Exemple #1
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def decode_predictions(preds, top=5):
    LABELS = None
    if len(preds.shape) == 2:
        if preds.shape[1] == 2622:
            fpath = get_file('rcmalli_vggface_labels_v1.npy',
                             V1_LABELS_PATH,
                             cache_subdir=VGGFACE_DIR)
            LABELS = np.load(fpath)
        elif preds.shape[1] == 8631:
            fpath = get_file('rcmalli_vggface_labels_v2.npy',
                             V2_LABELS_PATH,
                             cache_subdir=VGGFACE_DIR)
            LABELS = np.load(fpath)
        else:
            raise ValueError('`decode_predictions` expects '
                             'a batch of predictions '
                             '(i.e. a 2D array of shape (samples, 2622)) for V1 or '
                             '(samples, 8631) for V2.'
                             'Found array with shape: ' + str(preds.shape))
    else:
        raise ValueError('`decode_predictions` expects '
                         'a batch of predictions '
                         '(i.e. a 2D array of shape (samples, 2622)) for V1 or '
                         '(samples, 8631) for V2.'
                         'Found array with shape: ' + str(preds.shape))
    results = []
    for pred in preds:
        top_indices = pred.argsort()[-top:][::-1]
        result = [[str(LABELS[i].encode('utf8')), pred[i]] for i in top_indices]
        result.sort(key=lambda x: x[1], reverse=True)
        results.append(result)
    return results
Exemple #2
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def load_data():
  """Loads CIFAR10 dataset.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
  dirname = 'cifar-10-batches-py'
  origin = 'http://www.cs.toronto.edu/~kriz/cifar-10-python.tar.gz'
  path = get_file(dirname, origin=origin, untar=True)

  num_train_samples = 50000

  x_train = np.zeros((num_train_samples, 3, 32, 32), dtype='uint8')
  y_train = np.zeros((num_train_samples,), dtype='uint8')

  for i in range(1, 6):
    fpath = os.path.join(path, 'data_batch_' + str(i))
    data, labels = load_batch(fpath)
    x_train[(i - 1) * 10000:i * 10000, :, :, :] = data
    y_train[(i - 1) * 10000:i * 10000] = labels

  fpath = os.path.join(path, 'test_batch')
  x_test, y_test = load_batch(fpath)

  y_train = np.reshape(y_train, (len(y_train), 1))
  y_test = np.reshape(y_test, (len(y_test), 1))

  if K.image_data_format() == 'channels_last':
    x_train = x_train.transpose(0, 2, 3, 1)
    x_test = x_test.transpose(0, 2, 3, 1)

  return (x_train, y_train), (x_test, y_test)
Exemple #3
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def decode_predictions(preds, top=5):
  """Decodes the prediction of an ImageNet model.

  Arguments:
      preds: Numpy tensor encoding a batch of predictions.
      top: integer, how many top-guesses to return.

  Returns:
      A list of lists of top class prediction tuples
      `(class_name, class_description, score)`.
      One list of tuples per sample in batch input.

  Raises:
      ValueError: in case of invalid shape of the `pred` array
          (must be 2D).
  """
  global CLASS_INDEX
  if len(preds.shape) != 2 or preds.shape[1] != 1000:
    raise ValueError('`decode_predictions` expects '
                     'a batch of predictions '
                     '(i.e. a 2D array of shape (samples, 1000)). '
                     'Found array with shape: ' + str(preds.shape))
  if CLASS_INDEX is None:
    fpath = get_file('imagenet_class_index.json',
                     CLASS_INDEX_PATH,
                     cache_subdir='models',
                     file_hash='c2c37ea517e94d9795004a39431a14cb')
    CLASS_INDEX = json.load(open(fpath))
  results = []
  for pred in preds:
    top_indices = pred.argsort()[-top:][::-1]
    result = [tuple(CLASS_INDEX[str(i)]) + (pred[i],) for i in top_indices]
    result.sort(key=lambda x: x[2], reverse=True)
    results.append(result)
  return results
Exemple #4
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def load_data(path='boston_housing.npz', test_split=0.2, seed=113):
    """Loads the Boston Housing dataset.

  Arguments:
      path: path where to cache the dataset locally
          (relative to ~/.keras/datasets).
      test_split: fraction of the data to reserve as test set.
      seed: Random seed for shuffling the data
          before computing the test split.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
    assert 0 <= test_split < 1
    path = get_file(
        path,
        origin='https://s3.amazonaws.com/keras-datasets/boston_housing.npz',
        file_hash=
        'f553886a1f8d56431e820c5b82552d9d95cfcb96d1e678153f8839538947dff5')
    f = np.load(path)
    x = f['x']
    y = f['y']
    f.close()

    np.random.seed(seed)
    indices = np.arange(len(x))
    np.random.shuffle(indices)
    x = x[indices]
    y = y[indices]

    x_train = np.array(x[:int(len(x) * (1 - test_split))])
    y_train = np.array(y[:int(len(x) * (1 - test_split))])
    x_test = np.array(x[int(len(x) * (1 - test_split)):])
    y_test = np.array(y[int(len(x) * (1 - test_split)):])
    return (x_train, y_train), (x_test, y_test)
Exemple #5
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def load_data(label_mode='fine'):
    """Loads CIFAR100 dataset.

  Arguments:
      label_mode: one of "fine", "coarse".

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case of invalid `label_mode`.
  """
    if label_mode not in ['fine', 'coarse']:
        raise ValueError('`label_mode` must be one of `"fine"`, `"coarse"`.')

    dirname = 'cifar-100-python'
    origin = 'https://www.cs.toronto.edu/~kriz/cifar-100-python.tar.gz'
    path = get_file(dirname, origin=origin, untar=True)

    fpath = os.path.join(path, 'train')
    x_train, y_train = load_batch(fpath, label_key=label_mode + '_labels')

    fpath = os.path.join(path, 'test')
    x_test, y_test = load_batch(fpath, label_key=label_mode + '_labels')

    y_train = np.reshape(y_train, (len(y_train), 1))
    y_test = np.reshape(y_test, (len(y_test), 1))

    if K.image_data_format() == 'channels_last':
        x_train = x_train.transpose(0, 2, 3, 1)
        x_test = x_test.transpose(0, 2, 3, 1)

    return (x_train, y_train), (x_test, y_test)
def load_data():
  """Loads the Fashion-MNIST dataset.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
  dirname = os.path.join('datasets', 'fashion-mnist')
  base = 'http://fashion-mnist.s3-website.eu-central-1.amazonaws.com/'
  files = [
      'train-labels-idx1-ubyte.gz', 'train-images-idx3-ubyte.gz',
      't10k-labels-idx1-ubyte.gz', 't10k-images-idx3-ubyte.gz'
  ]

  paths = []
  for given_file in files:
    paths.append(
        get_file(given_file, origin=base + given_file, cache_subdir=dirname))

  with gzip.open(paths[0], 'rb') as lbpath:
    y_train = np.frombuffer(lbpath.read(), np.uint8, offset=8)

  with gzip.open(paths[1], 'rb') as imgpath:
    x_train = np.frombuffer(
        imgpath.read(), np.uint8, offset=16).reshape(len(y_train), 28, 28)

  with gzip.open(paths[2], 'rb') as lbpath:
    y_test = np.frombuffer(lbpath.read(), np.uint8, offset=8)

  with gzip.open(paths[3], 'rb') as imgpath:
    x_test = np.frombuffer(
        imgpath.read(), np.uint8, offset=16).reshape(len(y_test), 28, 28)

  return (x_train, y_train), (x_test, y_test)
Exemple #7
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def load_data(label_mode='fine'):
  """Loads CIFAR100 dataset.

  Arguments:
      label_mode: one of "fine", "coarse".

