%%
%% *SpHEAR Project
%%
%% sphear_fir_design: design a matrix of FIR filters that equalizes the microphone
%%
%% usage:
%%   [FIR] = sphear_fir_design(F, A2BF, n, Fs)
%%
%% F: array of filter section center frequencies
%% A2BF: vector of A2B matrixes
%% n: order of the FIR filter being created
%% Fs: sampling rate
%%
%% Copyright 2016, Fernando Lopez-Lezcano, All Rights Reserved
%% nando@ccrma.stanford.edu
%%
%%  This program is free software: you can redistribute it and/or modify
%%  it under the terms of the GNU General Public License as published by
%%  the Free Software Foundation, either version 3 of the License, or
%%  (at your option) any later version.
%%
%%  This program is distributed in the hope that it will be useful,
%%  but WITHOUT ANY WARRANTY; without even the implied warranty of
%%  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%%  GNU General Public License for more details.
%%
%%  You should have received a copy of the GNU General Public License
%%  along with this program.  If not, see <http://www.gnu.org/licenses/>.

function [FIR] = sphear_fir_design(F, A2BF, n, Fs)

  FIR = zeros(4, 4, (n + 1));

  %% frequency range
  f = [0 F' Fs/2]' / (Fs/2);

  %% all b format components
  for b = 1:4
    %% all capsules
    for c = 1:4
      r = [ A2BF(1,c,b) A2BF(:,c,b)' A2BF(end,c,b)]';
      FIR(b, c, :) = fir2(n, f, r);
    end
  end
  
end