From Wikipedia, the free encyclopedia
Internet Low Bitrate Codec (iLBC) is a royalty-free[1] narrowband speech codec, developed by Global IP Solutions (GIPS) formerly Global IP Sound. It is suitable for VoIP applications, streaming audio, archival and messaging. The algorithm is a version of block-independent linear predictive coding, with the choice of data frame lengths of 20 and 30 milliseconds. The encoded blocks have to be encapsulated in a suitable protocol for transport, usually the Real-time Transport Protocol (RTP).
iLBC handles the case of lost frames through graceful speech quality degradation. Lost frames often occur in connection with lost or delayed IP packets. Ordinary low-bitrate codecs exploit dependencies between speech frames, which unfortunately results in error propagation when packets are lost or delayed. In contrast, iLBC-encoded speech frames are independent and so this problem will not occur.
iLBC is defined in RFC 3951. It is one of the codecs used by Gizmo5, Ekiga, QuteCom, Google Talk, Yahoo! Messenger, Polycom IP Phone and Maemo Recorder (on the Nokia N800/N810) and many others.
[edit] Parameters and features
[edit] See also
[edit] References
[edit] External links