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case of invalid `label_mode`.
  """
  if label_mode not in ['fine', 'coarse']:
    raise ValueError('label_mode must be one of "fine" "coarse".')

  dirname = 'cifar-100-python'
  origin = 'http://www.cs.toronto.edu/~kriz/cifar-100-python.tar.gz'
  path = get_file(dirname, origin=origin, untar=True)

  fpath = os.path.join(path, 'train')
  x_train, y_train = load_batch(fpath, label_key=label_mode + '_labels')

  fpath = os.path.join(path, 'test')
  x_test, y_test = load_batch(fpath, label_key=label_mode + '_labels')

  y_train = np.reshape(y_train, (len(y_train), 1))
  y_test = np.reshape(y_test, (len(y_test), 1))

  if K.image_data_format() == 'channels_last':
    x_train = x_train.transpose(0, 2, 3, 1)
    x_test = x_test.transpose(0, 2, 3, 1)

  return (x_train, y_train), (x_test, y_test)
Exemple #8
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def load_data():
    """Loads the Fashion-MNIST dataset.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
    dirname = os.path.join('datasets', 'fashion-mnist')
    base = 'http://fashion-mnist.s3-website.eu-central-1.amazonaws.com/'
    files = [
        'train-labels-idx1-ubyte.gz', 'train-images-idx3-ubyte.gz',
        't10k-labels-idx1-ubyte.gz', 't10k-images-idx3-ubyte.gz'
    ]

    paths = []
    for given_file in files:
        paths.append(
            get_file(given_file,
                     origin=base + given_file,
                     cache_subdir=dirname))

    with gzip.open(paths[0], 'rb') as lbpath:
        y_train = np.frombuffer(lbpath.read(), np.uint8, offset=8)

    with gzip.open(paths[1], 'rb') as imgpath:
        x_train = np.frombuffer(imgpath.read(), np.uint8,
                                offset=16).reshape(len(y_train), 28, 28)

    with gzip.open(paths[2], 'rb') as lbpath:
        y_test = np.frombuffer(lbpath.read(), np.uint8, offset=8)

    with gzip.open(paths[3], 'rb') as imgpath:
        x_test = np.frombuffer(imgpath.read(), np.uint8,
                               offset=16).reshape(len(y_test), 28, 28)

    return (x_train, y_train), (x_test, y_test)
def load_data(path='boston_housing.npz', seed=113, test_split=0.2):
  """Loads the Boston Housing dataset.

  Arguments:
      path: path where to cache the dataset locally
          (relative to ~/.keras/datasets).
      seed: Random seed for shuffling the data
          before computing the test split.
      test_split: fraction of the data to reserve as test set.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
  assert 0 <= test_split < 1
  fh = 'f553886a1f8d56431e820c5b82552d9d95cfcb96d1e678153f8839538947dff5'
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/keras-datasets/boston_housing.npz',
      file_hash=fh)
  f = np.load(path)
  x = f['x']
  y = f['y']
  f.close()

  np.random.seed(seed)
  indices = np.arange(len(x))
  np.random.shuffle(indices)
  x = x[indices]
  y = y[indices]

  x_train = np.array(x[:int(len(x) * (1 - test_split))])
  y_train = np.array(y[:int(len(x) * (1 - test_split))])
  x_test = np.array(x[int(len(x) * (1 - test_split)):])
  y_test = np.array(y[int(len(x) * (1 - test_split)):])
  return (x_train, y_train), (x_test, y_test)
Exemple #10
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def load_data():
    """Loads CIFAR10 dataset.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
    dirname = 'cifar-10-batches-py'
    origin = 'https://www.cs.toronto.edu/~kriz/cifar-10-python.tar.gz'
    path = get_file(dirname, origin=origin, untar=True)

    num_train_samples = 50000

    x_train = np.empty((num_train_samples, 3, 32, 32), dtype='uint8')
    y_train = np.empty((num_train_samples, ), dtype='uint8')

    for i in range(1, 6):
        fpath = os.path.join(path, 'data_batch_' + str(i))
        (x_train[(i - 1) * 10000:i * 10000, :, :, :],
         y_train[(i - 1) * 10000:i * 10000]) = load_batch(fpath)

    fpath = os.path.join(path, 'test_batch')
    x_test, y_test = load_batch(fpath)

    y_train = np.reshape(y_train, (len(y_train), 1))
    y_test = np.reshape(y_test, (len(y_test), 1))

    if K.image_data_format() == 'channels_last':
        x_train = x_train.transpose(0, 2, 3, 1)
        x_test = x_test.transpose(0, 2, 3, 1)

    return (x_train, y_train), (x_test, y_test)
Exemple #11
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def decode_predictions(preds, top=5):
  """Decodes the prediction of an ImageNet model.

  Arguments:
      preds: Numpy tensor encoding a batch of predictions.
      top: integer, how many top-guesses to return.

  Returns:
      A list of lists of top class prediction tuples
      `(class_name, class_description, score)`.
      One list of tuples per sample in batch input.

  Raises:
      ValueError: in case of invalid shape of the `pred` array
          (must be 2D).
  """
  global CLASS_INDEX
  if len(preds.shape) != 2 or preds.shape[1] != 1000:
    raise ValueError('`decode_predictions` expects '
                     'a batch of predictions '
                     '(i.e. a 2D array of shape (samples, 1000)). '
                     'Found array with shape: ' + str(preds.shape))
  if CLASS_INDEX is None:
    fpath = get_file('imagenet_class_index.json',
                     CLASS_INDEX_PATH,
                     cache_subdir='models',
                     file_hash='c2c37ea517e94d9795004a39431a14cb')
    CLASS_INDEX = json.load(open(fpath))
  results = []
  for pred in preds:
    top_indices = pred.argsort()[-top:][::-1]
    result = [tuple(CLASS_INDEX[str(i)]) + (pred[i],) for i in top_indices]
    result.sort(key=lambda x: x[2], reverse=True)
    results.append(result)
  return results
def load_cifar100_data(label_mode='fine'):
    """loads cifar100 dataset.
  arguments:
      label_mode: one of "fine", "coarse".
  returns:
      tuple of numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  raises:
      valueerror: in case of invalid `label_mode`.
  """
    if label_mode not in ['fine', 'coarse']:
        raise valueerror('label_mode must be one of "fine" "coarse".')
    print('load cifar100 dataset')
    dirname = 'cifar-100-python'
    origin = 'https://www.cs.toronto.edu/~kriz/cifar-100-python.tar.gz'
    path = get_file(dirname, origin=origin, untar=True)

    fpath = os.path.join(path, 'train')
    x_train, y_train = load_batch(fpath, label_key=label_mode + '_labels')

    fpath = os.path.join(path, 'test')
    x_test, y_test = load_batch(fpath, label_key=label_mode + '_labels')

    y_train = np.reshape(y_train, (len(y_train), 1))
    y_test = np.reshape(y_test, (len(y_test), 1))

    if K.image_data_format() == 'channels_last':
        x_train = x_train.transpose(0, 2, 3, 1)
        x_test = x_test.transpose(0, 2, 3, 1)

    y_test = map(one_hot_vec_100, y_test)
    y_train = map(one_hot_vec_100, y_train)
    return (x_train, y_train, x_test, y_test)
Exemple #13
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 def get_word_index(self, path = 'imdb_word_index.json'):
     logging.info('Load the dictionaries...')
     path = get_file(path, origin = 'https://s3.amazonaws.com/text-datasets/imdb_word_index.json')
     f = open(path)
     data = json.load(f)
     f.close()
     logging.info('Load the dictionaries, size : %d' % len(data))
     return data
Exemple #14
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 def get_word_index(self, path = 'imdb_word_index.json'):
     logging.info('Load the dictionaries...')
     path = os.path.join(os.getcwd(), self.args.tmp_dir, self.__class__.__name__, 'imdb_word_index.json')
     path = get_file(path, origin = 'https://s3.amazonaws.com/text-datasets/imdb_word_index.json')
     f = open(path)
     data = json.load(f)
     data = {k: v + 2 for k, v in data.items()}
     data.setdefault('_<PAD>', 0)
     data.setdefault('_<UNKNOW>', 1)
     f.close()
     logging.info('Load the dictionaries, size : %d' % len(data))
     return data, path
def get_word_index(path='imdb_word_index.json'):
    """Retrieves the dictionary mapping word indices back to words.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).

  Returns:
      The word index dictionary.
  """
    path = get_file(
        path,
        origin='https://s3.amazonaws.com/text-datasets/imdb_word_index.json',
        file_hash='bfafd718b763782e994055a2d397834f')
    with open(path) as f:
        return json.load(f)
Exemple #16
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def get_word_index(path='imdb_word_index.json'):
  """Retrieves the dictionary mapping word indices back to words.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).

  Returns:
      The word index dictionary.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/imdb_word_index.json',
      file_hash='bfafd718b763782e994055a2d397834f')
  with open(path) as f:
    return json.load(f)
def get_word_index(path='imdb_word_index.json'):
    """Retrieves the dictionary mapping word indices back to words.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).

