function y=voicebox(f,v)
%VOICEBOX  set global parameters for Voicebox functions Y=(FIELD,VAL)
%
%  Inputs:  F   is a field name
%           V   is a new value for the field
%
% Outputs:  Y   is set equal to the structure of parameters if the
%               f and v inputs are both present or both absent. If only
%               input f is specified, then y is set to the value of the
%               corresponding field or null if it doesn't exist.
%
% This routine contains default values for constants that are used by
% other functions in the VOICEBOX toolbox. Values in the first section below,
% entitled "System-dependent directory paths" should be set as follows:
%    PP.dir_temp     directory for storing temporary files
%    PP.dir_data     default directory to preappend to speech data file names 
%                    when the "d" option is specified in READWAV etc.
%    PP.shorten      location of SHORTEN executable. SHORTEN is a proprietary file compression
%                    algorithm that is used for some SPHERE-format files. READSPH
%                    will try to call an external decoder if it is asked to
%                    read such a compressed file.
%    PP.sfsbin       location of Speech Filing Sysytem binaries. If the "c" option
%                    is given to READSFS, it will try to create a requested item
%                    if it is not present in the SFS file. This parameter tells it
%                    where to find the SFS executables.
%    PP.sfssuffix    suffix for Speech Filing Sysytem binaries. READSFS uses this paremeter
%                    to create the name of an SFS executable (see PP.sfsbin above).
% Other values defined in this routine are the defaults for specific algorithm constants.
% If you want to change these, please refer to the individual routines for a fuller description.

%      Copyright (C) Mike Brookes 2003
%      Version: $Id: voicebox.m,v 1.7 2005/06/07 08:34:43 dmb Exp $
%
%   VOICEBOX is a MATLAB toolbox for speech processing.
%   Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%   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 2 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 can obtain a copy of the GNU General Public License from
%   ftp://prep.ai.mit.edu/pub/gnu/COPYING-2.0 or by writing to
%   Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

persistent PP
if isempty(PP)
    
    % System-dependent directory paths
    
    PP.dir_temp='F:\TEMP';                      % directory for storing temporary files
    PP.dir_data='F:\data\speech';               % default directory to preappend to speech data file names 
    PP.shorten='C:\bin\shorten.exe';            % location of shorten executable
    PP.sfsbin='F:\Program Files\SFS\Program';   % location of Speech Filing Sysytem binaries
    PP.sfssuffix='.exe';                        % suffix for Speech Filing Sysytem binaries
    
    % RAPT pitch tracker
    
    PP.rapt_f0min=50;           % Min F0 (Hz)
    PP.rapt_f0max=500;          % Max F0 (Hz)
    PP.rapt_tframe=0.01;        % frame size (s)
    PP.rapt_tlpw=0.005;         % low pass filter window size (s)
    PP.rapt_tcorw=0.0075;       % correlation window size (s)
    PP.rapt_candtr=0.3;         % minimum peak in NCCF
    PP.rapt_lagwt=0.3;          % linear lag taper factor
    PP.rapt_freqwt=0.02;        % cost factor for F0 change
    PP.rapt_vtranc=0.005;       % fixed voice-state transition cost
    PP.rapt_vtrac=0.5;          % delta amplitude modulated transition cost
    PP.rapt_vtrsc=0.5;          % delta spectrum modulated transition cost
    PP.rapt_vobias=0.0;         % bias to encourage voiced hypotheses
    PP.rapt_doublec=0.35;       % cost of exact doubling or halving
    PP.rapt_absnoise=0;         % absolute rms noise level
    PP.rapt_relnoise=2;         % rms noise level relative to noise floor
    PP.rapt_signoise=0.001;     % ratio of peak signal rms to noise floor (0.001 = 60dB)
    PP.rapt_ncands=20;          % max hypotheses at each frame
    PP.rapt_trms=0.03;                      % window length for rms measurement
    PP.rapt_dtrms=0.02;                     % window spacing for rms measurement
    PP.rapt_preemph=-7000;                  % s-plane position of preemphasis zero
    PP.rapt_nfullag=7;                      % number of full lags to try (must be odd)
    
    
end
if nargin==0
    if nargout==0
        % list all fields
        nn=sort(fieldnames(PP));
        cnn=char(nn);
        fprintf('%d Voicebox parameters:\n',length(nn));
        
        for i=1:length(nn);
            fprintf('  %s = %s\n',cnn(i,:),PP.(nn{i}));
        end
    else
        y=PP;
    end
elseif nargin==1
    if isfield(PP,f)
        y=PP.(f);
    else
        y=[];
    end
else
    if isfield(PP,f)
        PP.(f)=v;
        y=PP;
    else
        error(sprintf('''%s'' is not a valid voicebox field name',f));
    end
end