“…In Fig. 7, curve 1 (method 1), curve 2 (method 2), and curve 3 (method 3) represent, respectively, coding based on the Q-decomposition [13], population coding [8], and population coding with comparison of masks [6,13]. Thus, the results of correlation comparison for PI network levels for different face images coded by method 3 (curve 3) do not correlate among themselves (the average correlation coefficient does not exceed 0.2).…”