I am having problems in understanding how to do it practically
I have a wav file that contains pure speech and another ave file that just contains the background noise (can be various things, such as white noise, crowd noise, a recording of blowing wind, etc). These are either purely speech or purely noise. So I suppose I can get an SNR value from them by simple division of corresponding samples (or the average of a frame of samples) in both files. I then combine them in audacity to get a noisy speech file. I am guessing this file will still have the same SNR.
Now I pass this file through my noise reduction program and get another file as a result. How do I calculate the SNR of this "noise reduced" file?
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follow-up question posted HERE