'Args:
horiz_frac (float): max abs fraction for horizontal shift
vert_frac (float): max abs fraction for horizontal shift
border: cv2 border method
border_value: cv2 border value for border=cv2.BORDER_CONSTANT'

def __init__(self, horiz_frac=0, vert_frac=0, border=cv2.BORDER_REPLICATE, border_value=0):

    assert ((horiz_frac < 1.0) and (vert_frac < 1.0))
    super(Shift, self).__init__()
    self._init(locals())
