function F=extractGlobalColHist(img)

divs = 2;

dimensions = size(img);

width = dimensions(2);
height = dimensions(1);

pixel_count = width * height;

bin_values = zeros([1, pixel_count]);
count = 1;
for i = 1:length(img(:, 1, 1))
    for j = 1:length(img(1, :, 1))
        red = img(i, j, 1);
        green = img(i, j, 2);
        blue = img(i, j, 3);
        
        red_bin = floor(red*divs);
        green_bin = floor(green*divs);
        blue_bin = floor(blue*divs);
        
        bin_value = red_bin * (divs^2) + green_bin * (divs^1) + blue_bin;
        
        bin_values(count) = bin_value;
        
        count = count + 1;
    end
end

% hist_values = histogram(bin_values, (divs^3 - 1)).Values ./ pixel_count;
hist_values = histogram(bin_values, (divs^3 - 1), 'Normalization', 'probability').Values;

F=hist_values;
return;