Figure 1 Three windows for the Hurst operator

   3x3 case
    c b c
  d b a b d
    c b c

  5x5 case
  f e d e f
  e c b c e
  d b a b d
  e c b c e
  f e d e f

  7x7 case
    h g h
  f e d e f
h e c b c e h
g d b a b d g
h e c b c e h
  f e d e f
    h g h