www.pudn.com > hamm.rar > hamm_dec.m

function [out]=hamm_dec(in) 
H=[1 1 1 0 1 0 0;0 1 1 1 0 1 0; 1 1 0 1 0 0 1]; 
n=length(in); 
out=[]; 
for i=1:n/7 
    a=in((i-1)*7+1:i*7); 
    b=a*H'; 
    b=mod(b,2) 
    val=b(1)*4+b(2)*2+b(3); 
    if val~=0 
       a(val)=~a(val); 
    end 
    out=[out a(1:4)]; 
end