How to compute power spectrum from 2D FFT

Posted by user1452954 on Stack Overflow See other posts from Stack Overflow or by user1452954
Published on 2013-11-08T19:42:01Z Indexed on 2013/11/08 21:53 UTC
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fft

I've encounter a problem when doing my lab assignment, not sure how to implement this:

Use fft2 on a gray image and to do Fourier transform and then compute the power spectrum. This is my code so far:

>> Pc = imread('pckint.jpg');
>> whos Pc;
  Name        Size             Bytes  Class    Attributes

  Pc        256x256            65536  uint8              

>> imshow(Pc);
>> result = fft2(Pc);

My question is from the result. How to computer power spectrum?

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