[Freeswitch-users] trans-coding is not working

[Dahlberg, David]

Am Donnerstag, den 30.01.2014, 22:02 +0100 schrieb thomas peterseil:
> hello brian,
> thanks for your help! as far as i understood the default config of FS,
> it takes the codec list from the vars.xml file. i have both codecs
> (PCMU,PCMA) there:
> --------------
>   <X-PRE-PROCESS cmd="set" data="global_codec_prefs=G722,PCMU,PCMA,GSM"/>
>   <X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,PCMA,GSM"/>
> --------------

Right, but the default configuration (i.e. the "vanilla demo") also sets
"inbound-late-negotiation" and "zrtp-passthru", which implicitly sets
"inbound-late-negotiation". 

"Late negotiation" with "inherit codec" will make FS only to offer only
those codecs on the outbound side, that it received on the inbound
side. 

For example be there a setup "A -- FS -- B", A uses G.711A and G.711µ,
FS uses G.711A and GSM-FR, and B uses GSM-FR. If then FS receives an
"INVITE B, codec PCMA, PCMU" from A, it will forward PCMA as the only
codec choice to B.

See http://wiki.freeswitch.org/wiki/Codec_Negotiation

Regards,
	David






-- 
David Dahlberg     

Fraunhofer FKIE, Dept. Communication Systems (KOM) | Tel: +49-228-9435-845
Fraunhoferstr. 20, 53343 Wachtberg, Germany        | Fax: +49-228-856277