>>m=audio 9292 RTP/AVP 9 >>a=rtpmap:9 G722/48000 >>a=rtpmap:9 G722/56000 >>a=rtpmap:9 G722/64000
I'm not sure this would always work as desired. I think the effect will be that a receiver of this SDP will just end up selecting the last one in the list. Also, I think the rates are incorrect. The number after the '/' is the clock rate (or sample rate), not the bit rate. For example: a=rtpmap:0 PCMU/8000 is 8000 samples per second but 64kbits/second The 2nd version could work but you'd have to open multiple ports. The problem is that SDP wasn't really designed for capability negotiation. These problems are trying to be resolved here: http://tools.ietf.org/html/draft-ietf-mmusic-sdp-capability-negotiation-06 Regards, Attila -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Somesh S Shanbhag Sent: 06 August 2007 16:17 To: lalit kumar; Sip-implementors@lists.cs.columbia.edu Subject: Re: [Sip-implementors] few queries regarding SDP implementation formultiple bit rates for g.722 codec (Query 1) I think you can specify multiple a= lines in SDP m=audio 9292 RTP/AVP 9 a=rtpmap:9 G722/48000 a=rtpmap:9 G722/56000 a=rtpmap:9 G722/64000 (Query 2) m=audio 9292 RTP/AVP 9 0 a=rtpmap:9 G722/64000 a=rtpmap:0 PCMU/8000 m=audio 9296 RTP/AVP 9 18 a=rtpmap:9 G722/56000 a=rtpmap:18 G729/8000 m=audio 9298 RTP/AVP 9 a=rtpmap:9 G722/48000 (Query 3) Honestly dont know which one is better in network. Somesh lalit kumar <[EMAIL PROTECTED]> wrote: Help needed regarding G.722 codec negotiation. I have few queries regarding SDP implementation for multiple bit rates for g.722 codec. As we know that g.722 supports 48,56 and 64 kbps. Query-1: à I want to negotiate g.722 codec with multiple bitrates 64 56,and 48. Then what would be SDP attributes value in Sip invite. Query-2à if I have following codec order for negotiation, then what would be the SDP for Sip Invite? G.722 at 64 kbps PCMU G.722 at 56 kbps G.729 G.722 at 48 Kbps Query-3 à On network what flavor of G.722 codec is better at bit rates (64,56 or 48 kbps)? Please help me out, Thanks in advance. Thanks, Lalit -- Thanks & Regards Lalit Kumar _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors ----------------------------------------- SIMPLICITY IS THE BEAUTY. BE NATURAL LIVE NATURAL. ----------------------------------------- --------------------------------- Take the Internet to Go: Yahoo!Go puts the Internet in your pocket: mail, news, photos & more. _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
