User`s guide

4.7 Camera Control
Originally, the camera had been mounted on the wall, but since the camera repositioning, it is now
set, recessed, in the wall. Some modification would be required to add the possibility of camera
control, which is yet to be implemented.
There are three ways to control a camera: pan, tilt and zoom. Panning refers to swivelling the
camera about its x-axis (left-right), tilting refers to swivelling the camera about its y-axis (up-down)
and zooming refers to magnification. The modification would involve replacing the camera set in
the wall with a camera on a small wall-mount with a motorised camera controller.
Panja (formerly AMX Corp.) is a company that manufactures camera controllers. These are
small motorised Some are designed for computer control, for example, the Panja AXB-F117 Stealth
1 Camera Controller (Panja 2000). This camera controller connects to the proprietary AXlink data
bus, or an RS-232 connection, which enables communication with PCs. The VAN is equipped with
AMX control (First Virtual 2000), and thus can be used to directly control cameras.
Hardware interfaces (for example, the Panja AXB-CAM) can be used in conjunction with a
camera controller to adjust the camera’s pan, tilt and zoom. A software user interface based on
these hardware interfaces would need to be designed to allow similar functionality, and a internet
protocol would be needed to send the commands to the remote camera controller.
The implementation of a user interface would require some level of access to the VAN. Currently,
the VAN is locked in a case, and can only be opened by administrators. Perhaps the administrators
would also be responsible for allowing use of camera control, or a separate computer could be set
up for this task, leaving the VAN to do its primary tasks.
4.8 Video Recording
Video can currently be captured by substituting video camera recorders for the cameras currently
in place, and setting the video cameras to record to tape. However, this requires much human
intervention. A better solution would be for software to intercept the video as it is being transmitted
and to save it to disk as an MPEG file.
An application to record video and audio from a video link (and play it back) has yet to be imple-
mented. This would be useful for capturing meetings, but would not be used for the staff common
rooms. A method for synchronising the video from the two cameras (one at each location) would
be required, and could be achieved using a client/server model as used by the videoconferencing
reciprocity application, if each VAN captured their own video. If each (or just one) VAN captured
video from both cameras, a synchronising application would not be required. Issues such as disk
speed and real-time video encoding would also need to be addressed.
Some people may be wary of being captured, and would like to know when video recording is
taking place, so some visual indication could be displayed on the video wall when recording is in
progress. For example, a flashing red circle could be displayed in the top-right corner of the video
wall, to simulate the behaviour of a consumer video camera when in recording mode. This recording
indicator would have to be displayed on both video walls, even if only one side was recording the
video. This information would need to be communicated to both VANs, and would require a simple
internet protocol. Any visual feedback would not be captured to disk — it would just be overlayed
on the live video projection.
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