The widespread use of digital processing technology has found its way into a variety of equipment and, in some form, into most industries. In many applications involving communication of different types of information, data processing arrangements have been configured to multiplex information from each type of information source over various communication-media types and arrangements.
Video communication applications of this technology have become increasingly popular. Videoconferencing, for example, is becoming more common in both business and residential applications. Videoconferencing permits audio as well as visual live communication between two remotely located terminals communicating over a single channel. Videoconferencing has had limited success due to, for example, unavailability of a common network interface, overly complex controls, poor video quality, limited functionality, inconvenience, and high cost. Improving video quality and functionality while simultaneously decreasing costs has proven to be a seemingly unobtainable goal. For this reason, there have been opposing pressures to develop certain other systems that forego the convenience and quality criteria for the sake of reducing costs.
In some videoconferencing applications, it is desirable to make use of additional functions to supplement audio and video capabilities. For example, in certain applications involving multiple participants at one or more of the terminals, dedicating a videocamera to each participant facilitates better viewing of each participant. Similarly, dedicating a microphone to each participant makes each participant easier to hear. In certain applications, it is desirable to print paper copies of transmitted images. Peripheral devices that can be used to provide these additional functions use a wide variety of input or output ports and communication protocols. Furthermore, the devices are accessed using a variety of types of software. Attempting to implement such a variety of ports, protocols, and software has been difficult and expensive. Moreover, additional ports tend to increase the physical size of the base unit.
One recent approach that attempts to address some of the above-mentioned issues uses a digital videocamera coupled to an input port of a PC that is programmed to provide videoconferencing over a communications channel, such as the Internet. Peripheral devices, such as additional videocameras, microphones, and printers, can be installed on respective ports of the PC. This approach is useful for applications where a PC is readily available and the user is fully familiar with downloading the software and using the PC to control the videoconferencing. However, the approach is disadvantageous for environments directed to those who are not as computer literate or not interested in using a computer for videoconferencing. In addition, PC's typically have a limited number of available ports, thus limiting the number of peripheral devices that can be connected.