Hi All,
Sorry to be away for time. I've pulled together some code to do a
hilbert transform (from the university of york site) which i'll include
below in case anyone will find it usefull. If put a sample trought the
transform and then again will you get an invrerted signal i.e.
180degree shift. This code doesn't seem to do that si I'd be interested
in comments
cheers
#define NZEROS 500
#define GAIN 1.571116176e+00
static float xv_left[NZEROS+1];
static float xcoeffs[] =
{ +0.0000000000, +0.0003214310, +0.0000000000, +0.0003252099,
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-0.0000000000, -0.0003252099, -0.0000000000, -0.0003214310,
-0.0000000000,
};
float shiftLeft(float isamp)
{
float sum; int i;
for (i = 0; i < NZEROS; i++) xv_left[i] = xv_left[i+1];
xv_left[NZEROS] = isamp / GAIN;
sum = 0.0;
for (i = 0; i <= NZEROS; i++)
sum += (xcoeffs[i] * xv_left[i]);
return sum;
}
Just put a sample in as a parameter and you shoud get a shifted value
out as the result. The code has compiled under Visual C on windows.
Clay wrote:
> ingresman wrote:
> > Thanks guys I'll track down that book.
> >
> > As for the encoding Wendy Carlos has a great deal of info on her site.
> > You might remember switched on Back. The link is
> > http://www.wendycarlos.com/surround/surround4.html#matrix
>
> I remember back when "Switched on Bach" was released. It was by Walter
> Carlos.
>
> It seems that more than music may be synthesized ;-)
>
> Clay