User`s guide

VidServer and VidClient could be used as the basis for a central hub for controlling video wall
links. VidServer and VidClient could include a menu item and/or a button to force close a connection
or reinitiate a connection, which would be useful if there were connection problems. VidServer could
poll its connections to ensure that the connection was still up, and automatically disconnect any
clients that did not respond within a certain time. This would solve the problem of having to
manually close and relaunch VidServer if the TCP/IP connection is lost.
Another minor change would be to improve the format of the preference files. Currently, if the
preference files do not conform to the correct format, settings will be set incorrectly. A better format
would be to use something like PORT = 2000 instead of just 2000, which would allow settings to be
written in any order. Another improvement would be to add a Preference dialog to the VidClient
and VidServer applications, allowing administrators to adjust settings without having to quit the
application or edit text files.
Another possible addition would be to not only log the events in a window, but also write the
events to a file. This log file could then be archived and would be useful for statistical purposes. For
example, it would be possible to calculate when the system is being used most, and for how long it
was used in a given time period.
The automatic link switching application could be incorporated into VidServer, since it is already
partially implemented. In addition, VidClient could show a list of possible video links, and users
could arrange the links in order of preference, or even to manually make a connection to another video
link, even if that link was already connected to another node. This would be useful for a situation
such as a meeting, since the two nodes to be connected are known in advance. As mentioned in
Section 5.1, VidServer would need to be modified to allow more than two clients connecting to it.
Some parts of the video recording application could be built into VidServer or VidClient, such as
a “record” button. However, a separate application would be more appropriate for playback tasks.
Such an application could feature a VCR-like interface, with buttons for record, play, stop, fast
forward and rewind, as well as a time display. However, more research needs to be undertaken in
order to access the MPEG video data and write it to a file so that it can be played back.
An application to remotely control the camera could be built into VidServer and VidClient, but
again, this might be better implemented as a separate application. A camera control device (such
as the Panja F117 Stealth 1) first needs to be purchased for each camera to be controlled, and
modifications need to be made to the cameras so that they can be attached to the controller. The
controllers use the AXLink protocol, which can be obtained from Panja.
The application would need to be split into client and server components, and would behave
similar to VidClient and VidServer. The “camera controller” client would need a user interface —
perhaps a horizontal slider for “pan”, a vertical slider for “tilt” and another horizontal slider for
“zoom’. Each client would send a numerical value to the server whenever a slider was changed,
which would in turn send it on to the other client. That client would then generate the appropriate
AXLink commands, and send them, via the serial port, to the camera control device.
More research needs to be done on the protocol used by the QuickBeam infra-red drivers before
the infra-red tunnelling application can be completed. If the protocol were implemented, this would
open up the possibility of using infra-red devices as remote controls. For example, an application
could be written for PalmPilots that uses IrDA messages to remotely control the camera.
As mentioned in Section 4.7, a separate computer could be installed beside the VAN to handle
camera control tasks, and allow people to access the camera control software. This computer could
also run the infra-red tunnelling application, providing easy access to the infra-red transceiver.
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