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Lets say I have a program like Skype and I call to my friend. I want to create a test to figure out what is the average delay from the audio, from my mic to his speakers.

I want to measure:

  • delay in one instance of time
  • delay over longer period (60 s)

Assumptions that i can make:

  • at least 8000 samples per second.
  • devices are in the same room and network propagation delay is negligible.
  • external mic and photo-detector/camera should be used.
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I recently ecountered this problem too (about a month ago). This is what I found..

Network delay measuring protocol (NDMP) - little useful free-ware program. I used the same program to measure other VoIP call delay.

You can download it from here: ReadMe file is included in .zip file.

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Oh niice, i was just looking for that. Opened it and works fine! Will use it tomorrow and give feedback. – user3213 Nov 1 '12 at 17:03

We may use audio recording software like adobe audition for this purpose.

  • We can use the stereo mix feature of windows to record the mic input and speaker output.

  • Start the recording software at both ends, and record some portion of your communication.

  • Now compare some prominent portion like sudden jump in audio within this software. You will get approximate delay between these audio files.

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