After you captured the audio stream using Wireshark, you want to playback the RTP stream. Unfortunately, Wireshark can only decode G711 streams but the stream that you captured is G729. Follow the steps below to playback G729 streams
1- Open the capture in Wireshark,
2- If you do not see the RTP packets (G729) , you might need to select the UDP packets -> right click and select Decode As… -> RTP (in the scrolling menu)
3- The rtp packets should now show up as G729.
4- Go to “Statistics -> RTP -> Show All Streams”. Select the desired stream and press “Analyze”.
5- Select “Save Payload…”. Save options are Format = .raw and Channel = forward. Name file sample.raw. The file should now be saved on your PC in RAW format.
6- Convert the .raw file to .pcm format using the Open G.729 decoder.
Syntax: va_g729_decoder.exe sample.raw sample.pcm.raw
Or for Linux: wine va_g729_decoder.exe sample.raw sample.pcm.raw
7- Open Audacity and select “Project -> Import Raw File…”.
8- Select the sample.pcm.raw file and choose
- Signed 16-bit pc
- No endianness
- 1 channel (mono)
- Start offset: 0
- Amount to import: 100%
- Sample rate: 8000
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This really works & wonderful to see results.
Art,
This is good stuff, thanks.
Thanx so much, we were looking for this for a long time
Really Cool Article….
Thanks So much…
Funciona muy bien, gracias.
Works fine, thank you.
Thanks so much for the instruction on importing the pcm file into audacity. Finally get this work after trying so long.
Tnx!
I’ve been trying for long time and it worked perfectly!
Thanks! This was incredibly helpful.
It worked perfectly, Thank you!