%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
%
% 2 Dimensional Fourier Transform
%
%       [imafft,mag,phi] = fft2d(ima_in)
%
% This function calculates the complex Fourier transform
% and the associated magnitude and phase (mag, phi) of the input real
% image ima_in. 
%
%       ima_in : real input image
%       imafft : output complex image
%                real and imaginary part can be accessed through real
%                and imag function (see help real, imag)
%
%       mag,phi: magnitude and phase of the fourier transform
%
% Yvan Petillot, December 2000                                  
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function [imafft,mag,phi] = fft2d(ima_in)
  
  imafft = fftshift(fft2(fftshift(ima_in)));
  mag = abs(imafft);
  phi = angle(imafft);
  %Display results
  clf;       %Clear display
  figure(1); %Create figure
  subplot(1,3,1);  %Separate figure in 3 and selects 1st partition
  imagesc(ima_in); % Scale image to [0 255] range and siplay it
  xlabel('Original Image');
  axis square;     % Display equal on x and y axes
  colormap(gray);  % Sets gray scale colormap;
  subplot(1,3,2);  % Selects the second partition
  imagesc(log(mag+1));    % Display magnitude
  xlabel('Log Magnitude of the spectrum');
  axis square;     % Display equal on x and y axes
  subplot(1,3,3);  % Selects the second partition
  imagesc(phi);    % Display phase
  axis square;     % Display equal on x and y axes
  
  drawnow;         % Ready to dipslay: Do it