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VoIP RTP player waveform screen blank

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Occasionally when I want to play back/analyze voip rtp traffic, I end up with no waveforms. I have this happen on Windows, Linux, and OS X platforms.

Screenshot available at http://www.apple2pl.us/screenshot.png

Is there something that I'm not doing that I should be?

asked 27 May '13, 05:16

cracklincrotch's gravatar image

cracklincrotch
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accept rate: 0%

edited 27 May '13, 05:17


One Answer:

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As far as I know, wireshark RTP stream decoding is limited to G.711 (A-law or u-law). Are you sure the captures with a 'blank screen' are encoded with G.711?

Regards
Kurt

answered 27 May '13, 14:22

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%

All RTP packets are G.711 u-law. Hitting the player button plays the audio fine. Just no waveforms, marked wrong timestamps, dropped packets, etc.

I should add, this is not the first time I've had this issue. There is no pattern to it. But I've seen this happen from time to time since 2011.

(27 May '13, 14:23) cracklincrotch

I have this happen on Windows, Linux, and OS X platforms.
I've seen this happen from time to time since 2011.

sounds like a yet undiscovered (and hard to detect) bug.

(27 May '13, 23:22) Kurt Knochner ♦