Filtered sound/event activated recording

[cazorla]

if could have a record to buffer mode
so not only can do more processing to determine whether to keep the audio data,
but also have option to not lose (user set amount) the previous second(s) of audio just before that
(no pre-trimming problem, with extra padding)

if the criteria for recording could be also not only for volume
but whether it is tonal, sounds-like-noise, is voice-like

and to possibility for adaptive threshold (changing noise floor-over time) e.g. traffic

[cazorla]

maybe add option to measure volume similar to

https://www.itu.int/dms_pubrec/itu-r/re ... !PDF-E.pdf

Subjective tests were conducted at five sites around the world to
create a subjective database for evaluating the performance
of potential loudness measurement algorithms.
Subjects matched the loudness of various monophonic audio sequences to a reference sequence.
The audio sequences were taken from actual broadcast material (television and radio).
In conjunction with these tests, a total of ten commercially developed monophonic loudness
meters/algorithms were submitted by seven different proponents for evaluation at the Audio
Perception Lab of the Communications Research Centre, Canada.

It can be seen that the data points are
tightly clustered around the diagonal, indicating the very good performance of …

Leq(RLB) meter was found to provide the best performance of all of the meters evaluated

a simple energy-based loudness measure is similarly robust compared to more complex
measures that may include detailed perceptual models

[steve]

maybe add option to measure volume similar to
https://www.itu.int/dms_pubrec/itu-r/re ... !PDF-E.pdf

That would not help with the use case that you described in your first post because the specification does not discriminate against very low (or very high) frequencies.
A better solution for your use case would be to filter out very low frequencies from the signal before it enters the computer, for example, by using a microphone that has a low-cut (bass roll-off) filter.