function y = pitchShiftViaTSM(x,n,parameter)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Name: pitchShiftViaTSM
% Date: 03-2014
% Programmer: Jonathan Driedger
% http://www.audiolabs-erlangen.de/resources/MIR/TSMtoolbox/
%
% Pitch modification via time-scale modification. The input signal is first
% stretched and resampled afterwards to achieve the pitch modification
% effect.
%
% Input:    x               input signal.
%           n               amount of pitch shifting that should be applied
%                           to the signal given in cents. Positive numbers
%                           indicate an upwards pitch shift, negative
%                           numbers a downwards pitch shift.
%           parameter.
%               fsAudio     the sampling rate of the input audio signal x.
%               algTSM      handle to the time-scale modification algorithm
%                           that should be used to stretch the signal prior
%                           to the resampling.
%
% Output:   y               the pitch modified output signal.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Reference: 
% If you use the 'TSM toolbox' please refer to:
% [DM14] Jonathan Driedger, Meinard Mueller
%        TSM Toolbox: MATLAB Implementations of Time-Scale Modification 
%        Algorithms
%        Proceedings of the 17th International Conference on Digital Audio  
%        Effects, Erlangen, Germany, 2014.
%
% License:
% This file is part of 'TSM toolbox'.
% 
% 'TSM toolbox' is free software: you can redistribute it and/or modify it
% under the terms of the GNU General Public License as published by the
% the Free Software Foundation, either version 3 of the License, or (at
% your option) any later version.
% 
% 'TSM toolbox' 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 'TSM toolbox'. If not, see http://www.gnu.org/licenses/.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% check parameters
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if nargin < 3
    parameter = [];
end

if ~isfield(parameter,'fsAudio')
    parameter.fsAudio = 22050;
end
if ~isfield(parameter,'algTSM')
    parameter.algTSM = @hpTSM;
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% some pre calculations
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
fsAudio = parameter.fsAudio;
algTSM = parameter.algTSM;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% pitch modification
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
alpha = nthroot(2,12)^(n/100);
yTsm = algTSM(x,alpha);
[p,q] = rat(fsAudio/round(alpha * fsAudio),0.0001);
y = resample(yTsm,p,q,8);

y = normalizeLength(y,size(x,1));
end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% normalizeLength
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function y = normalizeLength(x,len)
if size(x,1) < len
    padLen = len - length(x);
    y = [x;zeros(padLen,size(x,2))];
else
    y = x(1:len,:);
end

end