C

	Camera presets
	Allows pre-defined camera angles to be programmed into a videoconferencing system.
	CCITT (Consultative Committee for international Telegraphy and Telephony)
	The world’s leading telecommunications standards organization responsible for establishing interoperability standards for communications systems.
	CIF (Common Intermediate Format)
	An international standard for video display formats developed by TSS. The QCIF format, which employs half the CIF spatial resolution in both horizontal and vertical directions, is the mandatory H.261 format. QCIF is used for most desktop videoconferencing applications where head and shoulder pictures are sent from desk to desk.
	CODEC (Coder Decoder)
	In the videoconferencing world, a video codec converts analogue video signals from a video camera to digital signals for transmission over digital circuits, and then converts the digital signals back to analogue signals for display.
	Compressed Video
	When the vast amount of information in a normal TV transmission is squeezed into a fraction of its former bandwidth by a codec, the resulting compressed video can be transmitted more economically over a smaller carrier. Some information is sacrificed in the process, which may result in diminished picture and sound quality. An uncompressed NTSC signal requires about 90 Mbps of throughput, greatly exceeding the speed of all but the fastest and shortest of today's networks. Squeezing the video information can be accomplished by reducing the quality (sending fewer frames in a second or displaying the information in a smaller window) or by eliminating redundancy.
	Compression
	Compression is a technique that reduces the quantity of bandwidth or bits required to encode a block of information so that it occupies less space on a transmission channel or storage device and a fundamental concept of video communications.