[SIPForum-discussion] Different types of G729 codec

[Paul Kyzivat]

Please see:

http://tools.ietf.org/html/draft-ietf-mmusic-sdp-g723-g729-04

which addresses some problems with this.

	Thanks,
	Paul

On 8/29/13 6:07 AM, Binan AL Halabi wrote:
> Hi Waqas,
>
> Briefly:
> G.729 is audio coding algorithm (high complexity algorithm). G.729 has
> two extensions G.729a and G.729b.
>
> G.729a is compatible extension of G.729. G.729a requires less
> computations, less complexity and less voice quality accordingly.
> Platforms that support G.729 should support G.729a. Some VOIP phones
> does not recognize G.729a as G.729. This can lead to fail in the call
> establishment.
>
> G.729b and G.729ab are  silence compression scheme for G.729 and G.729a
>
> -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> annexX indicates that Annex X is used. It takes yes or no value.  "yes"
> is implied if annex-X parameter is omitted. so G.729 annexa=yes <--> G.729a
> and G.729 without annexa parameter <---> G.729a
>
> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Regarding  SDP offer/answer negotiation, it is expected to have
> something similar to this example:
>
> Offer with G729 annexb=yes. answer with G729 annexb=no. Both sides
> proceed as if G729 is negotiated with annexb=no.
>
> Offer with G729 annexb=yes. answer with G729 and no annexb parameter..
> Both sides proceed as if G729 is negotiated with annexb=yes.
>
> and so on.
>
> These Offer/Answer negotiation considerations are done by Cisco systems
> and Nokia Siemens networks. They are going to be standard soon (December
> 2013).
>
> Regards.
> //Binan.
>
> ------------------------------------------------------------------------
> *Från:* Waqas Arshad <waqas.arshad000 at yahoo.com>
> *Till:* "discussion at sipforum.org" <discussion at sipforum.org>
> *Skickat:* onsdag, 28 augusti 2013 17:06
> *Ämne:* [SIPForum-discussion] Different types of G729 codec
>
> Hi,
>
> Can someone please tell me the difference between following codecs in
> detail and their compatibility with each other?
>
> g729
> g729a
> g729b
> g729ab
> g729 annexa=yes
> g729 annexa=no
> g729 annexb=yes
> g729 annexb=no
>
> I'll highly appreciate the responses.
>
> Regards
> Waqas
>
>
>
> _______________________________________________
> This is the SIP Forum discussion mailing list
> TO UNSUBSCRIBE, or edit your delivery options, please visit
> http://sipforum.org/mailman/listinfo/discussion
> Post to the list at discussion at sipforum.org <mailto:discussion at sipforum.org>
>
>
>
>
> _______________________________________________
> This is the SIP Forum discussion mailing list
> TO UNSUBSCRIBE, or edit your delivery options, please visit http://sipforum.org/mailman/listinfo/discussion
> Post to the list at discussion at sipforum.org
>