def forget_xy ( t ) : shape = ( t . shape [ 0 ] , None , None , t . shape [ 3 ] ) return tf . placeholder_with_default ( t , shape )
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Ignore sizes of dimensions ( 1 2 ) of a 4d tensor in shape inference .
def forget_xy(t):
  """Ignore sizes of dimensions (1, 2) of a 4d tensor in shape inference.

  This allows using smaller input sizes, which create an invalid graph at higher
  layers (for example because a spatial dimension becomes smaller than a conv
  filter) when we only use early parts of it.
  """
  shape = (t.shape[0], None, None, t.shape[3])
  return tf.placeholder_with_default(t, shape)