function [m A eigenfaces pr_img] = eigenface_core(database_path)
  c = 1;
  d = 1;
  for i = 1:10
    path = strcat(database_path,'/');
    number = num2str(i);
    path = strcat(path, number);
    path = strcat(path,'.jpg');
    matrix = double(rgb2gray(imread(path)));
    [a b] = size(matrix);
    for k = 1:a
      for l = 1:b
        T(c,d) = matrix(k,l);
        c++;
      endfor
    endfor
    d++;
    c = 1;
  endfor
  [e f] = size(T);
  for i = 1:e
    m(i) = sum(T(i,:))/f;
    A(i,:) = T(i,:) - m(i);
  endfor
  AUX = A' * A;
  [B C] = eig(AUX);
  diagC = diag(C);
  g = size(diagC);
  h = 1;
  for i = 1:g
    if (diagC(i) > 1)
      V(:,h) = B(:,i);
      h++;
    endif
  endfor
  eigenfaces = A * V;
  pr_img = eigenfaces' * A;
endfunction