Explanation of noise removal requested
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Explanation of noise removal requested
I am looking for some help in understanding the three parameters that are used in the beta noise removal. Just randomly moving the slide controls, it is clear that this is a significant improvement but how do you logically set these parameters?
Re: Explanation of noise removal requested
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Re: Explanation of noise removal requested
Thanks for pointing that out but the "explanation" just basically says that you set it to the middle and play with it. There must be some explanation as to what these levels do and how you can logically approach the settings. Also I think there is a mistake when it says to place the sliders at the halfway point and then move it to the left to increase and to the right to decrease. Isn't it the other way around? If the extreme left reads zero, I would think that moving to the right increases the effect.
Re: Explanation of noise removal requested
The explanation about where the two new sliders go is correct in the wiki. Left is definitely more aggressive than Right.
You're right about the explanation, it leaves something to be desired. I'll try to explain it in more detail, but realize that this is just an educated guess on my part, I didn't write the code. If you email Dominic Mazzoni you'll hopefully get a more qualified response.
First off, the default settings of the two new controls are well placed for most signals.
The Frequency Smoothing control alters how much of the lower frequencies are removed. High frequencies are always dealt with, as this slider moves to the right, fewer of the low frequencies will be removed from the signal. You can preserve more of the bass of the original signal with this slider, if you find that it's being cut out too much. If this slider is all the way to the left, all the frequencies contained in the noise profile will be reduced equally.
The Attack/decay setting alters how quickly the noise removal responds to changes in the dynamics of the original signal. If there is a section of 'silence' in the original signal followed by a loud section, the noise removal algorithm will allow more noise through when the signal is loud. If the slider is all the way to the left, the algorithm will respond immediately and (to a careful listener) the noise floor will suddenly "jump" a bit. This can be jarring in some circumstances. As the slider moves to the right, it will respond more slowly and the noise will be less noticeable if there are big jumps in the dynamics. Moving this slider to the right is useful for staccato signals and speech (but moving it too far to the right will reduce the effectiveness of the noise removal because the algorithm might not turn on quickly enough). Keep it further to the left for things like sustained organ tones.
You're right about the explanation, it leaves something to be desired. I'll try to explain it in more detail, but realize that this is just an educated guess on my part, I didn't write the code. If you email Dominic Mazzoni you'll hopefully get a more qualified response.
First off, the default settings of the two new controls are well placed for most signals.
The Frequency Smoothing control alters how much of the lower frequencies are removed. High frequencies are always dealt with, as this slider moves to the right, fewer of the low frequencies will be removed from the signal. You can preserve more of the bass of the original signal with this slider, if you find that it's being cut out too much. If this slider is all the way to the left, all the frequencies contained in the noise profile will be reduced equally.
The Attack/decay setting alters how quickly the noise removal responds to changes in the dynamics of the original signal. If there is a section of 'silence' in the original signal followed by a loud section, the noise removal algorithm will allow more noise through when the signal is loud. If the slider is all the way to the left, the algorithm will respond immediately and (to a careful listener) the noise floor will suddenly "jump" a bit. This can be jarring in some circumstances. As the slider moves to the right, it will respond more slowly and the noise will be less noticeable if there are big jumps in the dynamics. Moving this slider to the right is useful for staccato signals and speech (but moving it too far to the right will reduce the effectiveness of the noise removal because the algorithm might not turn on quickly enough). Keep it further to the left for things like sustained organ tones.