tomwalters@0: 
bleeck@3: % This external file is included as part of the 'aim-mat' distribution package
bleeck@3: % (c) 2011, University of Southampton
bleeck@3: % Maintained by Stefan Bleeck (bleeck@gmail.com)
bleeck@3: % download of current version is on the soundsoftware site: 
bleeck@3: % http://code.soundsoftware.ac.uk/projects/aimmat
bleeck@3: % documentation and everything is on http://www.acousticscale.org
bleeck@3: 
tomwalters@0: %
tomwalters@0: 
tomwalters@0: function nvals=leakyintegrator(sig,lowpass_cutoff_frequency,order)
tomwalters@0: 
tomwalters@0: 
tomwalters@0: time_constant=1/(2.*pi.*lowpass_cutoff_frequency);
tomwalters@0: sr=getsr(sig);
tomwalters@0: vals=getvalues(sig);
tomwalters@0: b=exp(-1/(sr.*time_constant));
tomwalters@0: gain=1./(1-b);
tomwalters@0: 
tomwalters@0: 
tomwalters@0: nvals=zeros(size(vals));
tomwalters@0: for dothis=1:order
tomwalters@0: 	xn_1=0;
tomwalters@0: 	yn_1=0;
tomwalters@0:     for i=1:length(vals)
tomwalters@0:         xn=vals(i);
tomwalters@0:         yn= xn + b*yn_1 ;
tomwalters@0:         xn_1=xn;
tomwalters@0:         yn_1=yn;
tomwalters@0:         nvals(i)=yn;
tomwalters@0:     end
tomwalters@0:     vals=nvals./gain;
tomwalters@0: end
tomwalters@0: 
tomwalters@0: nvals=vals;