www.pudn.com > multiwavelet.rar > rec2D_pe.m

function fhatp=rec2D_pe(transf,flt,maxlevel) 
%fhatp=rec2D_pe(transf,flt,maxlevel) 
% 
%  This function reconstructs preprocessed 2-dimensional signal from its  
%  discrete multiwavelet transform. Boundaries are handled by periodic  
%  extension. For description of the algorithm see [SW] 
% 
%  Input: 
%    maxlevel    integer, number of levels of decomposition  
%    flt         string of characters, name of the filter bank; 
%                for possible names and short descriptions see coef.m 
%    transf      n by n real array, multiscaling and multiwavelet coefficients; 
%                for structure of transf see [SW]  
%                n must be of the form integer*2^maxlevel 
% 
%  Output:  
%    fhatp       n by n real array, reconstructed preprocessed signal; 
%                for structure of fhatp see [SW] 
% 
%  Example of Usage: 
%    fhatp=rec2D_pe(transf,'cl',3) 
 
% Author: Vasily Strela 
% COPYRIGHT 1997,98 by Vasily Strela 
 
[n1,n2]=size(transf); 
n1=n1/2^(maxlevel-1); 
n2=n2/2^(maxlevel-1); 
 
[L,H]=coef(flt); 
[nf,ns]=size(L); 
 
fhatp=transf; 
for lv=1:maxlevel 
  nh=n1/nf; 
  aa=zeros(nf,nh); 
  for l=1:n2 
    for j=1:nf 
      aa(j,1:nh/2)=fhatp((j-1)*nh/2+1:j*nh/2,l)'; 
      aa(j,nh/2+1:nh)=fhatp(n1/2+(j-1)*nh/2+1:n1/2+j*nh/2,l)';     
    end 
    aa=rec1D_pe(aa,flt,1); 
    for j=1:nf 
      fhatp((j-1)*nh+1:j*nh,l)=aa(j,:)'; 
    end 
  end 
  nh=n2/nf; 
  aa=zeros(nf,nh); 
  for l=1:n1 
    for j=1:nf 
      aa(j,1:nh/2)=fhatp(l,(j-1)*nh/2+1:j*nh/2); 
      aa(j,nh/2+1:nh)=fhatp(l,n2/2+(j-1)*nh/2+1:n2/2+j*nh/2);     
    end 
    aa=rec1D_pe(aa,flt,1); 
    for j=1:nf 
      fhatp(l,(j-1)*nh+1:j*nh)=aa(j,:); 
    end 
  end 
  n1=n1*2; 
  n2=n2*2; 
end