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image processing - Circle detection using invariance kernels


I'm not sure, if this belongs more to the signal processing forum or if I can post it in here, but I want to solve it via mathematica and it's some kind of image-processing I guess.



I have a noisy picture with a circle in it:


enter image description here


Now I want to detect the circle, by using so called invariance Kernels like a Fourier-Mellin transform. In short, I want to replicate what the authors of this paper (see Section 4) did in mathematica. So what they did, was using Fourier-Mellin transform to detect a noisy image with a circle in it. I have some troubles grasping the mathematics behind it and I hope someone could help me out in understanding and implementing it in a mathematica code.




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