  Returns:
      The word index dictionary.
  """
    path = get_file(
        path,
        origin='https://s3.amazonaws.com/text-datasets/imdb_word_index.json')
    f = open(path)
    data = json.load(f)
    f.close()
    return data
Exemple #18
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def get_word_index(path='imdb_word_index.json'):
  """Retrieves the dictionary mapping word indices back to words.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).

  Returns:
      The word index dictionary.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/imdb_word_index.json')
  f = open(path)
  data = json.load(f)
  f.close()
  return data
Exemple #19
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def get_word_index(path='reuters_word_index.json'):
  """Retrieves the dictionary mapping word indices back to words.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).

  Returns:
      The word index dictionary.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/reuters_word_index.json',
      file_hash='4d44cc38712099c9e383dc6e5f11a921')
  f = open(path)
  data = json.load(f)
  f.close()
  return data
Exemple #20
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def load_data(path='mnist.npz'):
    """Loads the MNIST dataset.

  Arguments:
      path: path where to cache the dataset locally
          (relative to ~/.keras/datasets).

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
    path = get_file(path,
                    origin='https://s3.amazonaws.com/img-datasets/mnist.npz',
                    file_hash='8a61469f7ea1b51cbae51d4f78837e45')
    f = np.load(path)
    x_train, y_train = f['x_train'], f['y_train']
    x_test, y_test = f['x_test'], f['y_test']
    f.close()
    return (x_train, y_train), (x_test, y_test)
Exemple #21
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def load_data(path='mnist.npz'):
  """Loads the MNIST dataset.

  Arguments:
      path: path where to cache the dataset locally
          (relative to ~/.keras/datasets).

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/img-datasets/mnist.npz',
      file_hash='8a61469f7ea1b51cbae51d4f78837e45')
  f = np.load(path)
  x_train, y_train = f['x_train'], f['y_train']
  x_test, y_test = f['x_test'], f['y_test']
  f.close()
  return (x_train, y_train), (x_test, y_test)
Exemple #22
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def readCifar10Keras():

   
    import numpy as np
    from tensorflow.python.keras._impl.keras.datasets.cifar10 import load_data
    from tensorflow.python.keras._impl.keras.utils.data_utils import get_file

    dirname = 'cifar-10-batches-py'
    origin = 'https://www.cs.toronto.edu/~kriz/cifar-10-python.tar.gz'
    path = get_file(dirname, origin=origin, untar=True)
    print(path)
    (x_train, y_train), (x_test, y_test) = load_data()
    
    fig ,ax=  plt.subplots(10, 10, figsize=(10, 10))     
    index =0
    for i in  range(10) :
        for j in range(10):
            ax[i][j].imshow(x_train[index]) 
            ax[i][j].annotate(str(y_train[index]) + str(i) + "," + str(j), xy=(0, 0), xytext=(0, -1), arrowprops=None, fontsize=8)
            index+=1
         
    plt.show()
Exemple #23
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def VGG19(include_top=True,
          weights='imagenet',
          input_tensor=None,
          input_shape=None,
          pooling=None,
          classes=1000):
  """Instantiates the VGG19 architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.

  The model and the weights are compatible with both
  TensorFlow and Theano. The data format
  convention used by the model is the one
  specified in your Keras config file.

  Arguments:
      include_top: whether to include the 3 fully-connected
          layers at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or `(3, 224, 224)` (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 48.
          E.g. `(200, 200, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')
  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=224,
      min_size=48,
      data_format=K.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor
  # Block 1
  x = Conv2D(
      64, (3, 3), activation='relu', padding='same', name='block1_conv1')(
          img_input)
  x = Conv2D(
      64, (3, 3), activation='relu', padding='same', name='block1_conv2')(
          x)
  x = MaxPooling2D((2, 2), strides=(2, 2), name='block1_pool')(x)

  # Block 2
  x = Conv2D(
      128, (3, 3), activation='relu', padding='same', name='block2_conv1')(
          x)
  x = Conv2D(
      128, (3, 3), activation='relu', padding='same', name='block2_conv2')(
          x)
  x = MaxPooling2D((2, 2), strides=(2, 2), name='block2_pool')(x)

  # Block 3
  x = Conv2D(
      256, (3, 3), activation='relu', padding='same', name='block3_conv1')(
          x)
  x = Conv2D(
      256, (3, 3), activation='relu', padding='same', name='block3_conv2')(
          x)
  x = Conv2D(
      256, (3, 3), activation='relu', padding='same', name='block3_conv3')(
          x)
  x = Conv2D(
      256, (3, 3), activation='relu', padding='same', name='block3_conv4')(
          x)
  x = MaxPooling2D((2, 2), strides=(2, 2), name='block3_pool')(x)

  # Block 4
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block4_conv1')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block4_conv2')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block4_conv3')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block4_conv4')(
          x)
  x = MaxPooling2D((2, 2), strides=(2, 2), name='block4_pool')(x)

  # Block 5
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block5_conv1')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block5_conv2')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block5_conv3')(
          x)
  x = Conv2D(
      512, (3, 3), activation='relu', padding='same', name='block5_conv4')(
          x)
  x = MaxPooling2D((2, 2), strides=(2, 2), name='block5_pool')(x)

  if include_top:
    # Classification block
    x = Flatten(name='flatten')(x)
    x = Dense(4096, activation='relu', name='fc1')(x)
    x = Dense(4096, activation='relu', name='fc2')(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input
  # Create model.
  model = Model(inputs, x, name='vgg19')

  # load weights
  if weights == 'imagenet':
    if include_top:
      weights_path = get_file(
          'vgg19_weights_tf_dim_ordering_tf_kernels.h5',
          WEIGHTS_PATH,
          cache_subdir='models',
          file_hash='cbe5617147190e668d6c5d5026f83318')
    else:
      weights_path = get_file(
          'vgg19_weights_tf_dim_ordering_tf_kernels_notop.h5',
          WEIGHTS_PATH_NO_TOP,
          cache_subdir='models',
          file_hash='253f8cb515780f3b799900260a226db6')
    model.load_weights(weights_path)
    if K.backend() == 'theano':
      layer_utils.convert_all_kernels_in_model(model)

    if K.image_data_format() == 'channels_first':
      if include_top:
        maxpool = model.get_layer(name='block5_pool')
        shape = maxpool.output_shape[1:]
        dense = model.get_layer(name='fc1')
        layer_utils.convert_dense_weights_data_format(dense, shape,
                                                      'channels_first')

  elif weights is not None:
    model.load_weights(weights)

  return model
Exemple #24
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def ResNet50(include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
    """Instantiates the ResNet50 architecture.

    Optionally loads weights pre-trained
    on ImageNet. Note that when using TensorFlow,
    for best performance you should set
    `image_data_format='channels_last'` in your Keras config
    at ~/.keras/keras.json.

    The model and the weights are compatible with both
    TensorFlow and Theano. The data format
    convention used by the model is the one
    specified in your Keras config file.

    # Arguments
        include_top: whether to include the fully-connected
            layer at the top of the network.
        weights: one of `None` (random initialization)
            or 'imagenet' (pre-training on ImageNet).
        input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
            to use as image input for the model.
        input_shape: optional shape tuple, only to be specified
            if `include_top` is False (otherwise the input shape
            has to be `(224, 224, 3)` (with `channels_last` data format)
            or `(3, 224, 224)` (with `channels_first` data format).
            It should have exactly 3 inputs channels,
            and width and height should be no smaller than 197.
            E.g. `(200, 200, 3)` would be one valid value.
        pooling: Optional pooling mode for feature extraction
            when `include_top` is `False`.
            - `None` means that the output of the model will be
                the 4D tensor output of the
                last convolutional layer.
            - `avg` means that global average pooling
                will be applied to the output of the
                last convolutional layer, and thus
                the output of the model will be a 2D tensor.
            - `max` means that global max pooling will
                be applied.
        classes: optional number of classes to classify images
            into, only to be specified if `include_top` is True, and
            if no `weights` argument is specified.

