Hi, The RTP payload type that PJSIP uses for the G726-32 codec is 2. See the PJMEDIA_RTP_PT_G726_32 constant in pjmedia/include/pjmedia/codec.h. However, RFC 3551, page 31 states the following (see http://www.ietf.org/rfc/rfc3551.txt): "Payload type 2 was assigned to G721 in RFC 1890 and to its equivalent successor G726-32 in draft versions of this specification, but its use is now deprecated and that static payload type is marked reserved due to conflicting use for the payload formats G726-32 and AAL2-G726-32 (see Section 4.5.4)." Table 4 in the RFC confirms this: PT encoding media type clock rate channels name (Hz) ___________________________________________________ ... 2 reserved A ... dyn G726-32 A 8,000 1 RFC 3551 is also referred to in the comments in pjmedia/include/pjmedia/codec.h. Attached patch fixes this by making PJMEDIA_RTP_PT_G726_32 a dynamic payload type (in pjmedia/include/pjmedia-codes/types.h). Without this fix, the SDP negotiation appears to never select the G726-32 codec if the remote party mentions it as a dynamic payload type (which is the case for both voip providers I tested this with). Regards, Bram -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: G726-32_RTP_payload_type_patch.diff URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20100417/834d2b64/attachment.diff>
