xiaobofenjie.txt

这是小波分解与重构的仿真程序

小波分解与重构仿真程序
%×°??zhangwanhongD?o?
%load zhangwanhong; 
load zwhong1.m;
%s=zhangwanhong(1:190);
s=zwhong1';
ls=length(s);
[cA1,cD1]=dwt(s,'db4'); 
A1=upcoef('a','cA1','db4',1,ls); 
D1=upcoef('d','cD1','db4',1,ls);
figure(1);
subplot(1,2,1);plot(A1); title('zwh Approximation A1')
subplot(1,2,2);plot(D1); title('zwh Detail D1')
A0=idwt(cA1,cD1,'db4',ls); 
[C,L]=wavedec(s,3,'db4'); 
cA3=appcoef(C,L,'db4',3); 
cD3=detcoef(C,L,3); 
cD2=detcoef(C,L,2);
cD1=detcoef(C,L,1);
A3=wrcoef('a',C,L,'db4',3); 
D1=wrcoef('d',C,L,'db4',1); 
D2=wrcoef('d',C,L,'db4',2);
D3=wrcoef('d',C,L,'db4',3);
figure(2);
subplot(5,1,1);plot(s);title('decomposition  at level three: s=a3+d3+d2+d1')
subplot(5,1,2);plot(A3);title('zwhong Approximation A3')
subplot(5,1,3);plot(D1);title('zwhong Detail D1')
subplot(5,1,4);plot(D2);title('zwhong Detail D2')
subplot(5,1,5);plot(D3);title('zwhong Detail D3')
A0=waverec(C,L,'db4'); 
err = max(abs(s-A0))
figure(3);
subplot(2,1,1);plot(s);title('zwhong original');axis off
subplot(2,1,2);plot(A3);title('zwhong Level 3 Approximation');  axis off