uw_sb_unwrap_space_time.m

来自「StaMps最新测试版」· M 代码 · 共 95 行

function []=uw_sb_unwrap_time(day,ifgday_ix,unwrap_method,time_win)
%UW_SB_UNWRAP_SPACE_TIME smooth and unwrap phase diffs between neighboring data points in time
%
%   Andy Hooper, June 2007
%
%   ======================================================================
%   07/2008 AH: Allow isolated images, not included in any interferogram
%   ======================================================================

tic

disp('Unwrapping in time-space...')

uw=load('uw_grid');
ui=load('uw_interp');

n_ifg=uw.n_ifg;
n_image=size(day,1);
master_ix=find(day==0);

day_pos_ix=find(day>0);
[Y,I]=min(day(day_pos_ix));
dph_noise=zeros(ui.n_edge,uw.n_ifg,'single');
dph_space=((uw.ph(ui.edges(:,3),:).*conj(uw.ph(ui.edges(:,2),:))));
ph_noise=angle(uw.ph.*conj(uw.ph_lowpass));
clear uw
dph_noise_sf=((ph_noise(ui.edges(:,3),:)-(ph_noise(ui.edges(:,2),:))));
dph_space=dph_space./abs(dph_space);


if strcmpi(unwrap_method,'2D')
    save('uw_space_time','dph_space');
elseif strcmpi(unwrap_method,'3D_NO_DEF')
    dph_noise=angle(dph_space);
    dph_space_uw=angle(dph_space);
    save('uw_space_time','dph_space','dph_space_uw','dph_noise');
else
    G=zeros(n_ifg,n_image);
    for i=1:n_ifg
        G(i,ifgday_ix(i,1))=-1;
        G(i,ifgday_ix(i,2))=1;
    end

    nzc_ix=sum(abs(G))~=0; % non-zero column index
    day=day(nzc_ix);
    G=G(:,nzc_ix);
    n=size(G,2);
    
    
    dph_space_series=[zeros(1,ui.n_edge);double(G(:,2:end))\double(angle(dph_space))'];
    dph_smooth_series=zeros(size(G,2),ui.n_edge,'single');

    for i1=1:n
        time_diff_sq=(day(i1)-day).^2;
        weight_factor=exp(-time_diff_sq/2/time_win^2);
        weight_factor=weight_factor/sum(weight_factor);
        dph_smooth_series(i1,:)=sum(dph_space_series.*repmat(weight_factor,1,ui.n_edge));
    end

    dph_smooth_ifg=(G*dph_smooth_series)';
    dph_noise=angle(dph_space.*exp(-j*dph_smooth_ifg));


    if strcmpi(unwrap_method,'3D_SMALL_DEF')|...
       strcmpi(unwrap_method,'3D_QUICK')
      not_small_ix=find(std(dph_noise,0,2)>1.3)';
      fprintf('Ignoring %d edges. Elapsed time = %d s\n',length(not_small_ix),round(toc))
      dph_noise(not_small_ix,:)=nan;
    else
      m_minmax=repmat([-pi,pi],5,1).*repmat([0.5;0.25;1;0.25;1],1,2);
      anneal_opts=[1;15;0;0;0;0;0];
      covm=cov((dph_noise_sf)); % estimate of covariance
      W=chol(inv(covm)); % weighting matrix 
      not_small_ix=find(std(dph_noise,0,2)>1)';
      fprintf('Performing more complex smoothing on %d edges. Elapsed time = %d s\n',length(not_small_ix),round(toc))

      n_proc=0;
      for i=not_small_ix
        dph=angle(dph_space(i,:))';
        dph_smooth_series(:,i)=uw_sb_smooth_unwrap(m_minmax,anneal_opts,G,W,dph,x);

        n_proc=n_proc+1;
        if round(n_proc/1000)==n_proc/1000
            save('uw_unwrap_time','G','dph_space','dph_smooth_series');
            fprintf('%d edges of %d reprocessed. Elapsed time = %d s\n',n_proc,length(not_small_ix),round(toc))
        end
      end
      dph_smooth_ifg=(G*dph_smooth_series)';
      dph_noise=angle(dph_space.*exp(-j*dph_smooth_ifg));
    end
    dph_space_uw=dph_smooth_ifg+dph_noise;

    save('uw_space_time','dph_space','dph_space_uw','dph_noise','G','dph_smooth_series');
end