[OpenSIPS-Users] codec manipulation feature

[Jeff Pyle]

Hi Bogdan,

Just curious if you had a chance to see what the status is of this SDP
manipulation code.


Thanks,
Jeff



On 6/15/09 6:36 PM, "Bogdan-Andrei Iancu" <bogdan at voice-system.ro> wrote:

> Hi Jeff,
> 
> I have some code from last year - let me check it out and see what is
> the status.
> 
> Regards,
> Bogdan
> 
> Jeff Pyle wrote:
>> Hi Bogdan,
>> 
>> It¹s been a little while since we talked about this. I was wondering
>> if there was anything in the works to detect and/or manipulate the
>> codecs present in an SDP.
>> 
>> 
>> 
>> - Jeff
>> 
>> 
>> 
>> On 2/1/09 4:08 AM, "Steve Kurzeja" <steve.kurzeja at gmail.com> wrote:
>> 
>>     This idea is quite standard in SBCs, typically called codec
>>     profiles, where you permit only certain codecs to be passed
>>     through the SBC in an INVITE and all the rest are stripped out.
>> 
>>     We use it to get around interop issues with certain codecs. E.g.
>>     we have some end devices/customers that have issues using g729a so
>>     we choose to remove this codec for these specific endpoints.
>> 
>>     The poor man's method to implementing this is just doing header
>>     manipulations in the SDP but it would be nice to be standardized.
>> 
>>     Regards,
>>     Steve
>> 
>> 
>>     On Fri, Jan 30, 2009 at 2:20 AM, Jeff Pyle
>>     <jpyle at fidelityvoice.com> wrote:
>> 
>>         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
>>>