How does Goldwave do filtering?

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Videogamer555
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Joined: Wed May 25, 2011 2:28 am

How does Goldwave do filtering?

Post by Videogamer555 »

In addition to the frequency domain filter, there's the high/low pass filter tool, and the band pass/stop filter tool. Given how fast they operate, I assume they are using an IIR filter rather than an FIR filter. However, in the research I've done on IIR filters, to compute the coefficients you need to use a Z transform (which is a very advanced mathematical concept) but nothing in the dialog boxes for these tools mentions any Z transform, so it appears you may have found an alternate way to computer the coefficients in the IIR filter.

Did you manage to break down the Z transform into a simple set of sines and cosines, sort of like with the discreet fourier transform, such that you only need to compute a few sines and cosines in order to get the coefficients of the IIR filter? If this isn't a trade secret, please let me know. Thanks in advance.
GoldWave Inc.
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Re: How does Goldwave do filtering?

Post by GoldWave Inc. »

GoldWave uses IIR filters. There are many books that give the equations for calculating the coefficients for certain kinds of filters (low pass, high pass, etc.).
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