    # Returns
        A Keras model instance.

    # Raises
        ValueError: in case of invalid argument for `weights`,
            or invalid input shape.
    """
    if weights not in {'imagenet', None}:
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization) or `imagenet` '
                         '(pre-training on ImageNet).')

    if weights == 'imagenet' and include_top and classes != 1000:
        raise ValueError('If using `weights` as imagenet with `include_top`'
                         ' as true, `classes` should be 1000')

    # Determine proper input shape
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=48,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor
    if K.image_data_format() == 'channels_last':
        bn_axis = 3
    else:
        bn_axis = 1

    x = Conv2D(
        #64, (7, 7), strides=(2, 2), padding='same', name='conv1')(img_input)
        64,
        (7, 7),
        strides=(1, 1),
        padding='same',
        name='conv1')(img_input)
    x = BatchNormalization(axis=bn_axis, name='bn_conv1')(x)
    x = Activation('relu')(x)
    x = MaxPooling2D((3, 3), strides=(2, 2))(x)

    x = conv_block(x, 3, [64, 64, 256], stage=2, block='a', strides=(1, 1))
    x = identity_block(x, 3, [64, 64, 256], stage=2, block='b')
    x = identity_block(x, 3, [64, 64, 256], stage=2, block='c')

    x = conv_block(x, 3, [128, 128, 512], stage=3, block='a')
    x = identity_block(x, 3, [128, 128, 512], stage=3, block='b')
    x = identity_block(x, 3, [128, 128, 512], stage=3, block='c')
    x = identity_block(x, 3, [128, 128, 512], stage=3, block='d')

    x = conv_block(x, 3, [256, 256, 1024], stage=4, block='a')
    x = identity_block(x, 3, [256, 256, 1024], stage=4, block='b')
    x = identity_block(x, 3, [256, 256, 1024], stage=4, block='c')
    x = identity_block(x, 3, [256, 256, 1024], stage=4, block='d')
    x = identity_block(x, 3, [256, 256, 1024], stage=4, block='e')
    x = identity_block(x, 3, [256, 256, 1024], stage=4, block='f')

    x = conv_block(x, 3, [512, 512, 2048], stage=5, block='a')
    x = identity_block(x, 3, [512, 512, 2048], stage=5, block='b')
    x = identity_block(x, 3, [512, 512, 2048], stage=5, block='c')

    #x = AveragePooling2D((7, 7), name='avg_pool')(x)
    #x = AveragePooling2D((2, 2), name='avg_pool')(x)
    x = AveragePooling2D((4, 4), name='avg_pool')(x)

    if include_top:
        x = Flatten()(x)
        x = Dense(classes, activation='softmax', name='fc1000')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input
    # Create model.
    model = Model(inputs, x, name='resnet50')

    # load weights
    if weights == 'imagenet':
        if include_top:
            weights_path = get_file(
                'resnet50_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models',
                md5_hash='a7b3fe01876f51b976af0dea6bc144eb')
        else:
            weights_path = get_file(
                'resnet50_weights_tf_dim_ordering_tf_kernels_notop.h5',
                WEIGHTS_PATH_NO_TOP,
                cache_subdir='models',
                md5_hash='a268eb855778b3df3c7506639542a6af')
        model.load_weights(weights_path)
        if K.backend() == 'theano':
            layer_utils.convert_all_kernels_in_model(model)
            if include_top:
                maxpool = model.get_layer(name='avg_pool')
                shape = maxpool.output_shape[1:]
                dense = model.get_layer(name='fc1000')
                layer_utils.convert_dense_weights_data_format(
                    dense, shape, 'channels_first')

        if K.image_data_format() == 'channels_first' and K.backend(
        ) == 'tensorflow':
            warnings.warn('You are using the TensorFlow backend, yet you '
                          'are using the Theano '
                          'image data format convention '
                          '(`image_data_format="channels_first"`). '
                          'For best performance, set '
                          '`image_data_format="channels_last"` in '
                          'your Keras config '
                          'at ~/.keras/keras.json.')
    return model
Exemple #25
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def Xception(include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
    """Instantiates the Xception architecture.

  Optionally loads weights pre-trained
  on ImageNet. This model is available for TensorFlow only,
  and can only be used with inputs following the TensorFlow
  data format `(width, height, channels)`.
  You should set `image_data_format='channels_last'` in your Keras config
  located at ~/.keras/keras.json.

  Note that the default input image size for this model is 299x299.

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(299, 299, 3)`.
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 71.
          E.g. `(150, 150, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
      RuntimeError: If attempting to run this model with a
          backend that does not support separable convolutions.
  """
    if not (weights in {'imagenet', None} or os.path.exists(weights)):
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization), `imagenet` '
                         '(pre-training on ImageNet), '
                         'or the path to the weights file to be loaded.')

    if weights == 'imagenet' and include_top and classes != 1000:
        raise ValueError('If using `weights` as imagenet with `include_top`'
                         ' as true, `classes` should be 1000')

    if K.image_data_format() != 'channels_last':
        logging.warning(
            'The Xception model is only available for the '
            'input data format "channels_last" '
            '(width, height, channels). '
            'However your settings specify the default '
            'data format "channels_first" (channels, width, height). '
            'You should set `image_data_format="channels_last"` in your Keras '
            'config located at ~/.keras/keras.json. '
            'The model being returned right now will expect inputs '
            'to follow the "channels_last" data format.')
        K.set_image_data_format('channels_last')
        old_data_format = 'channels_first'
    else:
        old_data_format = None

    # Determine proper input shape
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=299,
                                      min_size=71,
                                      data_format=K.image_data_format(),
                                      require_flatten=False,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

    x = Conv2D(32, (3, 3), strides=(2, 2), use_bias=False,
               name='block1_conv1')(img_input)
    x = BatchNormalization(name='block1_conv1_bn')(x)
    x = Activation('relu', name='block1_conv1_act')(x)
    x = Conv2D(64, (3, 3), use_bias=False, name='block1_conv2')(x)
    x = BatchNormalization(name='block1_conv2_bn')(x)
    x = Activation('relu', name='block1_conv2_act')(x)

    residual = Conv2D(128, (1, 1),
                      strides=(2, 2),
                      padding='same',
                      use_bias=False)(x)
    residual = BatchNormalization()(residual)

    x = SeparableConv2D(128, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block2_sepconv1')(x)
    x = BatchNormalization(name='block2_sepconv1_bn')(x)
    x = Activation('relu', name='block2_sepconv2_act')(x)
    x = SeparableConv2D(128, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block2_sepconv2')(x)
    x = BatchNormalization(name='block2_sepconv2_bn')(x)

    x = MaxPooling2D((3, 3),
                     strides=(2, 2),
                     padding='same',
                     name='block2_pool')(x)
    x = layers.add([x, residual])

    residual = Conv2D(256, (1, 1),
                      strides=(2, 2),
                      padding='same',
                      use_bias=False)(x)
    residual = BatchNormalization()(residual)

    x = Activation('relu', name='block3_sepconv1_act')(x)
    x = SeparableConv2D(256, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block3_sepconv1')(x)
    x = BatchNormalization(name='block3_sepconv1_bn')(x)
    x = Activation('relu', name='block3_sepconv2_act')(x)
    x = SeparableConv2D(256, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block3_sepconv2')(x)
    x = BatchNormalization(name='block3_sepconv2_bn')(x)

    x = MaxPooling2D((3, 3),
                     strides=(2, 2),
                     padding='same',
                     name='block3_pool')(x)
    x = layers.add([x, residual])

    residual = Conv2D(728, (1, 1),
                      strides=(2, 2),
                      padding='same',
                      use_bias=False)(x)
    residual = BatchNormalization()(residual)

    x = Activation('relu', name='block4_sepconv1_act')(x)
    x = SeparableConv2D(728, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block4_sepconv1')(x)
    x = BatchNormalization(name='block4_sepconv1_bn')(x)
    x = Activation('relu', name='block4_sepconv2_act')(x)
    x = SeparableConv2D(728, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block4_sepconv2')(x)
    x = BatchNormalization(name='block4_sepconv2_bn')(x)

    x = MaxPooling2D((3, 3),
                     strides=(2, 2),
                     padding='same',
                     name='block4_pool')(x)
    x = layers.add([x, residual])

    for i in range(8):
        residual = x
        prefix = 'block' + str(i + 5)

        x = Activation('relu', name=prefix + '_sepconv1_act')(x)
        x = SeparableConv2D(728, (3, 3),
                            padding='same',
                            use_bias=False,
                            name=prefix + '_sepconv1')(x)
        x = BatchNormalization(name=prefix + '_sepconv1_bn')(x)
        x = Activation('relu', name=prefix + '_sepconv2_act')(x)
        x = SeparableConv2D(728, (3, 3),
                            padding='same',
                            use_bias=False,
                            name=prefix + '_sepconv2')(x)
        x = BatchNormalization(name=prefix + '_sepconv2_bn')(x)
        x = Activation('relu', name=prefix + '_sepconv3_act')(x)
        x = SeparableConv2D(728, (3, 3),
                            padding='same',
                            use_bias=False,
                            name=prefix + '_sepconv3')(x)
        x = BatchNormalization(name=prefix + '_sepconv3_bn')(x)

