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Report on Digital Convergence Conference

"Digital Convergence: The Future of the Internet and World Wide Web"

The British Computer Society Computer Graphics & Displays Group held an international four-day meeting on this theme in Pictureville, National Museum of Photography, Film & Television, Bradford, UK, 20 - 23 April 1998. The Conference was co-sponsored by the Computer Graphics Society, Virtual Reality Society, and the Computing Suppliers Federation. Countries represented at the Conference included Belgium, Denmark, France, Germany, Japan, Netherlands, Italy and the UK.

There is substantial current interest in the convergence of computing, telecommunications, television and broadcasting, and the impact on the evolution of the Web. Media organisations can put their information on network servers and periodically update it. Users download what they are interested in. Tools and techniques for accessing, interacting with, and displaying media information are on the increase. Strategies for overcoming bandwidth limitations are needed. VRML and Java are supporting new types of environment on the Web which are extending the uses and applications of networks, and are generating a lot of excitement about the future. This Conference addressed a number of these themes.

The Conference was opened by the Vice-Chancellor of the University of Bradford, Professor David Johns CBE.

The Keynote Speaker at the Conference, Prof Dr Jose Encarnacao, Director Fraunhofer IGD, Germany, presented experiments and applications of 3-, 4- and 5-sided CAVES. The use of virtual reality in the manufacturing industry benefited from real-time, interactivity, and immersion (for navigation and exploration). Most applications have found difficulty with Head Mounted Displays and BOOM technology because of the user interface problems that are created. Virtual Tables (e.g. Workbench) allow better freedom of movement but need better price/performance particularly if they are to make inroads into the traditional 2D desktop environment. An economically priced 2D Cave would be useful in a range of applications.

Applications of Caves included industrial engineering, medical training, and marketing. Particular examples include design review, functional analysis, ergonomics, assembly planning, plant design, and entertainment. The design area had the challenges of complex models, and graphics quality. Parts assembly needed 2-handed interaction and also voice input. Plant design supported training in hazardous environments. Ship construction (Bloom and Voss) had allowed the development of a new interaction paradigm. In the area of entertainment a major contribution had been made in the development of a virtual underwater world for EXPO96 in Lisbon as part of an aquarium simulation to allow visitors to "follow" a virtual fish of their selection.

In the area of virtual prototyping, a simulated wind tunnel had been used in the development of the new Volkswagen car. Cockpit components and evaluation of air circulation had been modelled for BMW. Assembly paths had also been optimised via the Cave. Virtual humans had also been integrated into the virtual environment to allow a virtual trainer to guide real users for training purposes.

It is clear that the greater the number of sides in the Cave, the greater the integration of the user into the virtual environment. However, for applications requiring force feedback it is not yet clear how best to do this in a Cave.

The advantages of the Cave are:

The disadvantages of the Cave are: Future work will include haptic feedback and video-based tracking to avoid the use of wired links. (Further information on the work of the Fraunhofer Institute may be found in "Fraunhofer Institute: Building on a Decade of Computer Graphics Research", R A Earnshaw, IEEE Computer Graphics and Applications, Vol 18, No 2, pp 10 - 16, March/April 1998).

Prof Charles Sandbank, Broadcasting Technology Advisor, Department of Trade and Industry, outlined the challenges for convergence caused by the developments currently taking place in broadcasting. In Europe there are 40 TV channels. We expect to have 1000 satellite channels and 100 digital terrestrial channels by the year 2000. In addition, there is cable and telephone and also the Internet as a broadcast continuum. There is a spectrum of delivery and viewing ranging from the traditional public service broadcaster with millions of viewers via television to the single PC user/viewer. The move towards interactive television will tend to blur the distinction between TV and PC. Standardisation activities via ITU, IETF, and DVB are seeking to come to terms with the future. Network dependent aspects have to be separated from network independent aspects.

DVB is a market-led initiative to standardise digital broadcasting worldwide. It was formed in September 1993 and covers DVB-S (satellite), DVB-C (cable), and SMATV.

For DVB in the home, interactive services needed network independent protocols, guidelines for users, network dependent elements, and future links via VSAT and terrestrial.

