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by jbay808 1269 days ago
It's so classical, it can be done without a digital computer at all, using fourier optics! The true fastest fourier transform, done at the speed of light.

https://en.wikipedia.org/wiki/Fourier_optics

At the focal plane of a lens, an image is converted into its spatial fourier components. By adding blocking elements at that focal plane (eg. an aperture, or a piece of glass with marker dots), unwanted frequency components can be cut out from the image.

1 comments

Aha - very nice!

My background with Fourier optics is mostly theoretical and the applications numerical.

Any references (books or online) exist about physical applications, like the one you mention?