[OpenSIPS-Users] codec manipulation feature

[Jeff Pyle]

Hi Bogdan,

I'm looking for the ability to selectively remove codec advertisements from
the SDP.  For example, if my customer sends a call to me for PSTN
termination he may advertise G711 and G729, with G711 preferred.  By looking
at the number of existing dialogs I may know that he's running low on
bandwidth, so I would like to suppress the G711 advertisement ultimately
causing a 200 OK from the carrier with G729.

Generically, in this application we're looking only to suppress G711 at
certain times.

I understand normally codec selection is done completely by the gateway
device.  However, my gateway devices aren't smart enough to take bandwidth
utilization into consideration when choosing which codecs to advertise.  I'm
hoping my proxy might be.  :)

Does that make sense?



- Jeff



On 1/29/09 5:04 AM, "Bogdan-Andrei Iancu" <bogdan at voice-system.ro> wrote:

> Hi Jeff,
> 
> right now there is only available some functionality to check the codecs
> (to see what codecs are advertised in the SDP)... What exactly are you
> looking for (like codec ops) ?
> 
> Regards,
> Bogdan
> 
> Jeff Pyle wrote:
>> Bogdan,
>> 
>> Some months back you mentioned an upcoming feature that would allow
>> Opensips to manipulate the codecs present in the SDP.  Just wondering
>> if there is anything available to test yet.  This feature, in
>> combination with dialog contexts, will be of great use to us to allow
>> us to take a guess at the bandwidth consumption for a particular
>> customer and force the use of a compressed codec if necessary.
>> 
>> 
>> Thanks,
>> Jeff
>