function [ANdata,vFreq] = zilany2007humanized(stim_level,stim,fsstim,fsmod,varargin)
% ZILANY2007HUMANIZED Humanized auditory nerve model
% Usage: [ANdata,vFreq] = zilany2007humanized(lvl,stim,fsstim,fsmod);
%
% Input parameters:
% stim_level : Level of stimulus in peSPL
% stim : Pressure waveform of stimulus (timeseries)
% fsstim : Sampling frequency of stimulus
% fsmod : Model sampling frequency (often 200kHz)
%
% Output parameters:
% ANdata : AN exicitation in 500 different AN fibers spaced equally
% on the BM
% vFreq : Frequency vector containing the 500 center frequencies
%
% ZILANY2007HUMANIZED(stim_lvl, stim, fsstim, fsmod) returns simulations
% from Rønne et al. (2012). It calls the mex'ed C code containing the
% humanized version of Zilany et al. (2007)'s AN model. The humanization
% is described in Rønne et al. (2012). The AN model is called 500 times to
% simulate 500 fibers tuned to different center frequencies.
%
% Please cite Rønne et al (2012) and Zilany and Bruce (2007) if you use
% this model.
%
% This function takes the following optional parameters:
%
% 'flow',flow Lowest centre frequency. Default value is 100.
%
% 'fhigh',fhigh Highest centre frequency. Default value is 16000.
%
% 'nfibers',nf Number of fibers between lowest and highest
% frequency. The fibers will be equidistantly spaced
% on the basilar membrane. Default value is 500.
%
% Requirements and installation:
% 1) Compiled mex files (run amtmex)
%
% References:
% F. Roenne, J. Harte, C. Elberling, and T. Dau. Modeling auditory evoked
% brainstem responses to transient stimuli. J. Acoust. Soc. Am., accepted
% for publication, 2012.
%
% M. S. A. Zilany and I. C. Bruce. Representation of the vowel (epsilon)
% in normal and impaired auditory nerve fibers: Model predictions of
% responses in cats. J. Acoust. Soc. Am., 122(1):402-417, jul 2007.
%
%
% Url: http://amtoolbox.sourceforge.net/amt-0.9.6/doc/monaural/zilany2007humanized.php
% Copyright (C) 2009-2014 Peter L. Søndergaard and Piotr Majdak.
% This file is part of AMToolbox version 0.9.5
%
% 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/>.
if nargin<4
error('%s: Too few input parameters.',upper(mfilename));
end;
% Define input flags
definput.keyvals.flow = 100;
definput.keyvals.fhigh = 16000;
definput.keyvals.nfibers = 500;
[flags,kv] = ltfatarghelper({'flow','fhigh','nfibers'},definput,varargin);
stim = resample(stim,fsmod,fsstim); % stim fs = mod fs
idnz = stim ~= 0; % ignore pauses
lvlref = 20*log10(1/20e-6); % Reference level: 20 micro Pa
stim(idnz) = setdbspl(stim(idnz),stim_level,'dboffset',lvlref); % Calibrate level
% stim must be a row vector
if size(stim,2) == 1
stim = stim';
end
% location of lowest and highest centre frequency
xlo = (1.0/0.06)*log10((kv.flow/165.4)+0.88);
xhi = (1.0/0.06)*log10((kv.fhigh/165.4)+0.88);
% equal spaced distances on the BM
vX = linspace(xlo,xhi,kv.nfibers);
% and the resulting frequency vector
vFreq = 165.4*(10.^(0.06*vX)-0.88);
% resolution in the time domain
tdres = 1/fsmod;
% spontaneous rate in sp/sec
spont = 50;
% cohc is the ohc scaling factor: 1 is normal OHC function; 0 is complete
% OHC dysfunction
cohc = 1;
% cihc is the ihc scaling factor: 1 is normal IHC function; 0 is complete
% IHC dysfunction
cihc = 1;
% Call AN model - loop over the 500 fibers tuned to different CFs
for jj = 1:kv.nfibers
% Call AN model (mex'ed C model)
[timeout,meout,c1filterout,c2filterout,c1vihc,c2vihc,vihc,synout,psth500k] ...
= comp_zilany2007humanized(stim,...
vFreq(jj),...
1,...
tdres,...
length(stim)/fsmod,cohc, ...
cihc,...
spont);
% Use the output of the synapse stage of the AN model.
ANdata(jj,:) = synout;
end