www.pudn.com > CELP.ZIP > psearch.m

function psearch(sube1) 
 
global frames pdmin pdmax pcbsize pcode pgain TRUE FALSE 
global shiftrange szsubf sub_cnt bpb intp pdlyindx pdelay frange prev del_intv 
 
% For the first sub-frame, which is empty, just assume a pitch code 
if sub_cnt==1                            
    pcode(sub_cnt)=1; 
    prev=pcode(sub_cnt); 
    pgain(sub_cnt)=0.0; 
else 
 
    % Integer pitch delay search 
 
    % Move the intp+pdmin-1 behind of the pitch buffers ahead 
    pdelay(1:intp+pdmin-1)=bpb(szsubf+1:intp+szsubf+pdmin-1);        
     
        if rem(sub_cnt-1,del_intv)~=0                    % Full pitch search only on first sub-frame for each frame. 
            if (prev-shiftrange/2)<=1                    %    
                bkl=1;                                   % 
                bkh=bkl+shiftrange-1;                    % Find search range for delta search use 
            elseif (prev+shiftrange/2)>=pcbsize          % 
                bkh=pcbsize;                             % 
                bkl=bkh-shiftrange+1;                    % 
            else                                         % 
                bkl=prev-shiftrange/2;                   % 
                bkh=prev+shiftrange/2-1;                 % 
            end 
            % Routine searching integer pitch delay and gain 
            [pcodei,pgaini,pk1]=pdetect(pdelay,sube1,bkl,bkh,FALSE);    
        else 
            bkl=1; bkh=pcbsize;                         % Full pitch search 
            % Routine searching integer pitch delay and gain 
            [pcodei,pgaini,pk1]=pdetect(pdelay,sube1,bkl,bkh,FALSE);     
            prev=0; 
        end 
 
    % Fractional pitch delay search 
     
    bkl=max((pcodei-frange/2),bkl);                      % Define fractional pitch delay search (small range:6) 
    bkh=min((pcodei+frange/2-1),bkh); 
     
    % Routine searching fractional pitch delay and gain. Fractional and integer search use the same routine, 
    % which differentiate itself with boolean flag TRUE/FALSE 
    [pcodef,pgainf,pk2]=pdetect(pdelay,sube1,bkl,bkh,TRUE); % 
     
    if pk2<=pk1                                          % Compare results from the integer and fractional searches 
        pcode(sub_cnt)=pcodei-prev;                      % Select the better estimate of pitch delay and gain 
        pgain(sub_cnt)=pgaini; 
        prev=pcodei; 
    else 
        pcode(sub_cnt)=pcodef-prev; 
        pgain(sub_cnt)=pgainf; 
        prev=pcodef; 
    end 
     
end