MATLAB: Sequel of a Specified Region

fftimage processingMATLABroi

sorry ImageAnalyst…
Unfortunately I deleted a question answered by ImageAnalyst and accepted by Me.
ImageAnalyst after doing filtering for particular portion is it possible to apply Fourier transform for that portion only to extract frequencies.

Best Answer

Yes, of course. You should know however that since your "infinite" image is multiplied by a mask (whatever region zeros out and crops stuff out) your spectrum will be convolved with the FT of the mask shape. Recall that multiplication in the spatial domain corresponds to convolution in the spectral domain.
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