function [tfr,rtfr,hat] = tfrrsp(x,t,N,h,trace);%TFRRSP Reassigned Spectrogram.%	[TFR,RTFR,HAT] = TFRRSP(X,T,N,H,TRACE) %	computes the spectrogram and its reassigned version.% %	X     : analysed signal.%	T     : the time instant(s)      (default : 1:length(X)).%	N     : number of frequency bins (default : length(X)).%	H     : frequency smoothing window, H(0) being forced to 1%	                                 (default : Hamming(N/4)).%	TRACE : if nonzero, the progression of the algorithm is shown%	                                 (default : 0).%	TFR,  : time-frequency representation and its reassigned%	RTFR    version. When called without output arguments, %	        TFRRSP runs TFRQVIEW.%	HAT   : Complex matrix of the reassignment vectors.%%	Example :%	 sig=fmlin(128,0.1,0.4); t=1:2:128;%	 h=window(17,'Kaiser'); tfrrsp(sig,t,64,h,1);%%	See also  all the time-frequency representations listed in%	 the file CONTENTS (TFR*)%	F. Auger, May-July 1994, July 1995.%	Copyright (c) 1996 by CNRS (France).%%	------------------- CONFIDENTIAL PROGRAM -------------------- %	This program can not be used without the authorization of its%	author(s). For any comment or bug report, please send e-mail to %	f.auger@ieee.org if (nargin == 0), error('At least 1 parameter required');end;[xrow,xcol] = size(x);if (nargin <= 2), N=xrow;end;hlength=floor(N/4);hlength=hlength+1-rem(hlength,2);if (nargin == 1), t=1:xrow; h = window(hlength); trace=0;elseif (nargin == 2)|(nargin == 3), h = window(hlength); trace=0;elseif (nargin == 4), trace = 0;end;if (N<0), error('N must be greater than zero');end;[trow,tcol] = size(t);if (xcol~=1), error('X must have only one column');elseif (trow~=1), error('T must only have one row'); elseif (2^nextpow2(N)~=N), fprintf('For a faster computation, N should be a power of two\n');end; [hrow,hcol]=size(h); Lh=(hrow-1)/2; if (hcol~=1)|(rem(hrow,2)==0), error('H must be a smoothing window with odd length');end;if (tcol==1), Dt=1; else Deltat=t(2:tcol)-t(1:tcol-1);  Mini=min(Deltat); Maxi=max(Deltat); if (Mini~=Maxi),  error('The time instants must be regularly sampled.'); else  Dt=Mini; end; clear Deltat Mini Maxi;end;tfr= zeros(N,tcol); tf2= zeros(N,tcol); tf3= zeros (N,tcol);if trace, disp('Spectrogram'); end;Th=h.*[-Lh:Lh]'; Dh=dwindow(h);for icol=1:tcol, ti= t(icol);  tau=-min([round(N/2)-1,Lh,ti-1]):min([round(N/2)-1,Lh,xrow-ti]); indices= rem(N+tau,N)+1; if trace, disprog(icol,tcol,10); end; norm_h=norm(h(Lh+1+tau)); tfr(indices,icol)=x(ti+tau).*conj( h(Lh+1+tau)) /norm_h; tf2(indices,icol)=x(ti+tau).*conj(Th(Lh+1+tau)) /norm_h; tf3(indices,icol)=x(ti+tau).*conj(Dh(Lh+1+tau)) /norm_h;end ;tfr=fft(tfr);% tf2=round(real(fft(tf2)./tfr/Dt));% tf3=round(imag(N*fft(tf3)./tfr/(2.0*pi)));tf2=fft(tf2);tf3=fft(tf3);avoid_warn=find(tfr~=0);tf2(avoid_warn)=round(real(  tf2(avoid_warn)./tfr(avoid_warn)/Dt));tf3(avoid_warn)=round(imag(N*tf3(avoid_warn)./tfr(avoid_warn)/(2.0*pi)));tfr=abs(tfr).^2;if trace, fprintf ('\nreassignment: \n'); end;rtfr= zeros(N,tcol); Ex=mean(abs(x(min(t):max(t))).^2); Threshold=1.0e-6*Ex;for icol=1:tcol, if trace, disprog(icol,tcol,10); end; for jcol=1:N,  if abs(tfr(jcol,icol))>Threshold,   icolhat= icol + tf2(jcol,icol);   icolhat=min(max(icolhat,1),tcol);   jcolhat= jcol - tf3(jcol,icol);   jcolhat=rem(rem(jcolhat-1,N)+N,N)+1;   rtfr(jcolhat,icolhat)=rtfr(jcolhat,icolhat) + tfr(jcol,icol) ;   tf2(jcol,icol)=jcolhat + j * icolhat;  else   tf2(jcol,icol)=inf*(1+j);   rtfr(jcol,icol)=rtfr(jcol,icol) + tfr(jcol,icol) ;  end; end;end;if trace, fprintf('\n'); end;clear tf3;if (nargout==0), continue=1; while (continue==1),  choice=menu ('Choose the representation:',...               'stop',...               'spectrogram',...               'reassigned spectrogram');  if (choice==1), continue=0;  elseif (choice==2),    tfrqview(tfr,x,t,'tfrsp',h);  elseif (choice==3),   tfrqview(rtfr,x,t,'tfrrsp',h);  end; end;elseif (nargout>2), hat=tf2;end;