import tensorflow as tf

            self.epsilon = epsilon
            self.name = name
            self.mean = tf.reduce_mean(x, [0, 1, 2], keep_dims=True)
            self.mean_sq = tf.reduce_mean(tf.square(x), [0, 1, 2], keep_dims=True)
            self.batch_size = int(x.get_shape()[0])
            assert x is not None