        x = layers.add([x, residual])

    residual = Conv2D(1024, (1, 1),
                      strides=(2, 2),
                      padding='same',
                      use_bias=False)(x)
    residual = BatchNormalization()(residual)

    x = Activation('relu', name='block13_sepconv1_act')(x)
    x = SeparableConv2D(728, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block13_sepconv1')(x)
    x = BatchNormalization(name='block13_sepconv1_bn')(x)
    x = Activation('relu', name='block13_sepconv2_act')(x)
    x = SeparableConv2D(1024, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block13_sepconv2')(x)
    x = BatchNormalization(name='block13_sepconv2_bn')(x)

    x = MaxPooling2D((3, 3),
                     strides=(2, 2),
                     padding='same',
                     name='block13_pool')(x)
    x = layers.add([x, residual])

    x = SeparableConv2D(1536, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block14_sepconv1')(x)
    x = BatchNormalization(name='block14_sepconv1_bn')(x)
    x = Activation('relu', name='block14_sepconv1_act')(x)

    x = SeparableConv2D(2048, (3, 3),
                        padding='same',
                        use_bias=False,
                        name='block14_sepconv2')(x)
    x = BatchNormalization(name='block14_sepconv2_bn')(x)
    x = Activation('relu', name='block14_sepconv2_act')(x)

    if include_top:
        x = GlobalAveragePooling2D(name='avg_pool')(x)
        x = Dense(classes, activation='softmax', name='predictions')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input
    # Create model.
    model = Model(inputs, x, name='xception')

    # load weights
    if weights == 'imagenet':
        if include_top:
            weights_path = get_file(
                'xception_weights_tf_dim_ordering_tf_kernels.h5',
                TF_WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='0a58e3b7378bc2990ea3b43d5981f1f6')
        else:
            weights_path = get_file(
                'xception_weights_tf_dim_ordering_tf_kernels_notop.h5',
                TF_WEIGHTS_PATH_NO_TOP,
                cache_subdir='models',
                file_hash='b0042744bf5b25fce3cb969f33bebb97')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    if old_data_format:
        K.set_image_data_format(old_data_format)
    return model
def InceptionV3(include_top=True,
                weights='imagenet',
                input_tensor=None,
                input_shape=None,
                pooling=None,
                classes=1000):
  """Instantiates the Inception v3 architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.
  The model and the weights are compatible with both
  TensorFlow and Theano. The data format
  convention used by the model is the one
  specified in your Keras config file.
  Note that the default input image size for this model is 299x299.

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(299, 299, 3)` (with `channels_last` data format)
          or `(3, 299, 299)` (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 139.
          E.g. `(150, 150, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=299,
      min_size=139,
      data_format=K.image_data_format(),
      require_flatten=False,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor

  if K.image_data_format() == 'channels_first':
    channel_axis = 1
  else:
    channel_axis = 3

  x = conv2d_bn(img_input, 32, 3, 3, strides=(2, 2), padding='valid')
  x = conv2d_bn(x, 32, 3, 3, padding='valid')
  x = conv2d_bn(x, 64, 3, 3)
  x = MaxPooling2D((3, 3), strides=(2, 2))(x)

  x = conv2d_bn(x, 80, 1, 1, padding='valid')
  x = conv2d_bn(x, 192, 3, 3, padding='valid')
  x = MaxPooling2D((3, 3), strides=(2, 2))(x)

  # mixed 0, 1, 2: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 32, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed0')

  # mixed 1: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 64, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed1')

  # mixed 2: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 64, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed2')

  # mixed 3: 17 x 17 x 768
  branch3x3 = conv2d_bn(x, 384, 3, 3, strides=(2, 2), padding='valid')

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(
      branch3x3dbl, 96, 3, 3, strides=(2, 2), padding='valid')

  branch_pool = MaxPooling2D((3, 3), strides=(2, 2))(x)
  x = layers.concatenate(
      [branch3x3, branch3x3dbl, branch_pool], axis=channel_axis, name='mixed3')

  # mixed 4: 17 x 17 x 768
  branch1x1 = conv2d_bn(x, 192, 1, 1)

  branch7x7 = conv2d_bn(x, 128, 1, 1)
  branch7x7 = conv2d_bn(branch7x7, 128, 1, 7)
  branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

  branch7x7dbl = conv2d_bn(x, 128, 1, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 1, 7)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch7x7, branch7x7dbl, branch_pool],
      axis=channel_axis,
      name='mixed4')

  # mixed 5, 6: 17 x 17 x 768
  for i in range(2):
    branch1x1 = conv2d_bn(x, 192, 1, 1)

    branch7x7 = conv2d_bn(x, 160, 1, 1)
    branch7x7 = conv2d_bn(branch7x7, 160, 1, 7)
    branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

    branch7x7dbl = conv2d_bn(x, 160, 1, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 7, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 1, 7)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 7, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

    branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
    branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
    x = layers.concatenate(
        [branch1x1, branch7x7, branch7x7dbl, branch_pool],
        axis=channel_axis,
        name='mixed' + str(5 + i))

  # mixed 7: 17 x 17 x 768
  branch1x1 = conv2d_bn(x, 192, 1, 1)

  branch7x7 = conv2d_bn(x, 192, 1, 1)
  branch7x7 = conv2d_bn(branch7x7, 192, 1, 7)
  branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

  branch7x7dbl = conv2d_bn(x, 192, 1, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch7x7, branch7x7dbl, branch_pool],
      axis=channel_axis,
      name='mixed7')

  # mixed 8: 8 x 8 x 1280
  branch3x3 = conv2d_bn(x, 192, 1, 1)
  branch3x3 = conv2d_bn(branch3x3, 320, 3, 3, strides=(2, 2), padding='valid')

  branch7x7x3 = conv2d_bn(x, 192, 1, 1)
  branch7x7x3 = conv2d_bn(branch7x7x3, 192, 1, 7)
  branch7x7x3 = conv2d_bn(branch7x7x3, 192, 7, 1)
  branch7x7x3 = conv2d_bn(
      branch7x7x3, 192, 3, 3, strides=(2, 2), padding='valid')

  branch_pool = MaxPooling2D((3, 3), strides=(2, 2))(x)
  x = layers.concatenate(
      [branch3x3, branch7x7x3, branch_pool], axis=channel_axis, name='mixed8')

  # mixed 9: 8 x 8 x 2048
  for i in range(2):
    branch1x1 = conv2d_bn(x, 320, 1, 1)

    branch3x3 = conv2d_bn(x, 384, 1, 1)
    branch3x3_1 = conv2d_bn(branch3x3, 384, 1, 3)
    branch3x3_2 = conv2d_bn(branch3x3, 384, 3, 1)
    branch3x3 = layers.concatenate(
        [branch3x3_1, branch3x3_2], axis=channel_axis, name='mixed9_' + str(i))

    branch3x3dbl = conv2d_bn(x, 448, 1, 1)
    branch3x3dbl = conv2d_bn(branch3x3dbl, 384, 3, 3)
    branch3x3dbl_1 = conv2d_bn(branch3x3dbl, 384, 1, 3)
    branch3x3dbl_2 = conv2d_bn(branch3x3dbl, 384, 3, 1)
    branch3x3dbl = layers.concatenate(
        [branch3x3dbl_1, branch3x3dbl_2], axis=channel_axis)

    branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
    branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
    x = layers.concatenate(
        [branch1x1, branch3x3, branch3x3dbl, branch_pool],
        axis=channel_axis,
        name='mixed' + str(9 + i))
  if include_top:
    # Classification block
    x = GlobalAveragePooling2D(name='avg_pool')(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input
  # Create model.
  model = Model(inputs, x, name='inception_v3')

