from Image Zoomin by Ahmed Samieh
Digital Image Zoomin (gray and color images)

zoomout(I)
function R = zoomout(I)
  [i,j] = size(I);
  for row = 1 : uint16(i/2)
    for col = 1 : uint16(j/2)
      R(row, col) = I(row+row-1, col+col-1);
    end
  end
return

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