[asterisk-users] codec_opus w/ PLR and FEC for Asterisk 11
seandarcy2 at gmail.com
Thu Apr 28 07:30:33 CDT 2016
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.
We don't have approval to move to 13. So anybody have an opus patch for
11 that includes PLR and FEC ?
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