Videoconferencing at UVa
A personal computer is typically identified as either a Macintosh (Apple) or a PC (Microsoft operating system). When investigating desktop collaboration software, it quickly becomes apparent that the PC, and in particular the Windows operating system, is the platform of choice among software developers. The Macintosh has excellent potential as a video conferencing platform since the audio capabilities, and often the video capabilities, are included in the basic configuration of modern models. However, the software companies that are developing products for videoconferencing are targeting the business market. Macintosh computers are relatively rare in business settings, while Windows machines are very common. True standards-based videoconferencing software for the Macintosh is practically non-existent.
The system requirements that software companies typically list for their products should be regarded as the minimum configuration that will allow the software to function at a basic level. This is especially true for the requirements that are stated for desktop video conferencing applications. In general, the PC must have Windows, a decent processor, and sufficient memory, but most recent computers fulfill these requirements.
This basic configuration allows one to run the video conferencing application by itself (no other programs active) at an acceptable frame rate. However, desktop systems are not usually devoted to a single application. Most users will have several other programs active, such as a word processor, a web browser, a spreadsheet, a calendar, etc. Each active application must share resources with the other active applications. Also, the value of desktop collaboration is enhanced by the associated applications (such as a whiteboard), which also require computing resources. In order to make full use of a desktop collaboration program as part of a normal work routine, the computer must have much more than a minimum configuration.
Commercial desktop collaboration packages usually bundle the software, (perhaps) a board to be installed in the PC, a camera, and speakers and a microphone, or a headset. The board is primarily a CODEC (compression/decompression), which processes the video signal in hardware. Systems that do not have a CODEC board depend upon software compression and decompression, which both affects and is affected by the speed of the computer processor. The board may also have sound circuitry on it, which not only makes a separate sound card unnecessary, but also will allow the video conferencing program to synchronize the audio and video signals. This is especially important when there is a noticeable time lag between transmission and reception. Some videoconference peripherals incorporate the CODEC into the unit that houses the camera, making an added board not necessary. Finally, some videoconference appliances do not require a computer at all, having all necessary functionality built into the unit. These, however, have little (or no) ability to host true data collaboration software.
Shareware and freeware programs such as NetMeeting depend on the addition of audio and video hardware to a system. It is the responsibility of the computer owner to acquire the separate elements that will work with the application, work in the computer, and work together. This task may prove to be difficult not because of wrong choices, but because there are so many choices that can be made. Audio and video equipment is available in a broad range of price categories. A multimedia system that is already capable of recording and reproducing sound will need only the addition of a camera (which will use the computer's processor for software compression) or a video capture card (hardware compression) . Anyone who has ever added memory or a peripheral card to a PC is capable of adding this type of audio and video hardware for desktop collaboration systems.
Page Updated: 2012-02-16