in augment/effects.py [0:0]
def __call__(self, x, src_info, dst_info):
factor = self.clamp_factor() if callable(self.clamp_factor) else self.clamp_factor
x_min, x_max = x.min(), x.max()
x.clamp_(min=x_min * factor, max=x_max * factor)
return x, src_info, dst_info