Image Processing Reference
Large corporations have used video conferencing for many years. As far back as the 1980s,
multinational corporations were prepared to permanently lease lines from the telecom-
munications companies in order to link headquarters offices in the United States with
European offices. This generally required a dedicated room to be set aside and was suffi-
ciently expensive that only one video-conferencing station would be built per site. Only
one group of people could participate at a time, and the use of the technology was
reserved for important meetings.
Video conferencing can now be deployed to a desktop or mobile phone. This is only
possible because video compression reduces the data-transfer rate to a trickle compared
with the systems in use just a few years ago.
Video conferencing applications currently lack the levels of interoperability between
competing systems that telephone users enjoy for speech. That will come in time. For now,
the systems being introduced are breaking new ground in making this available to the
general public and establishing the fundamental principles of how the infrastructure
should support it.
Figure 2-8 shows an example of an advanced video-conferencing user interface that
supports multiple simultaneous users. This is available in the MacOS X version 10.4 oper-
ating system and is called iChat AV.
The use of remote apparatus and VR techniques for medicine is starting to facilitate so-
called “telemedicine,” where an expert in some aspect of the medical condition participates
in a surgical operation being performed on the other side of the world. Clearly there are
issues here regarding the need for force feedback when medical instruments are being oper-
Figure 2-8 Apple iChat AV user interface.