In order to extract the RTP payload from a pcap file captured by wireshark, I'm using tshark with the command
tshark -nr stream.pcap -i wlan1 -R 'rtp && ip.dst==192.168.1.64' -T fields -e rtp.payload
this succeeded with the codecs g.729 and ilbc but with the codec g.723 it wasn't the case. I think that this problem is due to the fact that the field payload of the rtp protocol doesn't exist any more (when consulting the wireshark).
Any idea of how to extract the payload of the codec g.723?