function filtered = demosaicPDI(img)


A = im2double(img);
[rows,cols] = size(A);
cols = cols / 3;

for x = 1:2:cols
    for y = 1:2:rows
        A(y,x,1) = A(y+1,x+1,1);
        A(y,x,2) = A(y,x+1,2);
        A(y+1,x,1) = A(y+1,x+1,1);
        A(y+1,x,3) = A(y,x,3);
        A(y,x+1,1) = A(y+1,x+1,1);
        A(y,x+1,3) = A(y,x,3);
        A(y+1,x+1,2) = A(y+1,x,2);
        A(y+1,x+1,3) = A(y,x,3);
    end
end


filtered = A;