Python tensorflow.float32() Examples

def minibatch_stddev_layer(x, group_size=4):
    with tf.variable_scope('MinibatchStddev'):
        group_size = tf.minimum(group_size, tf.shape(x)[0])     # Minibatch must be divisible by (or smaller than) group_size.
        s = x.shape                                             # [NCHW]  Input shape.
        y = tf.reshape(x, [group_size, -1, s[1], s[2], s[3]])   # [GMCHW] Split minibatch into M groups of size G.
        y = tf.cast(y, tf.float32)                              # [GMCHW] Cast to FP32.
        y -= tf.reduce_mean(y, axis=0, keep_dims=True)           # [GMCHW] Subtract mean over group.
        y = tf.reduce_mean(tf.square(y), axis=0)                # [MCHW]  Calc variance over group.
        y = tf.sqrt(y + 1e-8)                                   # [MCHW]  Calc stddev over group.
        y = tf.reduce_mean(y, axis=[1,2,3], keep_dims=True)      # [M111]  Take average over fmaps and pixels.
        y = tf.cast(y, x.dtype)                                 # [M111]  Cast back to original data type.
        y = tf.tile(y, [group_size, 1, s[2], s[3]])             # [N1HW]  Replicate over group and pixels.
        return tf.concat([x, y], axis=1)                        # [NCHW]  Append as new fmap.

#----------------------------------------------------------------------------
# Generator network used in the paper. 

def test_generate_np_caches_graph_computation_for_eps_clip_or_xi(self):

        x_val = np.random.rand(1, 2)
        x_val = np.array(x_val, dtype=np.float32)

        self.attack.generate_np(x_val, eps=.3, num_iterations=10,
                                clip_max=-5.0, clip_min=-5.0,
                                xi=1e-6)

        old_grads = tf.gradients

        def fn(*x, **y):
            raise RuntimeError()
        tf.gradients = fn

        self.attack.generate_np(x_val, eps=.2, num_iterations=10,
                                clip_max=-4.0, clip_min=-4.0,
                                xi=1e-5)

        tf.gradients = old_grads 

def stackedRNN(self, x, dropout, scope, embedding_size, sequence_length, hidden_units):
        n_hidden=hidden_units
        n_layers=3
        # Prepare data shape to match `static_rnn` function requirements
        x = tf.unstack(tf.transpose(x, perm=[1, 0, 2]))
        # print(x)
        # Define lstm cells with tensorflow
        # Forward direction cell

        with tf.name_scope("fw"+scope),tf.variable_scope("fw"+scope):
            stacked_rnn_fw = []
            for _ in range(n_layers):
                fw_cell = tf.nn.rnn_cell.BasicLSTMCell(n_hidden, forget_bias=1.0, state_is_tuple=True)
                lstm_fw_cell = tf.contrib.rnn.DropoutWrapper(fw_cell,output_keep_prob=dropout)
                stacked_rnn_fw.append(lstm_fw_cell)
            lstm_fw_cell_m = tf.nn.rnn_cell.MultiRNNCell(cells=stacked_rnn_fw, state_is_tuple=True)

            outputs, _ = tf.nn.static_rnn(lstm_fw_cell_m, x, dtype=tf.float32)
        return outputs[-1] 

def test_generate_np_targeted_gives_adversarial_example(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), np.random.randint(0, 1, 100)] = 1
        x_adv = self.attack.generate_np(x_val, max_iterations=100,
                                        binary_search_steps=3,
                                        initial_const=1,
                                        clip_min=-5, clip_max=5,
                                        batch_size=100, y_target=feed_labs)

