Re: Creating noise in the frequency domain?

Matthias wrote:
WN_s -> GN_f
WN_f -> GN_s
GN_s -> GN_f
GN_f -> GN_s

Oh, really that straightforward?
Great, but can you specify what aspect of the complex numbers you are
talking about?

Real & imaginary parts

From what range do I have to pick values in the frequency domain to
get Gaussian noise in the spatial domain (does it matter)?

(Random-0.5)*3.4626 (just do it for all real&imag values) should bring
a standard deviation of 1, some more or less. I got this number by try.

Dont know how Matlab handles it, but the values should also be
downscaled by the size of the FT.

And do you have any links or references?

No sorry, ive done the conversion in my program and looked at the
deviation in the histogramm.

Jens


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