Yes, as explained by alex the ptime depend on the frame size... The frame size for g.711 is 5ms, for g.729 is 10ms and for g.723 it is 30 ms. So the ptime for 711 and 729 can be 10, 20, 30... and for 723 it can be 30,60....
-Aneesh On Mon, Sep 22, 2008 at 1:50 PM, Alex Balashov <[EMAIL PROTECTED]>wrote: > There are no drafts or recommendations mandating that ptime be a > particular value because the desired packetisation duration is closely > related to the frame size and other characteristics of particular codecs. > > However, almost no media gateway equipment out there will support > anything other than the usual 10-30 ms for the usual suspects - > G.711u/A, G.729A, etc. > > There are certain recommendations or mandates for ptime values based on > particular codecs. For instance, 20 ms is recommended when using Speex > (http://www.speex.org/docs/manual/speex-manual/node14.html): > > --- > > 4.1.1. Registration of media type audio/speex > > Media type name: audio > > Media subtype name: speex > > Required parameters: > > None > > Optional parameters: > > ptime: see RFC 4566. SHOULD be a multiple of 20 msec. > > maxptime: see RFC 4566. SHOULD be a multiple of 20 msec. > > > > Sachin Rastogi wrote: > > > Hi All, > > Is there any rfc/draft or recommendation which suggests that 'ptime' > > value should multiple of 5 or 10? Can I use 'ptime' value as 11 or 12 or > 18 > > or 19? > > > > > > > > Thanks > > Sachin Rastogi > > _______________________________________________ > > Sip-implementors mailing list > > [email protected] > > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > > > -- > Alex Balashov > Evariste Systems > Web : http://www.evaristesys.com/ > Tel : (+1) (678) 954-0670 > Direct : (+1) (678) 954-0671 > Mobile : (+1) (706) 338-8599 > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > -- Aneesh _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
