% GDFTRealTest.m
%
% demonstrates the use of GDFTRealCmplx() and GDFTRealCmplx()
% in combination with ModifyPrototype() and MakeTDL().
%
% S Weiss, Univ. of Southampton, 21/1/2001

% prototype filter and parameters
p = filter16_14_448;
K = 16; N = 14; Lp = 448;
p_mod = ModifyPrototype(p,K);

% real valued input signal
Lx = 2*Lp;
x = randn(1,Lx);

% initialisation of output TDL for GDFTSynCmplx() 
y_tdl = zeros(1,Lp);

% iteration for analysis and synthesis operations
for k = 1:N:Lx,
   U = MakeTDL(x,k,Lp);											% extract TDL
   X = GDFTAnaReal(U,K,p_mod);								% analysis
   [y(k:k+N-1) y_tdl] = GDFTSynReal(X,N,p_mod,y_tdl);	% synthesis
end;  

% display of I/O to cascaded analysis and synthesis filter bank
clf; 
plot(x(1:end-Lp+1)); hold on; plot(y(Lp:end),'r:'); hold off;
legend('FiBa input','delayed FiBa output');
ylabel('input, output'); title('I/O for real valued GDFT OSFB');
xlabel('time [fullband sampling periods]');