The multimeda home platform needed to support an increasing number of proprietary APIs and interoperable facilities.

The EC ACTS INTERACT project is investigating interactive television return channel standardisation and trials for both terrestrial UHF and cable transmission systems. It is the intention of the project to follow the market requirements of key market sectors, including the technical developments within DVB and DAVIC. A key aspect of the project is the development of demonstration hardware to implement a terrestrial return channel. This will enable a performance and cost evaluation to take place, and for this to be compared with comparable delivery systems such as Cable and PSTN networks.

INTERACT will result in MAC layer specifications, modulation and demodulation using SFDMA and UHF upconverter.

A further EC project, ATLANTIC, is investigating low bit rates and networked transmission over integrated communication systems for advanced television. The project aims to assemble a service trial of an audio-visual programme based entirely on the MPEG-2 coded bit-stream in the context of EXPO98 in Portugal. It is envisaged that the project will deliver an end-to-end programme chain based on the MPEG-2 coded bit-stream throughout, thereby avoiding the quality impairments arising from the current practice of repeated encoding and decoding.

It is expected that the project will lay the foundations for the economic production of television programmes in an era when the number of television channels will be increasing dramatically. Through the development of equipment using strategic VLSI devices, the functionality required for handling the MPEG bit-stream in programme production and distribution should become available at reasonable cost. The technology developed should find use in both professional and consumer-based applications.

With regard to regulation issues in the broadcast arena, Europe needs to know when it can act and when the members states can do things more efficiently themselves. The overall goal is "TV without Frontiers".

Digital terrestrial TV plans in the UK involve 6 multiplexors at 24 Mbits/sec each. MHEG5 (Multimedia Hypertext Experts Group) is also involved. Interactive capabilities will be offered for TV programmes such as "Question Time" to allow the viewers to be polled for their opinions on issues. Specifications for the units have been agreed and will be implemented later this year.

BBC Interactive will allow the viewer to control the area of the country they wish to see highlighted (e.g. for detailed weather information). BBC Plus will allow the viewer to display biographical or other associated information with the programme they are watching. Information about the bands and players will be provided for Top of the Pops. The Clothes Show will have background information on shops and options for the clothes. Sport programmes (e.g. tennis, football, music) will allow the viewer to select the games or musicians they want to watch and also the preferred camera angles they wish to view from.

It is clear that the PC is not a straight alternative option for the TV since the way information is presented and viewed is different. For example, users sit on average about 1.5 times the picture height from the PC whereas they sit 8-10 times the picture height from the TV.

Creating a link from Internet Services to TV (e.g. Web TV) was not very good for supporting millions of people (i.e. home viewers of television). A direct link from Broadcasting to Laptop was not so easy for portable devices. Internet was not very good for communal interaction (e.g. interactive TV programmes) because of the load on the network and slow speed lines into homes.

Interestingly, the largest Web site in Europe with the most accesses is BBC Online.

Convergence is progressing rapidly. Standards are catching up with the reality of the situation. Regulation is complex and will become more so. Human computer interface issues need attention so that interactive services are user-friendly (most people find the VCR difficult to use!). Major changes in the commercial scene are expected and the social implications are likely to be considerable.

Dr Mikael Jern (Vice-President, AVS/UNIRAS) outlined the pros and cons of 'thin' versus 'fat' visualization clients. Keeping the source data on a remote server and transferring via HTML, GIF, or VRML allows 'graph on demand' and the opportunity to use the anchor mode in VRML to hyperlink to further data.

An ESPRIT Project, INDEX (Intelligent Data Extraction) is investigating ways to access data and information between clients and servers. Partners in the project include British Aerospace, Daimler Benz, AVS/UNIRAS, University of Manchester, RUS and OGS.

Smart Word documents can now include Active X components which can then be accessed by their recipients.

Prof Peter Gibbins, Director of the Digital VCE (, discussed the development of "Virtual R&D". A useful reference in this connection is Third Generation Research and Development P Roussel, K N Saad, T J Erickson, Harvard University Press.

The three generations are as follows:

Abstract research (i.e. ivory tower R&D)
Project based R&D (1945 onwards)
Strategic R&D.

