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Hi,all, I'm capturing telephony call packets between two endpoints. In my captured packets, there are RTP packets with payload type PT=PCMA, ISAC and CN(What is CN? what kind of codec?) I know how to save packets with PT=PCMA to .au files. However, when it comes to ISAC and CN, I have no idea how to convert them to .au or .wav files? Do you have any idea on this? Thank you!

asked 16 Nov '10, 16:26

esolve's gravatar image

accept rate: 0%

ISAC is a GIPS codec; see for details. CN is the "comfort noise" payload described in RFC 3389; as I understand it, it's used by several protocols.

I don't know of a save-to-au facility for the ISAC codec. Wireshark's save-to-au facility only works for the G.711 codec.

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answered 16 Nov '10, 17:29

wesmorgan1's gravatar image

accept rate: 4%

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question asked: 16 Nov '10, 16:26

question was seen: 6,381 times

last updated: 16 Nov '10, 17:29

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