hello. i spent a few hours searching on google on how to extract technical data statistics from an audio file but to no avail. i suppose this is something simple but no way to know how to do it if nobody shows you. i downloaded a few small and open-source apps along the way but got nothing out of them.
i need to extract db range and Hz range as text from a given audio file and whatever other technical data is available by computer analysis. i read that the db range might be considered as “track volume” which i suppose reads the overall maximum db of the audio file or its loudness. i want a tool to analyze the file without having to play it back. is this possible in audacity? if so, how?
When dealing with audio signals, the “amplitude” (how big the waveform is vertically), is usually measured in dB relative to “full scale” (sometimes written as “dBFS”). “Full Scale” is the height of an audio track (marked on the scale on the left end of the track as +1.0 to =1.0).
The easiest way to find the peak amplitude of some audio in an Audacity track, is:
- Select the audio that you want to measure (see: http://manual.audacityteam.org/man/audacity_selection.html)
- Open the “Amplify” effect from the Effect menu. By default, the Amplify effect will offer to amplify the selected audio up to 0 dBFS. That means that the “Amplification (dB)” figure is the amount below 0 dB that the selection reaches.
If “Amplification (dB)” says “6.3”, then the max peak level of the selection is “-6.3” (negative because this is “dB below full scale”).
Audacity has “Plot Spectrum” for analyzing the frequency content. See: http://manual.audacityteam.org/man/plot_spectrum.html
Audacity also has “Sample Data Export” for detailed analysis of short sections of audio: http://manual.audacityteam.org/man/sample_data_export.html
There are some additional (optional) analysis plug-ins here: http://wiki.audacityteam.org/wiki/Nyquist_Analyze_Plug-ins