Fourth generation R&D is summed up in "Diffusion of Innovations", E M Rogers, and has the following characteristics:

The initiation and development of the two national Virtual Centres of Excellence in the UK were outlined. The first, on Mobile and Personal Communications concentrated on telecommunications. The second is on Digital Broadcasting and Multimedia Technology.

The Communications panel of the Technology Foresight exercise highlighted the need for a high-profile centre for long-term, cutting edge academic research into broadcasting and multimedia technology. It was considered critically important for the UK to have a central focus for its research in these vital areas.

A group of companies and six leading universities have therefore come together to provide the expertise capable of researching and developing the future operation of multimedia and digital broadcasting technologies.

The Centre will be virtual in that research will be carried out on a number of sites using existing facilities, and with extensive use of electronic communications to which the industrial partners can connect their own research centres. The Centre will provide a mechanism for rapid creation of a critical mass of research at shared costs, it will create a wide, cross-disciplinary interface with other fields of research in each university, and will offer opportunities for universities to develop longer-term relationships and more effective access to resources.

The Centre will take forward a core programme of long-term research into the technologies that underpin broadcasting and multimedia and will be largely funded by, and relevant to industry, although it will not be near to market. The precise programme will be defined by the members, although it is likely to be narrow enough to enable in-depth research to be effective and wide enough to attract broad industrial support. Areas under consideration include content creation, production and post-production, service creation, transmission and user interfaces.

To date, 12 companies and agencies have indicated their wish to join the VCE: BBC, BT, Digi-Media Vision, Mitsubishi, Pace, Panasonic, Philips, Racal, Radiocommunications Agency, S4C, Snell & Wilcox and Sony. Membership remains open to additional companies.

The university partners comprise the Universities of Bradford, Bristol, Essex, Surry, University College, London and a joint research group of the University of Cambridge, Imperial College, and the National Film & Television School.

Three projects have already been started in the areas of scalable multidimensional data, virtual rehearsal, and content-based recognition and retrieval. Virtual rehearsal is an area where new kinds of collaboration are being explored, since it is important that cues and gestures that make acting work in the real world, have to be highlighted in the virtual world and not suppressed by technology. In addition, interaction and sharing via virtual objects and characters (e.g. avatars) would allow disabled people to participate more fully in areas that hitherto they have been excluded from.

A further funding programme DTI/EPSRC LINK Broadcasting initiative has also been initiated and a first Call for Proposals is currently being evaluated.

Prof Marc Cavazza (University of Bradford) discussed the issue of what content is and how digital convergence will affect this. Content is an ill-defined concept and allowed the views of the broadcasters to dominate. New methods of broadcasting such as the Web will tend to change this. Current cultural objects tended to follow traditional lines of authoring and publication. Convergence changes the status of this by bringing in new cultural objects specific to the digital age, such as Web pages, video games, etc. New schemes for authoring and distribution are being implemented. For example, extended authoring, hyperlinks to other documents, and possible new kinds of digital cultural object are now increasing. Virtual environments and telepresence allow users to share experiences. New kinds of authoring and storytelling may bring about a merging of virtual environments and cinema.

The Web has reintroduced the document structure into the digital age but has posed new problems for our understanding. For example, what kind of cultural object is a Web-TV page? How does this affect the user's appropriation of it? Are we watching TV when we read narrative text and interact with it, or are we reading TV?

New kinds of visible knowledge ('knowlets') are being created by new media. Access is possible through concepts rather than experiences. Agent ontologies are static; visible knowledge will consist of dynamic and causal models.

Interactivity deconstructs the relationship between users and distributed cultural objects and leads to a world of 'push' experience-based media. On the other hand, intelligence promotes new forms of cultural objects - 'pull' - with persistent information. There is a tension between these two paradigms.

David Leevers (BICC) outlined current work in Europe on shared virtual experiences across networks. The recent Green Paper on convergence highlights the challenge. The service environment is changing. Optimising individual services will no longer work. All services interact and all share a continuously changing environment. The work of the Telepresence and Shared Virtual Environments Chain (T&SVE) was outlined. A new ACTS project, ASIS (Alliance for a Sustainable Information Society) was seeking to identify the issues which would result in an overall beneficial effect in the utilisation of information to support a better quality of life.

