my_EZW_haar.rar_EZW 压缩_haar transform_site:en.pudn.com_小波 解压缩_小波

I=imread('lena64.bmp'); I=double(I); [ca,ch,cv,cd]=dwt2(I,'haar'); [ca1,ch1,cv1,cd1]=dwt2(ca,'haar'); I5=[ca1,ch1;cv1,cd1]; X=[I5,ch;cv,cd]; X0=X; Y0=max(X); Y1=max(Y0); threshold=2^fix(log2(Y1)); [aa,bb]=size(X0); sublist=[];%空矩阵 存放重要系数 [xx,yy]=size(X); global N %定义一个全局的N A=mapping(xx);%用迂回扫描构造矩阵A 1-64... [m,n]=size(A); k=1; N=[];%定义一个64*2的矩阵 存放扫描顺序 for k=1:m*n;%1-64个循环 flag=0; for i=1:m; if flag==1; break; end for j=1:n; if A(i,j)==k; N=[N;i,j];%构造N[] flag=1; break; end end end end %R=zeros(8); order=1; threshold0=threshold; while threshold ~= threshold0/2^5, threshold; [D,X,sublist] = dominantpass(X,threshold,sublist); DD{order}=D; %扫描出来的放在DD矩阵里 threshold=threshold/2;%阈值/2 if threshold ==threshold0/2^5, break; end S = subordinatepass(sublist,threshold); SS{order}=S; order=order+1; end global N; [m,n]=size(N); XX=zeros(aa); threshold=threshold0; sublist=[]; for k=1:5; RR=zeros(aa); [a,b]=size(DD{k}); i=1; j=1; while i<=m; if j>b; break; end if RR(N(i,1),N(i,2))==1; i=i+1; else if XX(N(i,1),N(i,2))==0 if DD{k}(j)=='p'; XX(N(i,1),N(i,2))=threshold*1.5; RR(N(i,1),N(i,2))=1; sublist=[sublist;N(i,1),N(i,2)]; end if DD{k}(j)=='n'; XX(N(i,1),N(i,2))=-threshold*1.5; RR(N(i,1),N(i,2))=1; sublist=[sublist;N(i,1),N(i,2)]; end if DD{k}(j)=='z'; RR(N(i,1),N(i,2))=1; end if DD{k}(j)=='t'; RR(N(i,1),N(i,2))=1; if i>0&i<=4 RR=checkchildren(i,RR); else if i>4&i<=m/4; RR=checkchildren2(i,RR); else if i>m/4; RR=checkchildren3(i,RR); end end end end i=i+1; j=j+1; else i=i+1; end end end [xx,yy]=size(sublist); threshold=threshold/2; for i=1:xx; if k==5 | threshold==threshold0/2^6; break; end if SS{k}(i)==1; if XX(sublist(i,1),sublist(i,2))>0; XX(sublist(i,1),sublist(i,2))= XX(sublist(i,1),sublist(i,2))+threshold/2; else XX(sublist(i,1),sublist(i,2))= XX(sublist(i,1),sublist(i,2))-threshold/2; end else if SS{k}(i)==0 if XX(sublist(i,1),sublist(i,2))>0; XX(sublist(i,1),sublist(i,2))= XX(sublist(i,1),sublist(i,2))- threshold/2; else XX(sublist(i,1),sublist(i,2))= XX(sublist(i,1),sublist(i,2))+threshold/2; end end end end T=threshold*2 k XX end Z1=idwt2(XX(1:16,1:16),XX(1:16,17:32),XX(17:32,1:16),XX(17:32,17:32),'haar'); Z2=idwt2(Z1,XX(1:32,33:64),XX(33:64,1:32),XX(33:64,33:64),'haar'); Z2=uint8(Z2); imshow('lena64.bmp') title('原始图像') figure; imshow(Z2) title('压缩后的图像')