Information on Video Codecs

X-lite has various video codecs implemented. The implemented codecs of the X-lite 3.0 version are H.263 and H.263+. For example YouTube and Google Video also use this encoding format. The improvement of H.263 has lead to the development of H.263v2 (or H.263+) in 1998 and H.263v3 (or H.263++) in 2000. A significant improvement has lead to the development of H.264 and is also known as MPEG-4 (part 10). This H.264 codec is not available when using X-lite, but is available when using eyebeam 1.5, although some codecs require payment of royalities for their use in a product or program.

Codec	Compression method	Transfer rate
H.263	Videocodec (DCT)	16-256 Kbps
G.261	Videocodec (DCT)	64-256 Kbps

Whether the H.263 codec uses 16 or 256 Kbps or anything in between is (still) unclear to me.

H.263 is a codec designed for videoconferencing using low-bitrate compression. With H.263 the contraints on the bit rate are applied externally and are given by the used terminal or the network.