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(np.argmax(feed_labs, axis=1) == new_labs)
                        > 0.9) 

def test_attack_strength(self):
        """
        If clipping is not done at each iteration (not passing clip_min and
        clip_max to fgm), this attack fails by
        np.mean(orig_labels == new_labels) == .39.
        """
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        x_adv = self.attack.generate_np(x_val, eps=1.0, ord=np.inf,
                                        clip_min=0.5, clip_max=0.7,
                                        nb_iter=5)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)
        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1) 

def test_generate_targeted_gives_adversarial_example(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), np.random.randint(0, 1, 100)] = 1
        x = tf.placeholder(tf.float32, x_val.shape)
        y = tf.placeholder(tf.float32, feed_labs.shape)

        x_adv_p = self.attack.generate(x, max_iterations=100,
                                       binary_search_steps=3,
                                       initial_const=1,
                                       clip_min=-5, clip_max=5,
                                       batch_size=100, y_target=y)
        self.assertEqual(x_val.shape, x_adv_p.shape)
        x_adv = self.sess.run(x_adv_p, {x: x_val, y: feed_labs})

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(np.argmax(feed_labs, axis=1) == new_labs)
                        > 0.9) 

def wrap_variable(self, var):
        """wrap layer.w into variables"""
        val = self.lay.w.get(var, None)
        if val is None:
            shape = self.lay.wshape[var]
            args = [0., 1e-2, shape]
            if 'moving_mean' in var:
                val = np.zeros(shape)
            elif 'moving_variance' in var:
                val = np.ones(shape)
            else:
                val = np.random.normal(*args)
            self.lay.w[var] = val.astype(np.float32)
            self.act = 'Init '
        if not self.var: return

        val = self.lay.w[var]
        self.lay.w[var] = tf.constant_initializer(val)
        if var in self._SLIM: return
        with tf.variable_scope(self.scope):
            self.lay.w[var] = tf.get_variable(var,
                shape = self.lay.wshape[var],
                dtype = tf.float32,
                initializer = self.lay.w[var]) 

def test_generate_np_targeted_gives_adversarial_example(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), np.random.randint(0, 1, 100)] = 1
        x_adv = self.attack.generate_np(x_val, max_iterations=100,
                                        binary_search_steps=3,
                                        initial_const=1,
                                        clip_min=-5, clip_max=5,
                                        batch_size=100, y_target=feed_labs)

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(np.argmax(feed_labs, axis=1) == new_labs)
                        > 0.9) 

def set_input_shape(self, input_shape):
        batch_size, rows, cols, input_channels = input_shape
        kernel_shape = tuple(self.kernel_shape) + (input_channels,
                                                   self.output_channels)
        assert len(kernel_shape) == 4
        assert all(isinstance(e, int) for e in kernel_shape), kernel_shape
        init = tf.random_normal(kernel_shape, dtype=tf.float32)
        init = init / tf.sqrt(1e-7 + tf.reduce_sum(tf.square(init),
                                                   axis=(0, 1, 2)))
        self.kernels = tf.Variable(init)
        self.b = tf.Variable(
            np.zeros((self.output_channels,)).astype('float32'))
        input_shape = list(input_shape)
        input_shape[0] = 1
        dummy_batch = tf.zeros(input_shape)
        dummy_output = self.fprop(dummy_batch)
        output_shape = [int(e) for e in dummy_output.get_shape()]
        output_shape[0] = batch_size
        self.output_shape = tuple(output_shape) 

def call(self, x):
        if (self.size == None) or (self.mode == 'sum'):
            self.size = int(x.shape[-1])

        position_j = 1. / \
            K.pow(10000., 2 * K.arange(self.size / 2, dtype='float32') / self.size)
        position_j = K.expand_dims(position_j, 0)

        position_i = tf.cumsum(K.ones_like(x[:, :, 0]), 1) - 1
        position_i = K.expand_dims(position_i, 2)
        position_ij = K.dot(position_i, position_j)
        outputs = K.concatenate(
            [K.cos(position_ij), K.sin(position_ij)], 2)

        if self.mode == 'sum':
            if self.scale:
                outputs = outputs * outputs ** 0.5
            return x + outputs
        elif self.mode == 'concat':
            return K.concatenate([outputs, x], 2) 

def _build_input(self):
        self.tails = tf.placeholder(tf.int32, [None])
        self.heads = tf.placeholder(tf.int32, [None])
        self.targets = tf.one_hot(indices=self.heads, depth=self.num_entity)
            
        if not self.query_is_language:
            self.queries = tf.placeholder(tf.int32, [None, self.num_step])
            self.query_embedding_params = tf.Variable(self._random_uniform_unit(
                                                          self.num_query + 1, # <END> token 
                                                          self.query_embed_size), 
                                                      dtype=tf.float32)
        
