hvsynthesis.m

一些个 人收集的小波变换的程序

% wavelet synthesis of a image region
% f0: synthesis lowpass		f1: synthesis highpass
% Ain: input image [M x N]
%      [sr, sc] and [er, ec]  specify the rect region of Ain
%      to be decomposed. 
% diret: horizontal =1 , vertical=-1; 		
% A: output images, only the region is changed
% function [A]=synthesis(f0, f1, Ain, sr, sc, er, ec, diret)


function [A]=hvsynthesis(Ain,sr,sc,er,ec,diret)

f0=[0.037828, -0.023849, -0.110624, 0.377402, 0.852699, 0.377402, -0.110624, -0.023849, 0.037828]  ;
f1=[0.064539, -0.040689,-0.418092, 0.788486, -0.418092, -0.040689, 0.064539];

RRM=(sr+er-1)/2;
CCM=(sc+ec-1)/2;

if (diret < 0),

% 	disp('	vertical synthesis....');	
	clen=(er-sr)+1;
	w1=zeros(clen,1);
	w2=zeros(clen,1);

	for cn=sc:ec,
		w1(2:2:clen)=0;
		w1(1:2:clen)=Ain(sr:RRM, cn);
		w2(1:2:clen)=0;
		w2(2:2:clen)=Ain((RRM+1):er, cn);
		Ain(sr:er, cn)=(mfilter(f0,w1)+mfilter(f1,w2));
	end

else
% 	disp('	horizontal synthesis....');	
	rlen=ec-sc+1;
	w1=zeros(1, rlen);
	w2=zeros(1, rlen);
	for rn=sr:er,
		w1(2:2:rlen)=0;
		w1(1:2:rlen)=Ain(rn, sc:CCM);
		w2(1:2:rlen)=0;
		w2(2:2:rlen)=Ain(rn, (CCM+1):ec);
		Ain(rn, sc:ec)=(mfilter(f0,w1)+mfilter(f1,w2));
	end
end

A=Ain;
return;


%*---------------------------------

function [y]=mfilter(B, x)

len=length(x);
y=zeros(1, len);

[RN CN]=size(x);
if CN==1,
	x=x';
end

flen=length(B);

xe=[ fliplr(x(2:len)), x, fliplr( x(1:(len-1)))];

dd=(flen-1)/2;
yt=filter(B,1, xe);
y=yt( (len+dd):(len+len-1+dd));
if CN==1,
	y=y';
end

return;