  # load weights
  if weights == 'imagenet':
    if include_top:
      weights_path = get_file(
          'inception_v3_weights_tf_dim_ordering_tf_kernels.h5',
          WEIGHTS_PATH,
          cache_subdir='models',
          file_hash='9a0d58056eeedaa3f26cb7ebd46da564')
    else:
      weights_path = get_file(
          'inception_v3_weights_tf_dim_ordering_tf_kernels_notop.h5',
          WEIGHTS_PATH_NO_TOP,
          cache_subdir='models',
          file_hash='bcbd6486424b2319ff4ef7d526e38f63')
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)

  return model
Exemple #27
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def load_data(path='imdb.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3):
  """Loads the IMDB dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: sequences longer than this will be filtered out.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case `maxlen` is so low
          that no input sequence could be kept.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/imdb.npz',
      file_hash='599dadb1135973df5b59232a0e9a887c')
  f = np.load(path)
  x_train, labels_train = f['x_train'], f['y_train']
  x_test, labels_test = f['x_test'], f['y_test']
  f.close()

  np.random.seed(seed)
  indices = np.arrange(len(x_train))
  np.random.shuffle(indices)
  x_train = x_train[indices]
  labels_train = labels_train[indices]

  indices = np.arrange(len(x_test))
  np.random.shuffle(indices)
  x_test = x_test[indices]
  labels_test = labels_test[indices]

  xs = np.concatenate([x_train, x_test])
  labels = np.concatenate([labels_train, labels_test])

  if start_char is not None:
    xs = [[start_char] + [w + index_from for w in x] for x in xs]
  elif index_from:
    xs = [[w + index_from for w in x] for x in xs]

  if maxlen:
    new_xs = []
    new_labels = []
    for x, y in zip(xs, labels):
      if len(x) < maxlen:
        new_xs.append(x)
        new_labels.append(y)
    xs = new_xs
    labels = new_labels
    if not xs:
      raise ValueError('After filtering for sequences shorter than maxlen=' +
                       str(maxlen) + ', no sequence was kept. '
                       'Increase maxlen.')
  if not num_words:
    num_words = max([max(x) for x in xs])

  # by convention, use 2 as OOV word
  # reserve 'index_from' (=3 by default) characters:
  # 0 (padding), 1 (start), 2 (OOV)
  if oov_char is not None:
    xs = [[oov_char if (w >= num_words or w < skip_top) else w for w in x]
          for x in xs]
  else:
    new_xs = []
    for x in xs:
      nx = []
      for w in x:
        if skip_top <= w < num_words:
          nx.append(w)
      new_xs.append(nx)
    xs = new_xs

  x_train = np.array(xs[:len(x_train)])
  y_train = np.array(labels[:len(x_train)])

  x_test = np.array(xs[len(x_train):])
  y_test = np.array(labels[len(x_train):])

  return (x_train, y_train), (x_test, y_test)
Exemple #28
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def VGG16(include_top=True, weights='vggface',
          input_tensor=None, input_shape=None,
          pooling=None,
          classes=2622):
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=48,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

    # Block 1
    x = Conv2D(64, (3, 3), activation='relu', padding='same', name='conv1_1')(
        img_input)
    x = Conv2D(64, (3, 3), activation='relu', padding='same', name='conv1_2')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='pool1')(x)

    # Block 2
    x = Conv2D(128, (3, 3), activation='relu', padding='same', name='conv2_1')(
        x)
    x = Conv2D(128, (3, 3), activation='relu', padding='same', name='conv2_2')(
        x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='pool2')(x)

    # Block 3
    x = Conv2D(256, (3, 3), activation='relu', padding='same', name='conv3_1')(
        x)
    x = Conv2D(256, (3, 3), activation='relu', padding='same', name='conv3_2')(
        x)
    x = Conv2D(256, (3, 3), activation='relu', padding='same', name='conv3_3')(
        x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='pool3')(x)

    # Block 4
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv4_1')(
        x)
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv4_2')(
        x)
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv4_3')(
        x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='pool4')(x)

    # Block 5
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv5_1')(
        x)
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv5_2')(
        x)
    x = Conv2D(512, (3, 3), activation='relu', padding='same', name='conv5_3')(
        x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='pool5')(x)

    if include_top:
        # Classification block
        x = Flatten(name='flatten')(x)
        x = Dense(4096, name='fc6')(x)
        x = Activation('relu', name='fc6/relu')(x)
        x = Dense(4096, name='fc7')(x)
        x = Activation('relu', name='fc7/relu')(x)
        x = Dense(classes, name='fc8')(x)
        x = Activation('softmax', name='fc8/softmax')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

            # Ensure that the model takes into account
            # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input
        # Create model.
    model = Model(inputs, x, name='vggface_vgg16')  # load weights
    if weights == 'vggface':
        if include_top:
            weights_path = get_file('rcmalli_vggface_tf_vgg16.h5',
                                    utils.
                                    VGG16_WEIGHTS_PATH,
                                    cache_subdir=utils.VGGFACE_DIR)
        else:
            weights_path = get_file('rcmalli_vggface_tf_notop_vgg16.h5',
                                    utils.VGG16_WEIGHTS_PATH_NO_TOP,
                                    cache_subdir=utils.VGGFACE_DIR)
        model.load_weights(weights_path, by_name=True)
        if K.backend() == 'theano':
            layer_utils.convert_all_kernels_in_model(model)

        if K.image_data_format() == 'channels_first':
            if include_top:
                maxpool = model.get_layer(name='pool5')
                shape = maxpool.output_shape[1:]
                dense = model.get_layer(name='fc6')
                layer_utils.convert_dense_weights_data_format(dense, shape,
                                                              'channels_first')

            if K.backend() == 'tensorflow':
                warnings.warn('You are using the TensorFlow backend, yet you '
                              'are using the Theano '
                              'image data format convention '
                              '(`image_data_format="channels_first"`). '
                              'For best performance, set '
                              '`image_data_format="channels_last"` in '
                              'your Keras config '
                              'at ~/.keras/keras.json.')
    return model
def MobileNet(input_shape=None,
              alpha=1.0,
              depth_multiplier=1,
              dropout=1e-3,
              include_top=True,
              weights='imagenet',
              input_tensor=None,
              pooling=None,
              classes=1000):
  """Instantiates the MobileNet architecture.

  Note that only TensorFlow is supported for now,
  therefore it only works with the data format
  `image_data_format='channels_last'` in your Keras config
  at `~/.keras/keras.json`.

  To load a MobileNet model via `load_model`, import the custom
  objects `relu6` and `DepthwiseConv2D` and pass them to the
  `custom_objects` parameter.
  E.g.
  model = load_model('mobilenet.h5', custom_objects={
                     'relu6': mobilenet.relu6,
                     'DepthwiseConv2D': mobilenet.DepthwiseConv2D})

  Arguments:
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or (3, 224, 224) (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 32.
          E.g. `(200, 200, 3)` would be one valid value.
      alpha: controls the width of the network.
          - If `alpha` < 1.0, proportionally decreases the number
              of filters in each layer.
          - If `alpha` > 1.0, proportionally increases the number
              of filters in each layer.
          - If `alpha` = 1, default number of filters from the paper
               are used at each layer.
      depth_multiplier: depth multiplier for depthwise convolution
          (also called the resolution multiplier)
      dropout: dropout rate
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of
          `layers.Input()`)
          to use as image input for the model.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model
              will be the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a
              2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
      RuntimeError: If attempting to run this model with a
          backend that does not support separable convolutions.
  """

  if K.backend() != 'tensorflow':
    raise RuntimeError('Only TensorFlow backend is currently supported, '
                       'as other backends do not support '
                       'depthwise convolution.')

  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as ImageNet with `include_top` '
                     'as true, `classes` should be 1000')

  # Determine proper input shape and default size.
  if input_shape is None:
    default_size = 224
  else:
    if K.image_data_format() == 'channels_first':
      rows = input_shape[1]
      cols = input_shape[2]
    else:
      rows = input_shape[0]
      cols = input_shape[1]

    if rows == cols and rows in [128, 160, 192, 224]:
      default_size = rows
    else:
      default_size = 224

  input_shape = _obtain_input_shape(
      input_shape,
      default_size=default_size,
      min_size=32,
      data_format=K.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if K.image_data_format() == 'channels_last':
    row_axis, col_axis = (0, 1)
  else:
    row_axis, col_axis = (1, 2)
  rows = input_shape[row_axis]
  cols = input_shape[col_axis]

  if weights == 'imagenet':
    if depth_multiplier != 1:
      raise ValueError('If imagenet weights are being loaded, '
                       'depth multiplier must be 1')

    if alpha not in [0.25, 0.50, 0.75, 1.0]:
      raise ValueError('If imagenet weights are being loaded, '
                       'alpha can be one of'
                       '`0.25`, `0.50`, `0.75` or `1.0` only.')

