tune/eq/eq_compute_response.m

function [m, ph, gd] = eq_compute_response(z, p, k, f, fs)

%%
% Copyright (c) 2016, Intel Corporation
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% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
% AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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% Author: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
%

switch nargin
        case 3
                b = z;  % 1st arg
                f = p;  % 2nd arg
                fs = k; % 3rd arg
                h = freqz(b, 1, f, fs);
                m = 20*log10(abs(h));
                ph = 180/pi*angle(h);

                if length(b) == 1
                        gd = zeros(1, length(f));
                else
			if exist('OCTAVE_VERSION', 'builtin')
				% grpdelay() has some issue so better to not show a plot
				gd = NaN * zeros(1, length(f));
			else
				gd = 1/fs*grpdelay(b, 1, f, fs);
			end
                end
        case 5
                [b, a] = zp2tf(z, p, k);
                h = freqz(b, a, f, fs);
                m = 20*log10(abs(h));
                ph = 180/pi*angle(h);

                if length(z) == 0 && length(p) == 0
                        gd = zeros(1, length(f));
                else
			if exist('OCTAVE_VERSION', 'builtin')
				% grpdelay() has some issue so better to not show a plot
				gd = NaN * zeros(1, length(f));
			else
				gd = 1/fs*grpdelay(b, a, f, fs);
			end
                end
        otherwise
                error('Incorrect input parameters');
end

end