[OpenSIPS-Users] Route selection based on SDP codecs

[John Quick]

If a call is has G.729 set as the preferred codec in the SDP, I want to send it to an Asterisk server
with transcoding capabilities. If the preferred codec is G.711 I will send it directly to the media
server, gateway or other destination.

I can use TEXTOPS to search for entries like this in the SDP:
m=audio 10004 RTP/AVP 18
a=rtpmap:18 G729/8000

(a) Is there a better way than using regular expression searches of the message body?
(b) How certain is it that G.729 will always use 18 to identify it in the SDP?

Many thanks.

John Quick
Systems Consultant
Smartvox Limited