import tensorflow as tf

    cdf_plus = tf.nn.sigmoid(plus_in)
    min_in = inv_stdv * (centered_inputs - 1. / 255.)
    cdf_min = tf.nn.sigmoid(min_in)
    log_cdf_plus = plus_in - tf.nn.softplus(plus_in)
    log_one_minus_cdf_min = -tf.nn.softplus(min_in)
    cdf_delta = cdf_plus - cdf_min
