I have a cheap USB headset which records audio with the little
DC-Offset and noise at 50Hz.
As I know it's very usual problem of cheap audio devices and
integrated audio cards.
So I'm requesting a module which will filter input stream.
This pseudo code was suggested in alsa ML:
> xs=0
> while (input){
> xs=.01 xinput +.99 xs
> xoutput=xinput-xs
> }
> (This averages over roughly the last 100 inputs and subtracts the
> offset). If you want a longer averaging, change the coefficients.
Will be nice to have such module with sampling period as attribute.
