T=intpitch(ss,ipmax,ipmin)

function T=intpitch(ss,ipmax,ipmin)
%     
% :     - ss(1:360) 
% :  
%  : 
%   ss    -   
%   ipmax -     
%   ipmin -     
%  : 
%   T     -     

r=0;        %     
T=80;       %     
r_new=0;    %      ()
for tao=ipmin:ipmax     %   
    k=fix(tao/2);
    c0_t=ss(100-k:259-k)*ss(100-k+tao:259-k+tao)';  %  
    c0_0=ss(100-k:259-k)*ss(100-k:259-k)'; 
    ct_t=ss(100-k+tao:259-k+tao)*ss(100-k+tao:259-k+tao)'; 
    den=c0_0*ct_t;                                  %  
    if den>0 
        r_new=c0_t*c0_t/den;  %  
    end
    if r_new>r
        r=r_new;    %    
        T=tao;      %    
    end 
end