buildGpyr1_matrix_meta.m

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% Created by Jonathan T Barron and Jitendra Malik, Electrical Engineering
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function [meta] = buildGpyr(sz, depth, filt, edges)

meta.pind = {sz};
for d = 2:depth
  meta.pind{d} = ceil(meta.pind{d-1}/2);
end
meta.pind = cat(1, meta.pind{:});

for d = 2:depth
  
  A = conv2mat_edges([meta.pind(d-1),1], filt(:), edges, [2,1]);
  
  meta.A{d-1} = A;
  meta.AT{d-1} = A';
  
end

Ac = {speye(meta.pind(1,:), meta.pind(1,:))};
for s = 1:length(meta.A)
  Ac{s+1} = meta.A{s} * Ac{s};
end

meta.Ac = cat(1,Ac{:});
meta.AcT = meta.Ac';