    if rows != cols or rows not in [128, 160, 192, 224]:
      raise ValueError('If imagenet weights are being loaded, '
                       'input must have a static square shape (one of '
                       '(128,128), (160,160), (192,192), or (224, 224)).'
                       ' Input shape provided = %s' % (input_shape,))

  if K.image_data_format() != 'channels_last':
    logging.warning('The MobileNet family of models is only available '
                    'for the input data format "channels_last" '
                    '(width, height, channels). '
                    'However your settings specify the default '
                    'data format "channels_first" (channels, width, height).'
                    ' You should set `image_data_format="channels_last"` '
                    'in your Keras config located at ~/.keras/keras.json. '
                    'The model being returned right now will expect inputs '
                    'to follow the "channels_last" data format.')
    K.set_image_data_format('channels_last')
    old_data_format = 'channels_first'
  else:
    old_data_format = None

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor

  x = _conv_block(img_input, 32, alpha, strides=(2, 2))
  x = _depthwise_conv_block(x, 64, alpha, depth_multiplier, block_id=1)

  x = _depthwise_conv_block(
      x, 128, alpha, depth_multiplier, strides=(2, 2), block_id=2)
  x = _depthwise_conv_block(x, 128, alpha, depth_multiplier, block_id=3)

  x = _depthwise_conv_block(
      x, 256, alpha, depth_multiplier, strides=(2, 2), block_id=4)
  x = _depthwise_conv_block(x, 256, alpha, depth_multiplier, block_id=5)

  x = _depthwise_conv_block(
      x, 512, alpha, depth_multiplier, strides=(2, 2), block_id=6)
  x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=7)
  x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=8)
  x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=9)
  x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=10)
  x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=11)

  x = _depthwise_conv_block(
      x, 1024, alpha, depth_multiplier, strides=(2, 2), block_id=12)
  x = _depthwise_conv_block(x, 1024, alpha, depth_multiplier, block_id=13)

  if include_top:
    if K.image_data_format() == 'channels_first':
      shape = (int(1024 * alpha), 1, 1)
    else:
      shape = (1, 1, int(1024 * alpha))

    x = GlobalAveragePooling2D()(x)
    x = Reshape(shape, name='reshape_1')(x)
    x = Dropout(dropout, name='dropout')(x)
    x = Conv2D(classes, (1, 1), padding='same', name='conv_preds')(x)
    x = Activation('softmax', name='act_softmax')(x)
    x = Reshape((classes,), name='reshape_2')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input

  # Create model.
  model = Model(inputs, x, name='mobilenet_%0.2f_%s' % (alpha, rows))

  # load weights
  if weights == 'imagenet':
    if K.image_data_format() == 'channels_first':
      raise ValueError('Weights for "channels_last" format '
                       'are not available.')
    if alpha == 1.0:
      alpha_text = '1_0'
    elif alpha == 0.75:
      alpha_text = '7_5'
    elif alpha == 0.50:
      alpha_text = '5_0'
    else:
      alpha_text = '2_5'

    if include_top:
      model_name = 'mobilenet_%s_%d_tf.h5' % (alpha_text, rows)
      weigh_path = BASE_WEIGHT_PATH + model_name
      weights_path = get_file(model_name, weigh_path, cache_subdir='models')
    else:
      model_name = 'mobilenet_%s_%d_tf_no_top.h5' % (alpha_text, rows)
      weigh_path = BASE_WEIGHT_PATH + model_name
      weights_path = get_file(model_name, weigh_path, cache_subdir='models')
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)

  if old_data_format:
    K.set_image_data_format(old_data_format)
  return model
Exemple #30
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def DenseNet(blocks,
             include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
  """Instantiates the DenseNet architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.

  The model and the weights are compatible with
  TensorFlow, Theano, and CNTK. The data format
  convention used by the model is the one
  specified in your Keras config file.

  Arguments:
      blocks: numbers of building blocks for the four dense layers.
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or `(3, 224, 224)` (with `channels_first` data format).
          It should have exactly 3 inputs channels.
      pooling: optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=224,
      min_size=221,
      data_format=K.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor

  bn_axis = 3 if K.image_data_format() == 'channels_last' else 1

  x = ZeroPadding2D(padding=((3, 3), (3, 3)))(img_input)
  x = Conv2D(64, 7, strides=2, use_bias=False, name='conv1/conv')(x)
  x = BatchNormalization(axis=bn_axis, epsilon=1.001e-5, name='conv1/bn')(x)
  x = Activation('relu', name='conv1/relu')(x)
  x = ZeroPadding2D(padding=((1, 1), (1, 1)))(x)
  x = MaxPooling2D(3, strides=2, name='pool1')(x)

  x = dense_block(x, blocks[0], name='conv2')
  x = transition_block(x, 0.5, name='pool2')
  x = dense_block(x, blocks[1], name='conv3')
  x = transition_block(x, 0.5, name='pool3')
  x = dense_block(x, blocks[2], name='conv4')
  x = transition_block(x, 0.5, name='pool4')
  x = dense_block(x, blocks[3], name='conv5')

  x = BatchNormalization(axis=bn_axis, epsilon=1.001e-5, name='bn')(x)

  if include_top:
    x = GlobalAveragePooling2D(name='avg_pool')(x)
    x = Dense(classes, activation='softmax', name='fc1000')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D(name='avg_pool')(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D(name='max_pool')(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input

  # Create model.
  if blocks == [6, 12, 24, 16]:
    model = Model(inputs, x, name='densenet121')
  elif blocks == [6, 12, 32, 32]:
    model = Model(inputs, x, name='densenet169')
  elif blocks == [6, 12, 48, 32]:
    model = Model(inputs, x, name='densenet201')
  else:
    model = Model(inputs, x, name='densenet')

  # Load weights.
  if weights == 'imagenet':
    if include_top:
      if blocks == [6, 12, 24, 16]:
        weights_path = get_file(
            'densenet121_weights_tf_dim_ordering_tf_kernels.h5',
            DENSENET121_WEIGHT_PATH,
            cache_subdir='models',
            file_hash='0962ca643bae20f9b6771cb844dca3b0')
      elif blocks == [6, 12, 32, 32]:
        weights_path = get_file(
            'densenet169_weights_tf_dim_ordering_tf_kernels.h5',
            DENSENET169_WEIGHT_PATH,
            cache_subdir='models',
            file_hash='bcf9965cf5064a5f9eb6d7dc69386f43')
      elif blocks == [6, 12, 48, 32]:
        weights_path = get_file(
            'densenet201_weights_tf_dim_ordering_tf_kernels.h5',
            DENSENET201_WEIGHT_PATH,
            cache_subdir='models',
            file_hash='7bb75edd58cb43163be7e0005fbe95ef')
    else:
      if blocks == [6, 12, 24, 16]:
        weights_path = get_file(
            'densenet121_weights_tf_dim_ordering_tf_kernels_notop.h5',
            DENSENET121_WEIGHT_PATH_NO_TOP,
            cache_subdir='models',
            file_hash='4912a53fbd2a69346e7f2c0b5ec8c6d3')
      elif blocks == [6, 12, 32, 32]:
        weights_path = get_file(
            'densenet169_weights_tf_dim_ordering_tf_kernels_notop.h5',
            DENSENET169_WEIGHT_PATH_NO_TOP,
            cache_subdir='models',
            file_hash='50662582284e4cf834ce40ab4dfa58c6')
      elif blocks == [6, 12, 48, 32]:
        weights_path = get_file(
            'densenet201_weights_tf_dim_ordering_tf_kernels_notop.h5',
            DENSENET201_WEIGHT_PATH_NO_TOP,
            cache_subdir='models',
            file_hash='1c2de60ee40562448dbac34a0737e798')
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)

  return model
Exemple #31
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def load_data(path='imdb.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3):
    """Loads the IMDB dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: truncate sequences after this length.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case `maxlen` is so low
          that no input sequence could be kept.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
    path = get_file(path,
                    origin='https://s3.amazonaws.com/text-datasets/imdb.npz')
    f = np.load(path, allow_pickle=True)
    x_train = f['x_train']
    labels_train = f['y_train']
    x_test = f['x_test']
    labels_test = f['y_test']
    f.close()

    np.random.seed(seed)
    np.random.shuffle(x_train)
    np.random.seed(seed)
    np.random.shuffle(labels_train)

    np.random.seed(seed * 2)
    np.random.shuffle(x_test)
    np.random.seed(seed * 2)
    np.random.shuffle(labels_test)

    xs = np.concatenate([x_train, x_test])
    labels = np.concatenate([labels_train, labels_test])

    if start_char is not None:
        xs = [[start_char] + [w + index_from for w in x] for x in xs]
    elif index_from:
        xs = [[w + index_from for w in x] for x in xs]

    if maxlen:
        new_xs = []
        new_labels = []
        for x, y in zip(xs, labels):
            if len(x) < maxlen:
                new_xs.append(x)
                new_labels.append(y)
        xs = new_xs
        labels = new_labels
        if not xs:
            raise ValueError(
                'After filtering for sequences shorter than maxlen=' +
                str(maxlen) + ', no sequence was kept. '
                'Increase maxlen.')
    if not num_words:
        num_words = max([max(x) for x in xs])