            rnn_inputs = tf.nn.embedding_lookup(self.query_embedding_params, 
                                                self.queries)
        else:
            self.queries = tf.placeholder(tf.int32, [None, self.num_step, self.num_word])
            self.vocab_embedding_params = tf.Variable(self._random_uniform_unit(
                                                          self.num_vocab + 1, # <END> token
                                                          self.vocab_embed_size),
                                                      dtype=tf.float32)
            embedded_query = tf.nn.embedding_lookup(self.vocab_embedding_params, 
                                                    self.queries)
            rnn_inputs = tf.reduce_mean(embedded_query, axis=2)

        return rnn_inputs 

def noise_input_fn(params):
    """Input function for generating samples for PREDICT mode.

  Generates a single Tensor of fixed random noise. Use tf.data.Dataset to
  signal to the estimator when to terminate the generator returned by
  predict().

  Args:
    params: param `dict` passed by TPUEstimator.

  Returns:
    1-element `dict` containing the randomly generated noise.
  """

    # random noise
    np.random.seed(0)
    noise_dataset = tf.data.Dataset.from_tensors(tf.constant(
        np.random.randn(params['batch_size'], FLAGS.noise_dim), dtype=tf.float32))
    noise = noise_dataset.make_one_shot_iterator().get_next()
    return {'random_noise': noise}, None 

def _mapper(example_proto):
  features = {
      'samples': tf.FixedLenSequenceFeature([1], tf.float32, allow_missing=True),
      'label': tf.FixedLenSequenceFeature([], tf.string, allow_missing=True)
  }
  example = tf.parse_single_example(example_proto, features)

  wav = example['samples'][:, 0]

  wav = wav[:16384]
  wav_len = tf.shape(wav)[0]
  wav = tf.pad(wav, [[0, 16384 - wav_len]])

  label = tf.reduce_join(example['label'], 0)

  return wav, label 

def build_pgd_attack(self, eps):
        victim_embeddings = tf.constant(self.victim_embeddings, dtype=tf.float32)

        def one_step_attack(image, grad):
            """
            core components of this attack are:
            (a) PGD adversarial attack (https://arxiv.org/pdf/1706.06083.pdf)
            (b) momentum (https://arxiv.org/pdf/1710.06081.pdf)
            (c) input diversity (https://arxiv.org/pdf/1803.06978.pdf)
            """
            orig_image = image
            image = self.structure(image)
            image = (image - 127.5) / 128.0
            image = image + tf.random_uniform(tf.shape(image), minval=-1e-2, maxval=1e-2)
            prelogits, _ = self.network.inference(image, 1.0, False, bottleneck_layer_size=512)
            embeddings = tf.nn.l2_normalize(prelogits, 1, 1e-10, name='embeddings')

            embeddings = tf.reshape(embeddings[0], [512, 1])
            objective = tf.reduce_mean(tf.matmul(victim_embeddings, embeddings))  # to be maximized

            noise, = tf.gradients(objective, orig_image)

            noise = noise / tf.reduce_mean(tf.abs(noise), [1, 2, 3], keep_dims=True)
            noise = 0.9 * grad + noise

            adv = tf.clip_by_value(orig_image + tf.sign(noise) * 1.0, lower_bound, upper_bound)
            return adv, noise

        input = tf.to_float(self.image_batch)
        lower_bound = tf.clip_by_value(input - eps, 0, 255.)
        upper_bound = tf.clip_by_value(input + eps, 0, 255.)

        with tf.variable_scope(tf.get_variable_scope(), reuse=tf.AUTO_REUSE):
            adv, _ = tf.while_loop(
                lambda _, __: True, one_step_attack,
                (input, tf.zeros_like(input)),
                back_prop=False,
                maximum_iterations=100,
                parallel_iterations=1)
        self.adv_image = adv
        return adv 

def test_generate_gives_adversarial_example(self):

