linuxaudio.org

On Wed, Dec 01, 2010 at 05:21:09PM +0300, Andrew Gaydenko wrote:
> On Wednesday, December 01, 2010 16:33:35 fons@kokkinizita.net wrote:

quoted text
> > > I'm afraid direct amplitude caculation in accorance with a0...aN will

> > > produce "too fast" signal deviation, resulting in exceeding fs/2 band.

> >

> > Any non-linear transfer function will do this for some inputs.

> > If you have an x^N term, anything above Fs/(2*N) will alias.

> > If you want the nonlinearity without aliasing, you have to

> > upsample (by a factor N, with N = highest power of x used),

> > apply the nonlinear function, then downsample.

>

> Fons, thanks! It is *that* trick I needed to eliminate my doubts wrt fs/2

> products :-) I think SRC is an approriate lib for up/down-sampling.

For the fixed ratios you need zita-resampler will probably

somewhat faster.
--

FA
There are three of them, and Alleline.
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