Re: Creating noise in the frequency domain?

Pixel.to.life wrote:
....
Do you have a way to visualize the fourier transformed (real and
complex) images? Synthesizing a white-noise carrying 2D image, then
fourier transforming it, then visualizing it would already give you
some insight.

done:

WN_s -> GN_f
WN_f -> GN_s
GN_s -> GN_f
GN_f -> GN_s

(WN: white noise, GN: gaussian noise, s: spatial domain,
f: frequency domain)

To produce random numbers in the frequency domain should be a fast
way to get gaussian noise in the spatial domain(?).
But he could also produce gaussian noise direct in the spatial
domain, for example:
phi:=2*pi*random;
r:=sigma*sqrt(-2*log10(random));
result:= r*sin(phi);

Ok, it doesnt seems to be faster.

Jens


.

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