[Freeswitch-users] Opus codec in FreeSWITCH

[Jason White]

I have started testing the Opus 0.9.0 experimental codec in a recent
build of FreeSWITCH - thanks to Anthony Minessale for writing the
module, and thanks to William F. Acker for helping with the testing.

For those who aren't familiar with it, Opus is a combination of CELT and
SILK, which is currently under discussion within the IETF.

After building and loading the module, specify Opus-0.9.0 as your codec.
The versioning of the codec's name is a good idea; this should prevent
mutually incompatible versions from interacting with each other as
development of the codec proceeds.

My initial impressions are favourable; the audio quality is comparable
to CELT at 48 khz, based on my early listening experience.

I did notice some occasional pops in the audio, presumably attributable
to packet loss. SILK apparently has some error correction functionality
built in, but I don't know what its status is in the combined Opus
codec. If it's present, then it didn't smooth out the glitches, at least
in my environment.