How to use masking filter to remove particular frequency from an image?

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I have modified the code of ImageAnalyst for one the tasks that I am currently working on. Goal is to extract the QR code from the image. Previously I extracted the QR code by using a notch filter but it is highly sensitive to distortion and doesnt work as soon as image is no more in-plane.
Attached is the code based on masked filter (originally written by Image Analyst) and the image I am working on. But once I have removed the frequencies, it it gives me a noisy output like salt and pepper noise.
Looking forward to constructive feedback on the query.
  4 Comments
waqas
waqas on 21 Oct 2018
No QR code is simply added as a layer on the pattern so the noise right now goes beyond the set noise correction factor of 25% in QR code which makes it unreadable. Idea about removing the bright spikes in the frequency domain is to treat these white and black dots as periodic noise and then get rid of them.
Previous discussion on the similar topic with Image Analyst is in the following link: (he did not reply there so I started new thread here)
https://se.mathworks.com/matlabcentral/answers/418501-how-to-find-specific-frequency-from-image
Ideally when we adjust the contrast in imtool then we should be able to read the QR code.

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