wolffd@0: function varargout = mirbrightness(x,varargin)
wolffd@0: %   b = mirbrightness(s) calculates the spectral brightness, i.e. the amount
wolffd@0: %       of spectral energy corresponding to frequencies higher than a given
wolffd@0: %       cut-off threshold.
wolffd@0: %   Optional arguments:
wolffd@0: %   b = mirbrightness(s,'CutOff',f) specifies the frequency cut-off 
wolffd@0: %       threshold in Hz.
wolffd@0: %           Default value: f = 1500 Hz.
wolffd@0: %
wolffd@0: % Typical values for the frequency cut-off threshold:
wolffd@0: %       3000 Hz in Juslin 2000, p. 1802.
wolffd@0: %       1000 Hz and 500 Hz in Laukka, Juslin and Bresin 2005.
wolffd@0: %
wolffd@0: %   Juslin, P. N. (2000). Cue utilization in communication of emotion in 
wolffd@0: % music performance: relating performance to perception. Journal of 
wolffd@0: % Experimental Psychology: Human Perception and Performance, 26(6), 1797?813.
wolffd@0: %   Laukka, P., Juslin, P. N., and Bresin, R. (2005). A dimensional approach 
wolffd@0: % to vocal expression of emotion. Cognition and Emotion, 19, 633?653.
wolffd@0: 
wolffd@0: 
wolffd@0:         cutoff.key = 'CutOff';
wolffd@0:         cutoff.type = 'Integer';
wolffd@0:         cutoff.default = 1500;
wolffd@0:     option.cutoff = cutoff;
wolffd@0:     
wolffd@0: specif.option = option;
wolffd@0: specif.defaultframelength = .05;
wolffd@0: specif.defaultframehop = .5;
wolffd@0: 
wolffd@0: 
wolffd@0: varargout = mirfunction(@mirbrightness,x,varargin,nargout,specif,@init,@main);
wolffd@0: 
wolffd@0: 
wolffd@0: function [x type] = init(x,option)
wolffd@0: if not(isamir(x,'mirspectrum'))
wolffd@0:     x = mirspectrum(x);
wolffd@0: end
wolffd@0: type = 'mirscalar';
wolffd@0: 
wolffd@0: 
wolffd@0: function b = main(s,option,postoption)
wolffd@0: if iscell(s)
wolffd@0:     s = s{1};
wolffd@0: end
wolffd@0: m = get(s,'Magnitude');
wolffd@0: f = get(s,'Frequency');
wolffd@0: w = warning('query','MATLAB:divideByZero');
wolffd@0: warning('off','MATLAB:divideByZero');
wolffd@0: v = mircompute(@algo,m,f,option.cutoff);
wolffd@0: warning(w.state,'MATLAB:divideByZero');
wolffd@0: b = mirscalar(s,'Data',v,'Title','Brightness');
wolffd@0: 
wolffd@0: 
wolffd@0: function v = algo(m,f,k)
wolffd@0: if not(any(max(f)>k))
wolffd@0:     warning('WARNING in MIRBRIGHTNESS: Frequency range of the spectrum too low for the estimation of brightness.');
wolffd@0: end
wolffd@0: sm = sum(m);
wolffd@0: v = sum(m(f(:,1,1) > k,:,:)) ./ sm;