blurring function

function [b_time, b_freq] = blurring_function(M_t, M_f, hop, N, win_t, win_f)
%
% M_f: long window size
% M_t: short window size
% hop: hop size
% N : fftsize
% win_t : short window
% win_f : long window

win_t = [win_t; zeros(M_f-M_t,1)];

% time-domain blurring function
R_t = (M_f-M_t)/hop + 1;

big_win_t = zeros(M_f,R_t);
for i=1:R_t
    big_win_t(:,i)= circshift(win_t,hop*(i-1));
end

b_time = big_win_t\win_f;
%b_time = b_time/sum(b_time);

% frequency-domain blurring function
R_f = ceil(N/M_t*8 + 1);

if ( mod(R_f,2) == 0 )
    R_f = R_f + 1;
end

zpf = 1;
win_t_fft = fftshift(abs(fft(win_t,N*zpf)));
win_f_fft = fftshift(abs(fft(win_f,N*zpf)));

big_win_f_fft = zeros(N*zpf,R_f);
for i=1:R_f
    big_win_f_fft(:,i)= circshift(win_f_fft,(-(R_f-1)/2-1+i)*zpf);
end

b_freq = big_win_f_fft\win_t_fft;
%b_freq = b_freq/sum(b_freq);