VoIP Mailing List Archives

[seandarcy2 at gmail.com]

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



--
_____________________________________________________________________
-- Bandwidth and Colocation Provided by http://www.api-digital.com --
New to Asterisk? Join us for a live introductory webinar every Thurs:
http://www.asterisk.org/hello

asterisk-users mailing list
To UNSUBSCRIBE or update options visit:
http://lists.digium.com/mailman/listinfo/asterisk-users