iLBC (internet Low Bitrate Codec)

iLBC 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.

Features:

 * Bitrate 13.33 kbps (399 bits, packetized in 50 bytes) for the frame
   size of 30 ms and 15.2 kbps (303 bits, packetized in 38 bytes) for
   the frame size of 20 ms
 * Basic quality higher then G.729A, high robustness to packet loss
 * Computational complexity in a range of G.729A
 * Royalty Free Codec

WWW:	http://www.ilbcfreeware.org/