Audacity Forum

Hello,

I would check the sound level of a VOIP communication. For this I catch a VOIP communication using wireshark. And I extract voice packets (RTP Sinus 1000 Hz). I get a. Raw. The communication uses the G711 codec A-law.
Then I import this file with audacity.
Encoding: A-Law
Sampling frequency: 8000 Hz
Byte order: little endian mode / big endian (no difference)
Channels 1 Channel Mono
Start Offset 0
...

Well then I get the desired signal (1000 Hz).

Following this test I have some questions:
1) What is the amplitude displayed on the vertical bar on the left?
2) What is the relationship between the amplitude displayed on audacity and the level indicated in the standard G711 (ex max 3.14dbm0 for the law-a).
3) Is this when we import a. Raw effects are applied to it (compression / ...)?
4) In which case the byte order is used (endian)?

Thank you in advance

My configuration Windows XP version 1.3.9

I don't know much about voip, so just your first question...

Audio samples have values in the range of +/- 1
A wave that touches both extremes (+1 to -1) is "full scale" 0dB
A wave that goes +0.5 to -0.5 is -6dB

If you click on the track name there is a drop down menu where you can select a dB scale - note that in this view the waveform will look weird because the dB values are equally spaced. You can also grab the lower edge of a track and drag it down to increase the vertical size of the track.