Video Input

The most common source of a video input for a video conference is a camera, however it is possible to use other devices. Supplemental devices are designed to compliment a main camera, and offer specialist features.

It is important to remember that cameras "flatten" scenes they send. This change from 3D to 2D needs to be considered when arranging people and objects in the video conferencing room. [Graphic]

The two main categories of camera are:

  • Web Cam
    • Small, portable cameras are the most common kind of video conferencing camera.
    • These are relatively cheap and offer low-quality conferences for a very small number of participants.
    • The lens tends to be fixed rather than offering zoom or remote control functions.
    • Web Cams usually only work through a PC.
  • Room Systems
    • These are larger units, perhaps the size of a video recorder.
    • Room systems normally plug directly into the network and video output devices rather than requiring a PC.
    • The lenses on these units often zoom and move. This may be done by remote control.

Supplemental devices that might be used include:

  • Document Cameras
    • Document cameras are fixed cameras that, as their name suggests, are designed to show papers or small objects.
    • These tend to offer reasonable quality pictures, but are expensive, specialist equipment.
    • Quality is likely to be lower than a good quality scan or digital image file so where possible material should be distributed to remote sites in advance of the conference. Link
  • Secondary Cameras
    • A dedicated video conferencing suite might have more than one "normal" camera.
    • Using a secondary camera allows flexibility, for example, in having one camera on a lecturer, then another pointing at the audience reflecting the lecturer's viewpoint. This makes Q&A elements of a conference simpler.
  • PC
    • A PC screen can be used as a video source.
    • This enables presentation slides or Internet examples to be shared.
    • The quality of a PC signal delivered over a video conference is normally low, and much higher quality can be delivered using an alternative screen/application sharing method.
  • Video Recorder
    • A video recorder can provide the source image for a video conference.
    • Quality is likely to be reduced so where possible video material should be distributed to remote sites in advance of the conference. Link
  • DV Camera
    • Consumer Digital Video cameras can be used as the input of some systems.
    • These offer portability, good picture quality and many have excellent zoom capabilities.
    • However interoperability and support for clients is limited.