Automatic extraction of signals from many audio files
Automatic extraction of signals from many audio files
(OP)
Hi, this is my first post! I work as a water engineer but part of my job is product development.
So, I have a set of many audio files (1000+, will be larger when the project is commercial) which are around 2 minutes in length with around 10s of signal I care about and the rest is noise. I have a pretty good idea of what I’d like to do but not entirely sure of how to do it.
I'd like to take a FFT of the noise profile and subtract this from the waveform of the entire signal to attenuate the noise. Then extract the part of the file I'm interested in based off the differential in amplitude of the signal against the background noise. I'd then like to take this information and run an FFT on this part of the signal and normalise each of the different signals about a common peak frequency. Once this has been done I'd like to analyse add up the bins of the signal between 1kHz to 5kHz and output as a single number.
This is the initial stage of my project but I need to extract the signals before I can start playing with them :) Any help would be much appreciated!
Cheers
So, I have a set of many audio files (1000+, will be larger when the project is commercial) which are around 2 minutes in length with around 10s of signal I care about and the rest is noise. I have a pretty good idea of what I’d like to do but not entirely sure of how to do it.
I'd like to take a FFT of the noise profile and subtract this from the waveform of the entire signal to attenuate the noise. Then extract the part of the file I'm interested in based off the differential in amplitude of the signal against the background noise. I'd then like to take this information and run an FFT on this part of the signal and normalise each of the different signals about a common peak frequency. Once this has been done I'd like to analyse add up the bins of the signal between 1kHz to 5kHz and output as a single number.
This is the initial stage of my project but I need to extract the signals before I can start playing with them :) Any help would be much appreciated!
Cheers





RE: Automatic extraction of signals from many audio files
If the noise is 'white', then its spectrum will be flat. So you might not gain much by taking the FFT of it.
"...based off the differential in amplitude of the signal against the background noise."
In radio, that's called a squelch.
RE: Automatic extraction of signals from many audio files
Dan - Owner
http://www.Hi-TecDesigns.com
RE: Automatic extraction of signals from many audio files
RE: Automatic extraction of signals from many audio files
VE1BLL, the noise profile is not flat, it always tends to be a pink noise spectrum, but can vary between the different data sets. Hence why I want to take a sample of the noise and subtract the FFT of the noise spectrum from the entire signal.
RE: Automatic extraction of signals from many audio files
RE: Automatic extraction of signals from many audio files
Dan - Owner
http://www.Hi-TecDesigns.com
RE: Automatic extraction of signals from many audio files
Z
RE: Automatic extraction of signals from many audio files
Cheers
Greg Locock
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RE: Automatic extraction of signals from many audio files
Mike Halloran
Pembroke Pines, FL, USA
RE: Automatic extraction of signals from many audio files
TTFN
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RE: Automatic extraction of signals from many audio files