        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        x = tf.placeholder(tf.float32, x_val.shape)

        x_adv_p = self.attack.generate(x, over_shoot=0.02, max_iter=50,
                                       nb_candidate=2, clip_min=-5, clip_max=5)
        self.assertEqual(x_val.shape, x_adv_p.shape)
        x_adv = self.sess.run(x_adv_p, {x: x_val})

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1) 

def test_generate_gives_adversarial_example(self):

        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), orig_labs] = 1
        x = tf.placeholder(tf.float32, x_val.shape)
        y = tf.placeholder(tf.float32, feed_labs.shape)

        x_adv_p = self.attack.generate(x, max_iterations=100,
                                       binary_search_steps=3,
                                       initial_const=1,
                                       clip_min=-5, clip_max=5,
                                       batch_size=100, y=y)
        self.assertEqual(x_val.shape, x_adv_p.shape)
        x_adv = self.sess.run(x_adv_p, {x: x_val, y: feed_labs})

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1) 

def __init__(self, resolution=1024, num_channels=3, dtype='uint8', dynamic_range=[0,255], label_size=0, label_dtype='float32'):
        self.resolution         = resolution
        self.resolution_log2    = int(np.log2(resolution))
        self.shape              = [num_channels, resolution, resolution]
        self.dtype              = dtype
        self.dynamic_range      = dynamic_range
        self.label_size         = label_size
        self.label_dtype        = label_dtype
        self._tf_minibatch_var  = None
        self._tf_lod_var        = None
        self._tf_minibatch_np   = None
        self._tf_labels_np      = None

        assert self.resolution == 2 ** self.resolution_log2
        with tf.name_scope('Dataset'):
            self._tf_minibatch_var = tf.Variable(np.int32(0), name='minibatch_var')
            self._tf_lod_var = tf.Variable(np.int32(0), name='lod_var') 

def autosummary(name, value):
    id = name.replace('/', '_')
    if is_tf_expression(value):
        with tf.name_scope('summary_' + id), tf.device(value.device):
            update_op = _create_autosummary_var(name, value)
            with tf.control_dependencies([update_op]):
                return tf.identity(value)
    else: # python scalar or numpy array
        if name not in _autosummary_immediate:
            with absolute_name_scope('Autosummary/' + id), tf.device(None), tf.control_dependencies(None):
                update_value = tf.placeholder(tf.float32)
                update_op = _create_autosummary_var(name, update_value)
                _autosummary_immediate[name] = update_op, update_value
        update_op, update_value = _autosummary_immediate[name]
        run(update_op, {update_value: np.float32(value)})
        return value

# Create the necessary ops to include autosummaries in TensorBoard report.
# Note: This should be done only once per graph. 

def _create_autosummary_var(name, value_expr):
    assert not _autosummary_finalized
    v = tf.cast(value_expr, tf.float32)
    if v.shape.ndims is 0:
        v = [v, np.float32(1.0)]
    elif v.shape.ndims is 1:
        v = [tf.reduce_sum(v), tf.cast(tf.shape(v)[0], tf.float32)]
    else:
        v = [tf.reduce_sum(v), tf.reduce_prod(tf.cast(tf.shape(v), tf.float32))]
    v = tf.cond(tf.is_finite(v[0]), lambda: tf.stack(v), lambda: tf.zeros(2))
    with tf.control_dependencies(None):
        var = tf.Variable(tf.zeros(2)) # [numerator, denominator]
    update_op = tf.cond(tf.is_variable_initialized(var), lambda: tf.assign_add(var, v), lambda: tf.assign(var, v))
    if name in _autosummary_vars:
        _autosummary_vars[name].append(var)
    else:
        _autosummary_vars[name] = [var]
    return update_op

#----------------------------------------------------------------------------
# Call filewriter.add_summary() with all summaries in the default graph,
# automatically finalizing and merging them on the first call. 

def test_generate_gives_adversarial_example(self):

        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), orig_labs] = 1
        x = tf.placeholder(tf.float32, x_val.shape)
        y = tf.placeholder(tf.float32, feed_labs.shape)

        x_adv_p = self.attack.generate(x, max_iterations=100,
                                       binary_search_steps=3,
                                       initial_const=1,
                                       clip_min=-5, clip_max=5,
                                       batch_size=100, y=y)
        self.assertEqual(x_val.shape, x_adv_p.shape)
        x_adv = self.sess.run(x_adv_p, {x: x_val, y: feed_labs})

