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Two-dimensional fast Fourier transform.
Syntax
Y = fft2(X) Y = fft2(X,m,n)
Description
Y = fft2(X)
performs a two-dimensional FFT, producing a result Y the same size as X. If X is a vector, Y has the same orientation as X.
Y = fft2(X,m,n)
truncates or zero pads X, if necessary, to create an m-by-n array before performing the FFT. The result Y is also m-by-n.
The fft2 function is part of the standard MATLAB language.
Algorithm
fft2(x) is simply
fft(fft(x).').'This computes the one-dimensional
fft of each column of x, then of each row of the result. The time required to compute fft2(x) depends on the number of prime factors in [m,n] = size(x). fft2 is fastest when m and n are powers of 2.
See Also
fft |
One-dimensional fast Fourier transform. |
fftshift |
Rearrange the outputs of fft and fft2. |
ifft |
One-dimensional inverse fast Fourier transform. |
ifft2 |
Two-dimensional inverse fast Fourier transform. |