sean darcy
2016-Apr-28 12:30 UTC
[asterisk-users] codec_opus w/ PLR and FEC for Asterisk 11
There is an opus patch for asterisk 11. https://github.com/seanbright/asterisk-opus/tree/asterisk-11 . But it doesn't have Packet Loss Resilience or Forward Error Correction, both of which are important for voip. 2.1.6. Packet Loss Resilience Audio codecs often exploit inter-frame correlations to reduce the bitrate at a cost in error propagation: after losing one packet, several packets need to be received before the decoder is able to accurately reconstruct the speech signal. The extent to which Opus exploits inter-frame dependencies can be adjusted on the fly to choose a trade-off between bitrate and amount of error propagation. 2.1.7. Forward Error Correction (FEC) Another mechanism providing robustness against packet loss is the in-band Forward Error Correction (FEC). Packets that are determined to contain perceptually important speech information, such as onsets or transients, are encoded again at a lower bitrate and this re-encoded information is added to a subsequent packet. There is an opus patch for asterisk 13 that includes PLR and FEC. https://github.com/traud/asterisk-opus. We don't have approval to move to 13. So anybody have an opus patch for 11 that includes PLR and FEC ? sean