A number of pan-European projects are concerned with virtual working, collaborative design, shared environments, telerobotics, remote scene reconstruction, and distributed video. The use of networks has brought together researchers, developers, designers and users into a shared space within which developments have been accomplished. The extent to which local and real experiences have been effectively replaced by remote and distant interactions with multiple groups of participants has been quantitatively analysed. Inclusion of remote participants over networks also represents added value to the local group expertise and this has also been analysed and quantified. A series of generic guidelines for the use of telepresence and shared virtual environments has been defined as a result of this work.

A framework model of shared virtual working is also being constructed which enables the results of particular projects, experiments and scenarios to be understood within a larger context of persistent multimedia communications environments. These are becoming increasingly ubiquitous as the power and functionality of networks and interfaces increases.

This framework is intended to define the paths between one communication type and another and also the changes that are needed in moving from one form of communication to another. The functional stages in the cycle: rehearsal, navigation, exploration, discussion, collaboration, persuasion and acceptance are generic entities which not only describe cycles within the local environment but also support tele- and virtual communications over a wide range of time-scales and life cycles.

A conceptual architecture for future communications technologies and services is being constructed. The relationship of this architecture to current network-based virtual environments and future Web-based virtual worlds is also being investigated.

The Telepresence and Shared Virtual Environments Chain addresses the critical aspects in the design, implementation and successful application of shared virtual environments including architecture, devices, standards, networks, interaction and sharing, telepresence, modelling, and cost/benefit analysis.

The Chain brings together results from a number of European projects concerned with virtual working, collaborative design, shared environments, telerobotics, remote scene reconstruction, and distributed video. These networked technologies are already allowing researchers, developers, designers and users to enter a shared space within which work can be done.

The extent to which local and real experiences have been effectively replaced by remote and distant interactions with multiple groups of participants is being quantitatively analysed. Inclusion of remote participants over networks represents added value to the local group expertise and this is being studied in several of the projects.

A series of generic guidelines for the use of telepresence and shared virtual environments will be defined as the ACTS projects reach their conclusions.

A framework for shared virtual activities has also been constructed. This enables a range of scenarios to be understood within the comprehensive context of persistent multimedia communications environments. Such environments are becoming increasingly ubiquitous as the power and functionality of networks and processors increases.

This framework is currently known as "the cycle of cognition". The cycle defines the paths between one communication type and another and also the changes that are needed in moving from one form of communication to another. The functional stages in the cycle are: rehearsal, navigation, exploration, discussion, collaboration, persuasion, and acceptance. These are generic entities that have to be supported by tele- and virtual communications over a wide range of time-scales and life cycles if the networked part of the everyday environment is to be as ubiquitous and persistent as it needs to be.

Carlton Reeve (University of Bradford) outlined the benefits and challenges of virtual rehearsal. Currently actors practice with the script in isolation and only come together on the real set at the last minute. Virtual rehearsal offered the following advantages:

The challenges and difficulties faced by virtual rehearsal include: On the other hand, the rehearsal collaboration does allow the director to have a clear view of how the rehearsal is going at an earlier stage than normal. In addition, the director can view the rehearsal from any angle, which is useful for theatres with audiences on four sides.

Kieran O'Hea (TechServ) outlined the EC 5th Framework Programme 1998 - 2002 "Creating a User Friendly Information Society". For the area of Information Society Technology (IST) 3.9 billion ECU had been assigned. The emphasis would be on generating creative content, managing multimedia content, and delivering personalised content.

Prof Stephen Molyneux (University of Wolverhampton) discussed the future applications and challenges of convergence. New kinds of services and interactive applications in the world of tomorrow need:

Pre-Conference Courses on 20 - 21 April presented the following topics:
Introduction to Multimedia on the WWW
Introduction to VRML
Design and Layout for Web Sites
Digital Image Coding for Media Services
Introduction to Java Programming
Information Visualization on the Web
Topics in Computer Animation
Ontologies and Content Description in MPEG-7
Software Engineering of Autonomous Client and Web Spiders using SMTP and HTTP.
(to be continued in the next issue)

Rae Earnshaw