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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am using rtpengine to proxy audio to/from media servers.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The outbound calls are being rejected by a couple of my carriers (although accepted by others), and the closest that I have been able to find for the reason is the inclusion of “a=rtcp:xxxxx” in the SDP generated by rtpengine.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>To test further, I am trying to remove this line. Rtpengine itself doesn’t have any options to remove it, so I am left with manipulating the generated SDP in Kamailio.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>A sample of generated SDP is:<o:p></o:p></p><p class=MsoNormal>a=maxptime:150<o:p></o:p></p><p class=MsoNormal>a=rtpmap:0 PCMU/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:8 PCMA/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:18 G729/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:101 telephone-event/8000<o:p></o:p></p><p class=MsoNormal>a=fmtp:18 annexb=no<o:p></o:p></p><p class=MsoNormal>a=fmtp:101 0-16<o:p></o:p></p><p class=MsoNormal>a=sendrecv<o:p></o:p></p><p class=MsoNormal>a=rtcp:30939<o:p></o:p></p><p class=MsoNormal>s=My Media Server<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am using <o:p></o:p></p><p class=MsoNormal>rtpengine_manage("RTP/AVP ICE=remove");<o:p></o:p></p><p class=MsoNormal>to generate the SDP to a variable ($avp(sdp))<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Now, I am trying to just remove the whole a=rtcp line with re.subst<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>$avp(sdp)=$(avp(sdp){re.subst,|a=rtcp:[0-9]*\R||s}); *** Tried / as delimiter also, but | looks cleaner ***<o:p></o:p></p><p class=MsoNormal>This should match the line and any CR/LF characters – BUT in results, nothing is changed (various online Regex testers show this match to be correct – I tried \r\n also).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>If I do the same but without the \R, then the line is removed but not the CR/LF, leaving a gap in the SDP – which is invalid.<o:p></o:p></p><p class=MsoNormal>$avp(sdp)=$(avp(sdp){re.subst,|a=rtcp:[0-9]*||s});<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Gives:<o:p></o:p></p><p class=MsoNormal>a=maxptime:150<o:p></o:p></p><p class=MsoNormal>a=rtpmap:0 PCMU/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:8 PCMA/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:18 G729/8000<o:p></o:p></p><p class=MsoNormal>a=rtpmap:101 telephone-event/8000<o:p></o:p></p><p class=MsoNormal>a=fmtp:18 annexb=no<o:p></o:p></p><p class=MsoNormal>a=fmtp:101 0-16<o:p></o:p></p><p class=MsoNormal>a=sendrecv<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>s=My Media Server<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Can anyone see where I am going wrong, or suggest an alternative?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='mso-fareast-language:EN-GB'>Kind Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-GB'>Mark Hall<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>