Re: [WM]: Fourier Transform in matlab

[vfotop1@eap.gr]

Dear friend,

since you're working with images,you can use matlab's
fft2 function.

x=double(imread('The full filename of your image file')); X=fft2(x); Xm=abs(X); Xa=angle(X);

then Xm will be the magnitude and Xa the angle of x's fft transform. Keep in mind that if you want to see the well known spectrum
image that all image related books have (the one with the cross in the middle) then you better do fftshift before. That will
diagonally exchange the 4 quadrants of the spectrum.For example,try

imagesc(fftshift(Xm))

or for better observation

imagesc(fftshift(log(Xm)))

To get back the original image:

xrecon=ifft(Xm.*exp(i*Xa));

Kind regards
Vassilis Fotopoulos



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