mm=16;
%% CONSTRUCT transform matrix ww
h=wfilters('db1','l');
rank=log2(mm);
ww=1;
for jj=1:4%如果是二階分解的話就是jj=3:4
    nn=2^jj;
    clear w1 p1 p2 p1_0 p2_0;
    for ii=1:length(h)
        p1_0(ii)=h(length(h)-ii+1);
        p2_0(ii)=(-1)^ii*h(ii);
    end
    p1_0=sparse([p1_0,zeros(1,nn-length(h))]);
    p2_0=sparse([p2_0,zeros(1,nn-length(h))]);

    for ii=1:nn/2
        p1(ii,:)=circshift(p1_0',2*(ii-1))';
        p2(ii,:)=circshift(p2_0',2*(ii-1))';
    end
    w1=[p2;p1];
    clear p1;
    clear p2;
    L=2^rank-length(w1);
    w=sparse([eye(L,L),zeros(L,length(w1));zeros(length(w1),L),w1;]);
    ww=ww*w;
    clear w;
end
%這種小波構(gòu)造方式適合于各種DB系列的小波，但面對(duì)db6等比較長(zhǎng)的小波，則均衡器的權(quán)長(zhǎng)要足夠長(zhǎng)。