matlab小波變換clear all clc tic load a; for i=1:8 [cA1,cH1,cV1,cD1]=dwt2(a{i},'db1'); %第一次分解 dec1d=[cA1,cH1;cV1,cD1]; [cA2,cH2,cV2,cD2]=dwt2(cA1,'db1'); %第二次分解 dec2d=[cA2,cH2;cV2,cD2]; data_save(1,i)={cA2}; data_save(2,i)={cH2}; data_save(3,i)={cV2}; data_save(4,i)={cD2}; data_save(5,i)={cA1}; data_sa