This tool allows to record ogg formatted opus file for given RTP pcap.

Examples

Record opusfile from pcap containing RTP-stream

In one step using pcap_to_opus.py

TODO

In two step using tshark and hex_to_opus.py.

In case we have a in.pcap that contains the ethernet frames and UDP and RTP encapsulation, we can record audio like the following.

tshark -x -r in.pcap -Y "udp.srcport == myport" | cut -d " " -f 1-20 > tmp.txt
hex_to_opus.py -x tmp.txt --recordfile out.opus --rtpoffset 42

And if the pcap contains ethernet layer and UDP header, then rtpoffset(=42) should contain the length of those headers.

For encrypted packets, we can specify the srtpkey.

hex_to_opus.py -x tmp.txt --recordfile out.opus --rtpoffset 42 --srtpkey somebase64key

It is also possible to filter using ssrc and payload type.

hex_to_opus.py -x tmp.txt --recordfile out.opus --rtpoffset 42 --srtpkey somebase64key --ssrc 1234 --payloadtype 111

Requirements

- Python 3 (TODO make a python2.7 version)
- pylibsrtp (pip install pylibsrtp)

Gstreamer plugin for video

A gstreamer based video recorder is added as well.

tshark -x -r in.pcap -Y "udp.srcport == myport" | cut -d " " -f 1-20 > tmp.txt
hex_to_h264_gst_rfc3984.py -r output.mp4 -x tmp.txt --rtpoffset 42 -k "srtpkey"

Links

- similar tools for amr [Codec payload Extractor](https://github.com/Spinlogic/AMR-WB_extractor)
- [pylibsrtp](https://pylibsrtp.readthedocs.io/en/latest/)
- [srtp-decrypt](https://github.com/gteissier/srtp-decrypt)
- [opus-tools](https://opus-codec.org/downloads/)