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An integrated approach to technology within Lecture Room Services
2 Lecture Theatre 2
The specialised needs of video-conferencing had to be addressed specifically. There are several areas that require particular attention.
It was decided that the only practical position to permanently mount cameras was on the side wall of the lecture theatre. These positions would allow reasonable coverage of the front of the room including the lectern, but it would also be possible to pan the cameras round to give acceptable coverage of the audience seating area. Three-Chip cameras were specified in order to give high quality pictures in the less that ideal lighting conditions.
Sound is often difficult to manage in a video-conferencing environment. In ISDN based conferencing, there is a delay involved in processing the video and the sound is correspondingly delayed. This can give rise to an echo as the far-end sound is picked up by the local microphone and returned again to the far end. Normally this problem is dealt with by sophisticated echo-cancellation hardware either within the video-conferencing codec, or within a separate 'black-box'. In the case of the proprietary system used in the SMVCN, there is no such delay. Instead, the problem of far end sound being picked up and set back to its source can give rise to audio feedback. To eliminate this problem, very stringent acoustic performance criteria are laid down for SMVCN studios. Very detailed empirical trials were necessary to achieve these criteria in the lecture theatre environment.
High quality lighting is hard to achieve in this environment unless a very high powered projector is used. As budgets precluded this, a lower output device had to be used but this required that the room lighting be dimmed to achieve satisfactory results. As a result, in order to provide enough light for the cameras, the main speaker's area had to be lit with a pool of light which would not spill onto the projection screen. This entailed the use of focused spotlights and careful attention had to be given to the overall lighting balance to avoid discomfort to the presenter. Additionally, there are considerable problems associated with sending a satisfactory shot of the audience to the remote site. The room lighting must be brought up to enable an acceptable picture. However, this prevents high quality projection. One possible option is to automatically bring up the room lights for the duration of the audience shot. The can be achieved by linking a camera pre-set scene to a pre-set lighting state using the room control system.
Finally, very flexible control of the video-and audio switching must be achievable. It must be possible to send one source to the far-end, preview any source on the preview monitor and display any other source on the main screen. This switching must all be achieved synchronously, and its operation must be straightforward enough not to baffle users.
Although it would be possible to separate the normal lecture theatre room control functions from those of the video-conferencing functionality, it was decided to try to 'graft on' the video-conferencing functionality as seamlessly as possible. In this way, users would not have to learn two separate systems.
A final consideration is that of overall quality. In many ISDN based video-conferencing systems, there is extensive use of low-quality (cheap) audio-visual components. This is done on the basis that the limitations of the low-bandwidth conferencing medium will mask any aberrations. This is not so in the SMVCN. The quality of the video is much higher than that achieved in ISDN systems and the sound is of CD quality. As a result, it is important that all aspects of the signal path, from cameras and microphones to the distribution amplifiers and switching components, are carefully considered.
There is of course no reason why these higher quality components should not be used in an ISDN system. Their use will certainly not be detrimental and will allow a great degree of flexibility to change the type of codec in use as the technical quality of video-conferencing equipment continues to improve.
It was envisioned from the outset that there would be a considerable effort required to achieve even the most basic level of training required to use the new facilities. Even before the room design was complete, a statement committing to the level of support which would be provided had been circulated.
Extensive technical support will be available for academics using the theatre. In particular, staff using the room for the first time, will have access to a hands on training session where they will be taken through each section of the control system.
Initially, it is intended to provide a technician on site to deal with any problems which might occur and an on-call support system will operate whenever the room is in use. For teleconferencing it is anticipated that a technician will always be present at the start of each session.
It was felt, at all levels, that the level of support provided would have to be sufficient to prevent any lecturer being unable to complete a class. Failure to achieve this would result in academic staff deserting the room in droves. It was also thought that the earlier staff could be exposed to the system and be made comfortable with it, the more likely individuals were to consider changing their course materials to exploit the enhanced facilities.
Prior to the start of the academic term all staff members were invited to one of a series of demonstrations of the new facilities. These sessions took the form of a formal demonstration of each function available followed by a question and answer session. Staff were invited to remain behind at the end of each session and were encouraged to try the facilities out for themselves. Members of staff who were about to use the theatre for the first time were also invited to book individual hands on sessions in which they would be able to try their own material on the system. Each of these sessions was supervised by a member of AV staff.
It was thought that the majority of video-conferencing applications would require technician support in a lecture theatre environment. Because of this, specific video-conferencing training for this room was not originally offered. However, parallel training in general video conferencing methodology was available along with advice on facilitating a video-conference.
This was generated as part of the TALiSMAN project and example material included below. This comes from You and your video-conference (February 1998) produced by the SHEFC funded TALiSMAN project based at Heriot-Watt University. The full version of this training material is used in the context of a series of workshops, roadshows, and supported on-line training. This training has been made available equally to all Higher Education Institutes in Scotland. Further information about TALiSMAN and its activity can be found through its web site at http://www.talisman.hw.ac.uk/.
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