function imden=den2d_TI(Image,qmf,scale,type,Sigma,thd)
% Term-by-term image denoising in the TI-wavelet domain.
%
% 	Input
%		Image	Input image.
%		qmf	QMF filter.
%		scale	Coarsest decomposition scale.
%		type	Hard or soft thresholding ('H' (default) 'S').
%		Sigma	Noise std (default, estimated by MAD).
%		thd	Threshold (default, 4 at finest scale and 3 at all other scales).
%
%	Output
%		imden	Denoised image.
% 
if (exist('Image','var')~=1), error('Provide input image'); end;

[M,N]=size(Image);

if (exist('scale','var')~=1), scale=floor(log2(min(M,N)))-3; end;
if (exist('qmf','var')~=1), qmf=MakeONFilter('Symmlet',6); end;
if (exist('type','var')~=1), type='H'; end;
if (~strcmp(type,'S') & ~strcmp(type,'H')), error('Only hard or soft thresholding handled.'); end;

J=nextpow2(min(M,N));
[ll,wc,L] = mrdwt(Image,qmf,J-scale);

if (exist('Sigma','var')~=1),
	% To estimate the WGN standard deviation using the MAD.
	HH = wc(:,2*N+1:3*N);
	HH_reshp = reshape(HH, M*N, 1);
	Sigma = std(HH_reshp);
end

if ~exist('thd','var')
 thd=3*ones(J-scale,1)*Sigma;
 thd(1)=4*Sigma;
elseif isscalar(thd)
  thd=thd*ones(J-scale,1);
end

for i = 1:J-scale
 HH = wc(:,(i-1)*3*N+2*N+1:(i-1)*3*N+3*N);
 if(strcmp(type,'S')) Thr_wc_Noisy = SoftThresh(HH,thd(i));
 else Thr_wc_Noisy = HardThresh(HH,thd(i)); end;
 wc(:,(i-1)*3*N+2*N+1:(i-1)*3*N+3*N) = Thr_wc_Noisy;
 
 HL = wc(:,(i-1)*3*N+N+1:(i-1)*3*N+2*N);
 if(strcmp(type,'S')) Thr_wc_Noisy = SoftThresh(HL,thd(i));
 else Thr_wc_Noisy = HardThresh(HL,thd(i)); end;
 wc(:,(i-1)*3*N+N+1:(i-1)*3*N+2*N) = Thr_wc_Noisy;
 
 LH = wc(:,(i-1)*3*N+1:(i-1)*3*N+N);
 if(strcmp(type,'S')) Thr_wc_Noisy = SoftThresh(LH,thd(i));
 else Thr_wc_Noisy = HardThresh(LH,thd(i)); end;
 wc(:,(i-1)*3*N+1:(i-1)*3*N+N) = Thr_wc_Noisy;
end

imden = mirdwt(ll,wc,qmf,J-scale);

%
% Part of DBlockToolbox Version:100
% Written by: Jalal Fadili, GREYC CNRS ENSICAEN
%             Christophe Chesneau, LMNO University of Caen
%             Jean-Luc Starck, CEA-CNRS
% Created June 2008
% This material is distributed under CeCiLL licence.
% E-mail: Jalal.Fadili@greyc.ensicaen.fr
%