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1) 

def test_generate_np_targeted_gives_adversarial_example(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        feed_labs = np.zeros((100, 2))
        feed_labs[np.arange(100), np.random.randint(0, 1, 100)] = 1
        x_adv = self.attack.generate_np(x_val, max_iterations=100,
                                        binary_search_steps=3,
                                        initial_const=1,
                                        clip_min=-5, clip_max=5,
                                        batch_size=100, y_target=feed_labs)

        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)

        self.assertTrue(np.mean(np.argmax(feed_labs, axis=1) == new_labs) >
                        0.9) 

def test_attack_strength(self):
        """
        If clipping is not done at each iteration (not using clip_min and
        clip_max), this attack fails by
        np.mean(orig_labels == new_labels) == .5
        """
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        x_adv = self.attack.generate_np(x_val, eps=1.0, eps_iter=0.05,
                                        clip_min=0.5, clip_max=0.7,
                                        nb_iter=5)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)
        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1) 

def test_generate_np_high_confidence_targeted_examples(self):

        trivial_model = TrivialModel()

        for CONFIDENCE in [0, 2.3]:
            x_val = np.random.rand(10, 1) - .5
            x_val = np.array(x_val, dtype=np.float32)

            feed_labs = np.zeros((10, 2))
            feed_labs[np.arange(10), np.random.randint(0, 2, 10)] = 1
            attack = CarliniWagnerL2(trivial_model, sess=self.sess)
            x_adv = attack.generate_np(x_val,
                                       max_iterations=100,
                                       binary_search_steps=2,
                                       learning_rate=1e-2,
                                       initial_const=1,
                                       clip_min=-10, clip_max=10,
                                       confidence=CONFIDENCE,
                                       y_target=feed_labs,
                                       batch_size=10)

            new_labs = self.sess.run(trivial_model.get_logits(x_adv))

            good_labs = new_labs[np.arange(10), np.argmax(feed_labs, axis=1)]
            bad_labs = new_labs[np.arange(
                10), 1 - np.argmax(feed_labs, axis=1)]

            self.assertClose(CONFIDENCE, np.min(good_labs - bad_labs),
                             atol=1e-1)
            self.assertTrue(np.mean(np.argmax(new_labs, axis=1) ==
                                    np.argmax(feed_labs, axis=1)) > .9) 

def test_generate_np_can_be_called_with_different_decay_factor(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        for dacay_factor in [0.0, 0.5, 1.0]:
            x_adv = self.attack.generate_np(x_val, eps=0.5, ord=np.inf,
                                            dacay_factor=dacay_factor,
                                            clip_min=-5.0, clip_max=5.0)

            delta = np.max(np.abs(x_adv - x_val), axis=1)
            self.assertClose(delta, 0.5) 

def generate_adversarial_examples_np(self, ord, eps, **kwargs):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        x_adv = self.attack.generate_np(x_val, eps=eps, ord=ord,
                                        clip_min=-5, clip_max=5, **kwargs)
        if ord == np.inf:
            delta = np.max(np.abs(x_adv - x_val), axis=1)
        elif ord == 1:
            delta = np.sum(np.abs(x_adv - x_val), axis=1)
        elif ord == 2:
            delta = np.sum(np.square(x_adv - x_val), axis=1)**.5

        return x_val, x_adv, delta 

def test_generate_np_does_not_cache_graph_computation_for_nb_iter(self):

