Codecs

iLBC Freeware - iLBC (internet Low Bitrate Codec) is a FREE speech codec suitable for robust voice communication over IP. The codec is designed for narrow band speech and results in a payload bit rate of 13.33 kbit/s with an encoding frame length of 30 ms and 15.20 kbps with an encoding length of 20 ms. The iLBC codec enables graceful speech quality degradation in the case of lost frames, which occurs in connection with lost or delayed IP packets.

GIPS iLBC - GIPS iLBC a royalty free, low-bit rate codec with high packet loss robustness. iLBC delivers better speech quality than G.729A and G.723.1, under any conditions and offers substantially better quality when networks are congested and with the presence of packet loss. The iLBC codec is currently a work item of the IETF audio/video transport Working Group as a part of IETF’s standardization efforts.

SIPFoundry - Open-source SIP softphone that supports G.711

Internet Draft - Internet Low Bit Rate Codec

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