FT2Dc.m

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% 2d centered Fourier transform
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% Citation for this code and algorithm:
% Tatiana Latychevskaia and Hans-Werner Fink
% "Practical algorithms for simulation and reconstruction of digital in-line holograms",
% Appl. Optics 54, 2424 - 2434 (2015)
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% The code is written by Tatiana Latychevskaia, 2002
% The version of Matlab for this code is R2010b

function [out] = FT2Dc(in)

[Nx,Ny] = size(in);

f1 = zeros(Nx,Ny);

for ii = 1:Nx
    for jj = 1:Ny
         f1(ii,jj) = exp(1i*pi*(ii + jj));
    end
end

FT = fft2(f1.*in);

out = f1.*FT;
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