobile computing", concerning computation that is carried out in mobile devices, and "mobile computation", concerning mobile code that moves between devices. These distinctions are destined to vanish. We aim to describe all aspects of mobility within a single framework that encompasses mobile agents, the ambients where agents interact and the mobility of the ambients themselves.
The main difficulty with mobile computation is not in mobility per se, but in the crossing of administrative domains. Mobile programs must be equipped to navigate a hierarchy of domains, at every step obtaining authorization to move further. Therefore, at the most fundamental level we need to capture notions of locations, of mobility and of authorization to move.
We identify "mobile ambients" as a fundamental abstraction that generalizes both dynamic agents and the static domains they must cross. From a formal point of view we develop a simple but computationally powerful calculus that directly embodies domains and mobility (and little else). The calculus forms the basis of a small-language/ Java-library. We demonstrate the expressiveness of the approach by a series of examples, including showing how a notion such as "crossing a firewall" has a direct and analyzable interpretation.
The CURSOR system is a direct application of Radio Astronomy techniques to the problem of positioning by radio, and it uses existing transmitters set up for other purposes. The high-precision CURSOR system allows metre-accuracy tracking using medium-wave pop-radio broadcasts. The GSM CURSOR pin points the location of a digital mobile phone to within 70 m or so. I shall describe and demonstrate both types using computer play-backs of recent tests in Cambridge and London.
Looking ahead to the requirements of next-generation geographical information systems (GIS), one of the extensions identified is the integration of multimedia data such as video, image, audio and unstructured text. Recent developments in the hardware and software aspects of multimedia technology have made full-fledged multimedia geographical information systems (GIS) feasible. However, these media types are currently not provided as standard built-in data types. Instead, the representation and manipulation is tailored to the individual application.
The seminar will focus on the issues involved in the provision of a suitable conceptual model to encompass all the multimedia types that currently exist. A reference architecture to provide support for the management and querying of multimedia information in GIS will be dscribed. Examples of multimedia GIS will be used to illustrate the discussion.
Much has been made in recent years of the potential value of sociological investigation for system design, particularly in the field of CSCW. Nevertheless, there is a danger that 'ethnography' becomes regarded as nothing more than careful and prolonged observation in 'real world' settings, without due regard for the contrastive analytic work done by ethnographers in regard to the relationship between 'process' and 'work'. Whilst naturalistic enquiry may in and of itself have some benefits, this talk will emphasise the distinction between 'formal' or 'idealised' conceptions of behaviour and the 'lived reality' of working life. It will draw on research experiences in areas such as Air Traffic Control, retail financial services and Information use in museums, to suggest that ethnographies are of value precisely because of their interest in 'lived reality'.
Within 10 years more than 500 satellites will have been launched capable of providing gigabit speeds on demand almost anywhere. On the ground a huge investment in infrastructure will mean that wide area high capacity communications will at last become a reality. This talk examines the economic, regulatory and technological forces which will bring about such developments.