waveup2.m

小波变换通过matlab实现s小波变换代码

%function wvlet=waveup2(x)
function [ll,hl,lh,hh]=waveup2(x)
x=double(x);
wvlet=x;
[hp,lp]=size(x);
hc=hp/2;
lc=lp/2;
%奇偶列重排
for n=1:lc
	j=n*2-1;
	wvlet(:,n)=x(:,j);
	wvlet(:,lc+n)=x(:,j+1);
end
%行变换开始
for n=1:lc-1	
	k=(wvlet(:,n)+wvlet(:,n+1))/2;
	wvlet(:,lc+n)=wvlet(:,lc+n)-k;
end
	k=(wvlet(:,lc)+wvlet(:,lc-1))/2;    
	wvlet(:,lp)=wvlet(:,lp)-k;

	k=(wvlet(:,lc+2)+wvlet(:,lc+1))/4;
	wvlet(:,1)=wvlet(:,1)+k;
for n=2:lc
	k=(wvlet(:,lc+n)+wvlet(:,lc+n-1))/4;
	wvlet(:,n)=wvlet(:,n)+k;
end
%行变换结束
x=wvlet;
%奇偶行重排
for n=1:hc
	j=n*2-1;
	wvlet(n,:)=x(j,:);
	wvlet(hc+n,:)=x(j+1,:);
end
%列重排开始	
for n=1:hc-1	
	k=(wvlet(n,:)+wvlet(n+1,:))/2;
	wvlet(hc+n,:)=wvlet(hc+n,:)-k;
end
	k=(wvlet(hc,:)+wvlet(hc-1,:))/2;
	wvlet(hp,:)=wvlet(hp,:)-k;

	k=(wvlet(hc+2,:)+wvlet(hc+1,:))/4;
	wvlet(1,:)=wvlet(1,:)+k;
for n=2:hc
	k=(wvlet(hc+n,:)+wvlet(hc+n-1,:))/4;
	wvlet(n,:)=wvlet(n,:)+k;
end
%列重排结束
%wvlet=uint8(wvlet);
ll=wvlet(1:hc,1:lc);
hl=wvlet(1:hc,lc+1:lp);
lh=wvlet(hc+1:hp,1:lc);
hh=wvlet(hc+1:hp,lc+1:lp);