MATLAB: How i remove repetitive structure like line or circle using notch filter in image

fftimage analysisimage processing

Hi,I am want to remove certain repetitive structure from image in Fourier domain FFT using some filter like notch filer. In our image circle or line is the repetitive structure how can I remove in FFT domain and later reconstruct again using IFFT. Please guide me and give simple code for notch filter. thanks

Best Answer

You can use a Fourier filter. See attached demo and adapt as needed.

Related Solutions

MATLAB: Ifft in 2D : wrong reasoning

True, narrow things in one domain mean wide things in the other. So delta functions in one domain mean infinitely wide things (lines, planes) in the other domain. Still, you need to think a little differently in 2D. A dot (spike, delta function) in 1D gives a single line in 1D spatial domain, and I think you understand that and why that is. However a dot in 2D Fourier domain is a plane in the 2D spatial domain. This would be so much easier to visualize if you had a degree in Optics (like I do) and played around for years in the laser lab, and can visualize the patterns as diffraction patterns - once you get an intuitive feel for thinking like that, it all becomes a lot clearer.

MATLAB: A help with fourier transform

Assuming your * means convolution, which is often two *, and knowing that convolution in one domain is multiplication in the other domain:

fft(sinc**sinc) = fft(sinc) * fft(sinc) = rect*rect = rect

and

ifft(rect) = sinc = same as what you started with.

so sinc**sinc = sinc.

Best Answer

Related Solutions

MATLAB: Ifft in 2D : wrong reasoning

MATLAB: A help with fourier transform

Related Question