Is there a way with Audacity (or any other software) to find and and mark the 5 loudest and 5 softest points in a movie audio file? It seems like this should be easy to do.
I know next to nothing about audio software
I’m running OS X 10.10.1 and Audacity 2.0.6
I also have Win 8 and 10 VMs running
It seems trivial, but it isn’t.
Firstly, loudness isn’t measureable. There exist some loudness curves, based on numerous listening tests (e.g. Fletcher-Manson).
All filters that are based on this curves are not perfect, to say the least.
One can of course simply measure the power or energy of the wave form over a specific time span. This won’t give you information about the actual loudness (again, some kind of filter helps a bit).
Example:
Let’s say we have the samples 1 -1 1 -1 1 -1 1 -1
This gives an Rms value of 1 or 0dB.
At 48000 Hz sample rate, you won’t hear anything at all and at 2000 Hz, it will be loudest.
Let’s assume that we are happy with the pure Rms value and want to measure those 10 points like that.
You could for example use the sound and silence finders in the Analyze menu to find exactly 5 labels for each.
You will notice that you have to vary the duration of the audio event as well as the thresholds, which define a loud/quiet event.
I could write some nyquist plug-in that returns e.g. the 5 “loudest” passages but you must be aware that their are additional constraints needed like ignoring events under 0.1 s length.