How to implement anti-aliasing in the frequency domain?

Question

I want to smooth the image in the frequency domain. when I use google to view any articles, he gave some matlab codes that I don't need. I could do FFT for the image, but I don’t know how to implement any smoothing methods (ILPF, BLPF, IHPF, BHPF) in the frequency domain. if you can provide any code samples for any of the above methods WITHOUT using any image processing libraries, this will be very useful, and C # is preferred.

Thank,

Answer 1

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Answer 2

Code Code Christian Graus , , 2, , , :

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# GDI + 6 - HSL

Answer 3

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Answer 4

/ OpenCV.

#: Emgu.

http://www.emgu.com/wiki/index.php/Main_Page