        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        x_adv = self.attack.generate_np(x_val, eps=1.0, ord=np.inf,
                                        clip_min=-5.0, clip_max=5.0,
                                        nb_iter=10)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)
        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1)

        ok = [False]
        old_grads = tf.gradients

        def fn(*x, **y):
            ok[0] = True
            return old_grads(*x, **y)
        tf.gradients = fn

        x_adv = self.attack.generate_np(x_val, eps=1.0, ord=np.inf,
                                        clip_min=-5.0, clip_max=5.0,
                                        nb_iter=11)

        orig_labs = np.argmax(self.sess.run(self.model(x_val)), axis=1)
        new_labs = np.argmax(self.sess.run(self.model(x_adv)), axis=1)
        self.assertTrue(np.mean(orig_labs == new_labs) < 0.1)

        tf.gradients = old_grads

        self.assertTrue(ok[0]) 

def test_generate_np_high_confidence_untargeted_examples(self):

        trivial_model = TrivialModel()

        for CONFIDENCE in [0, 2.3]:
            x_val = np.random.rand(10, 1) - .5
            x_val = np.array(x_val, dtype=np.float32)

            orig_labs = np.argmax(self.sess.run(trivial_model.get_logits(x_val)), axis=1)
            attack = CarliniWagnerL2(trivial_model, sess=self.sess)
            x_adv = attack.generate_np(x_val,
                                       max_iterations=100,
                                       binary_search_steps=2,
                                       learning_rate=1e-2,
                                       initial_const=1,
                                       clip_min=-10, clip_max=10,
                                       confidence=CONFIDENCE,
                                       batch_size=10)

            new_labs = self.sess.run(trivial_model.get_logits(x_adv))

            good_labs = new_labs[np.arange(10), 1 - orig_labs]
            bad_labs = new_labs[np.arange(10), orig_labs]

            self.assertTrue(np.mean(np.argmax(new_labs, axis=1) == orig_labs)
                            == 0)
            self.assertTrue(np.isclose(
                0, np.min(good_labs - (bad_labs + CONFIDENCE)), atol=1e-1)) 

def test_generate_np_can_be_called_with_different_eps(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        for eps in [0.1, 0.2, 0.3, 0.4]:
            x_adv = self.attack.generate_np(x_val, eps=eps, ord=np.inf,
                                            clip_min=-5.0, clip_max=5.0)

            delta = np.max(np.abs(x_adv - x_val), axis=1)
            self.assertClose(delta, eps) 

def get_logits(new_input, length, first=[]):
    """
    Compute the logits for a given waveform.

    First, preprocess with the TF version of MFC above,
    and then call DeepSpeech on the features.
    """
    # new_input = tf.Print(new_input, [tf.shape(new_input)])

    # We need to init DeepSpeech the first time we're called
    if first == []:
        first.append(False)
        # Okay, so this is ugly again.
        # We just want it to not crash.
        tf.app.flags.FLAGS.alphabet_config_path = "DeepSpeech/data/alphabet.txt"
        DeepSpeech.initialize_globals()
        print('initialized deepspeech globals')

    batch_size = new_input.get_shape()[0]

    # 1. Compute the MFCCs for the input audio
    # (this is differentable with our implementation above)
    empty_context = np.zeros((batch_size, 9, 26), dtype=np.float32)
    new_input_to_mfcc = compute_mfcc(new_input)[:, ::2]
    features = tf.concat((empty_context, new_input_to_mfcc, empty_context), 1)

    # 2. We get to see 9 frames at a time to make our decision,
    # so concatenate them together.
    features = tf.reshape(features, [new_input.get_shape()[0], -1])
    features = tf.stack([features[:, i:i+19*26] for i in range(0,features.shape[1]-19*26+1,26)],1)
    features = tf.reshape(features, [batch_size, -1, 19*26])

    # 3. Whiten the data
    mean, var = tf.nn.moments(features, axes=[0,1,2])
    features = (features-mean)/(var**.5)

    # 4. Finally we process it with DeepSpeech
    logits = DeepSpeech.BiRNN(features, length, [0]*10)

    return logits 

def test_generate_np_gives_clipped_adversarial_examples(self):
        x_val = np.random.rand(100, 2)
        x_val = np.array(x_val, dtype=np.float32)

        x_adv = self.attack.generate_np(x_val, max_iterations=10,
                                        binary_search_steps=1,
                                        learning_rate=1e-3,
                                        initial_const=1,
                                        clip_min=-0.2, clip_max=0.3,
                                        batch_size=100)

        self.assertTrue(-0.201 < np.min(x_adv))
        self.assertTrue(np.max(x_adv) < .301)