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% Task: Creating FFT of average R,G,B over a period of 30 seconds
%
% Input: 
%	- CSV file containing the RGB data for each pixels of the region of interest
%
% Output:
%	- Fast Fourier Transform of the colors over time
%
% author: Delattre Loïc, Dey Maryne (loic.delattre@ecam.fr, maryne.dey@ecam.fr)
% date: 06/02/2023
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pkg load io %% to be able to extract from external format (excel)

data = csvread('RGB_database/RGB_data.csv');
standard_deviation = std(data);
mean_value = mean(data);

for i = 1:size(data,1)
  normalized_data_G(i,1) = (data(i,2)-mean_value(2))/standard_deviation(2); %%2 and not 1 because green is the 2nd color
endfor

normalized_data_G

fft_green = fft(normalized_data_G);

frequency = [];

for i = 1:length(fft_green)
  frequency(i) = (i-1)*30/length(fft_green);
endfor

plot(frequency,fft_green)


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%For all the colors
%%for j = 1:3
%%  for i = 1:size(data,1)
%%    normalized_data(i,j) = (data(i,j)-mean_value(j))/standard_deviation(j);
%%  endfor
%%endfor
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