AMR-WB transcoding

[Sergey Zyrianov]

Hi,

When transcoding AMR-WB to PCMA the shape of RTP stream with PCMA payload follows AMR side during silence intervals. Which gives 160ms delay between consecutive RTP packets with PCMA payload. That degrades audio quality on some PCMA receivers.

Question is if there are config options to make PCMA side to tick with 20ms packets regardless of what AMR side is doing ? 

Here is example of transcoded AMR-WB on PCMA side, top row's delay is not running according to a=ptime:20 :

Following config was used  in this case:--dtx-delay 20 --max-dtx 0 --silence-detect 0.05 

Version: 10.5

Thanks.

[Richard Fuchs]

This version should already do that with the config you provided. Double check that the settings are actually active and not overridden by a config file or something.

Cheers

[Sergey Zyrianov]

according to ps: 

rtpengine -d 0 -E --foreground --listen-ng=<ip:port> --listen-http=<ip:port> --log-level=4 --port-min=30000 --port-max=40000 -i internal/ip1 -i external/ip1 -t -1 --dtx-delay 20 --max-dtx 0 --silence-detect 0.05 --homer=homer

May be should change to use "=" --dtx-delay=20 ? or --config-file=none ?

Thanks

[Sergey Zyrianov]

I see this, so should be good, the config: 

[dtx] Using DTX ptime 20 based on handler=20 codec=20