Summary:ASTERISK-20701: Siren14 does not translate from/to slin32
Reporter:Mathis Schmieder (mathis)Labels:
Date Opened:2012-11-19 09:17:16.000-0600Date Closed:
Versions:Frequency of
Environment:Ubuntu 12.04 x86_64 running Linux 3.2.0 and Asterisk 11.0.1 stable releaseAttachments:
Description:The closed source siren14 codec offers no translator from and to slin32, only slin16 and slin. In order to sample the 14kHz bandwidth of siren14, a sample rate of at least 28kHz is needed. If it is wanted to record a siren14 channel in a raw audio format, a translator between siren14 and slin32 is needed.
As there is no openly available en/decoder for the siren14 codec for the Linux OS, the possibility to record in another superwideband codec like slin32 would be highly useful, especially in cases where the full bandwidth of siren14 is needed.
Comments:By: Alexander Traud (traud) 2017-11-27 03:39:36.165-0600

Are you still facing this issue?

Asterisk 11 LTS is [not supported| http://wiki.asterisk.org/wiki/display/AST/Asterisk+Versions] since October 2017. Therefore, I tried Asterisk 13 LTS for which Digium added a Polycom Siren module in August 2016 (see ASTERISK-26021). With that version/module, I was not able to reproduce your issue. In my case, siren14 is transcoded via slin32, which I double-checked via the command-line interface (CLI): {{core show channels}}. If I transcode to another format with 32 kHz like speex32, Asterisk does not resample and transcodes via slin32.

However, if Asterisk has to transcode to a format with a lower sample rate, the quality is not wide-band but just narrow-band (slin8) because of ASTERISK-23735. If I go for the patch for that issue, siren14 transcodes to slin32 and then resamples to slin16 as expected.

Nevertheless, I could have done something different. Therefore, do you still face that issue? If you cannot update to Asterisk 13 LTS, please, try again with your Asterisk 11. Your What does {{core show channels}} state?