    # by convention, use 2 as OOV word
    # reserve 'index_from' (=3 by default) characters:
    # 0 (padding), 1 (start), 2 (OOV)
    if oov_char is not None:
        xs = [[oov_char if (w >= num_words or w < skip_top) else w for w in x]
              for x in xs]
    else:
        new_xs = []
        for x in xs:
            nx = []
            for w in x:
                if skip_top <= w < num_words:
                    nx.append(w)
            new_xs.append(nx)
        xs = new_xs

    x_train = np.array(xs[:len(x_train)])
    y_train = np.array(labels[:len(x_train)])

    x_test = np.array(xs[len(x_train):])
    y_test = np.array(labels[len(x_train):])

    return (x_train, y_train), (x_test, y_test)
Exemple #32
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def DenseNet(blocks,
             include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
    """Instantiates the DenseNet architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.

  The model and the weights are compatible with
  TensorFlow, Theano, and CNTK. The data format
  convention used by the model is the one
  specified in your Keras config file.

  Arguments:
      blocks: numbers of building blocks for the four dense layers.
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or `(3, 224, 224)` (with `channels_first` data format).
          It should have exactly 3 inputs channels.
      pooling: optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
    if not (weights in {'imagenet', None} or os.path.exists(weights)):
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization), `imagenet` '
                         '(pre-training on ImageNet), '
                         'or the path to the weights file to be loaded.')

    if weights == 'imagenet' and include_top and classes != 1000:
        raise ValueError('If using `weights` as imagenet with `include_top`'
                         ' as true, `classes` should be 1000')

    # Determine proper input shape
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=221,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

    bn_axis = 3 if K.image_data_format() == 'channels_last' else 1

    x = ZeroPadding2D(padding=((3, 3), (3, 3)))(img_input)
    x = Conv2D(64, 7, strides=2, use_bias=False, name='conv1/conv')(x)
    x = BatchNormalization(axis=bn_axis, epsilon=1.001e-5, name='conv1/bn')(x)
    x = Activation('relu', name='conv1/relu')(x)
    x = ZeroPadding2D(padding=((1, 1), (1, 1)))(x)
    x = MaxPooling2D(3, strides=2, name='pool1')(x)

    x = dense_block(x, blocks[0], name='conv2')
    x = transition_block(x, 0.5, name='pool2')
    x = dense_block(x, blocks[1], name='conv3')
    x = transition_block(x, 0.5, name='pool3')
    x = dense_block(x, blocks[2], name='conv4')
    x = transition_block(x, 0.5, name='pool4')
    x = dense_block(x, blocks[3], name='conv5')

    x = BatchNormalization(axis=bn_axis, epsilon=1.001e-5, name='bn')(x)

    if include_top:
        x = GlobalAveragePooling2D(name='avg_pool')(x)
        x = Dense(classes, activation='softmax', name='fc1000')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D(name='max_pool')(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    if blocks == [6, 12, 24, 16]:
        model = Model(inputs, x, name='densenet121')
    elif blocks == [6, 12, 32, 32]:
        model = Model(inputs, x, name='densenet169')
    elif blocks == [6, 12, 48, 32]:
        model = Model(inputs, x, name='densenet201')
    else:
        model = Model(inputs, x, name='densenet')

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            if blocks == [6, 12, 24, 16]:
                weights_path = get_file(
                    'densenet121_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET121_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='0962ca643bae20f9b6771cb844dca3b0')
            elif blocks == [6, 12, 32, 32]:
                weights_path = get_file(
                    'densenet169_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET169_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='bcf9965cf5064a5f9eb6d7dc69386f43')
            elif blocks == [6, 12, 48, 32]:
                weights_path = get_file(
                    'densenet201_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET201_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='7bb75edd58cb43163be7e0005fbe95ef')
        else:
            if blocks == [6, 12, 24, 16]:
                weights_path = get_file(
                    'densenet121_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET121_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='4912a53fbd2a69346e7f2c0b5ec8c6d3')
            elif blocks == [6, 12, 32, 32]:
                weights_path = get_file(
                    'densenet169_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET169_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='50662582284e4cf834ce40ab4dfa58c6')
            elif blocks == [6, 12, 48, 32]:
                weights_path = get_file(
                    'densenet201_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET201_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='1c2de60ee40562448dbac34a0737e798')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
def InceptionResNetV2(include_top=True,
                      weights='imagenet',
                      input_tensor=None,
                      input_shape=None,
                      pooling=None,
                      classes=1000):
  """Instantiates the Inception-ResNet v2 architecture.

  Optionally loads weights pre-trained on ImageNet.
  Note that when using TensorFlow, for best performance you should
  set `"image_data_format": "channels_last"` in your Keras config
  at `~/.keras/keras.json`.

  The model and the weights are compatible with TensorFlow, Theano and
  CNTK backends. The data format convention used by the model is
  the one specified in your Keras config file.

  Note that the default input image size for this model is 299x299, instead
  of 224x224 as in the VGG16 and ResNet models. Also, the input preprocessing
  function is different (i.e., do not use `imagenet_utils.preprocess_input()`
  with this model. Use `preprocess_input()` defined in this module instead).

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is `False` (otherwise the input shape
          has to be `(299, 299, 3)` (with `'channels_last'` data format)
          or `(3, 299, 299)` (with `'channels_first'` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 139.
          E.g. `(150, 150, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the last convolutional layer.
          - `'avg'` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `'max'` means that global max pooling will be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is `True`, and
          if no `weights` argument is specified.

  Returns:
      A Keras `Model` instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=299,
      min_size=139,
      data_format=K.image_data_format(),
      require_flatten=False,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor

  # Stem block: 35 x 35 x 192
  x = conv2d_bn(img_input, 32, 3, strides=2, padding='valid')
  x = conv2d_bn(x, 32, 3, padding='valid')
  x = conv2d_bn(x, 64, 3)
  x = MaxPooling2D(3, strides=2)(x)
  x = conv2d_bn(x, 80, 1, padding='valid')
  x = conv2d_bn(x, 192, 3, padding='valid')
  x = MaxPooling2D(3, strides=2)(x)

  # Mixed 5b (Inception-A block): 35 x 35 x 320
  branch_0 = conv2d_bn(x, 96, 1)
  branch_1 = conv2d_bn(x, 48, 1)
  branch_1 = conv2d_bn(branch_1, 64, 5)
  branch_2 = conv2d_bn(x, 64, 1)
  branch_2 = conv2d_bn(branch_2, 96, 3)
  branch_2 = conv2d_bn(branch_2, 96, 3)
  branch_pool = AveragePooling2D(3, strides=1, padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 64, 1)
  branches = [branch_0, branch_1, branch_2, branch_pool]
  channel_axis = 1 if K.image_data_format() == 'channels_first' else 3
  x = Concatenate(axis=channel_axis, name='mixed_5b')(branches)

  # 10x block35 (Inception-ResNet-A block): 35 x 35 x 320
  for block_idx in range(1, 11):
    x = inception_resnet_block(
        x, scale=0.17, block_type='block35', block_idx=block_idx)

  # Mixed 6a (Reduction-A block): 17 x 17 x 1088
  branch_0 = conv2d_bn(x, 384, 3, strides=2, padding='valid')
  branch_1 = conv2d_bn(x, 256, 1)
  branch_1 = conv2d_bn(branch_1, 256, 3)
  branch_1 = conv2d_bn(branch_1, 384, 3, strides=2, padding='valid')
  branch_pool = MaxPooling2D(3, strides=2, padding='valid')(x)
  branches = [branch_0, branch_1, branch_pool]
  x = Concatenate(axis=channel_axis, name='mixed_6a')(branches)

  # 20x block17 (Inception-ResNet-B block): 17 x 17 x 1088
  for block_idx in range(1, 21):
    x = inception_resnet_block(
        x, scale=0.1, block_type='block17', block_idx=block_idx)

  # Mixed 7a (Reduction-B block): 8 x 8 x 2080
  branch_0 = conv2d_bn(x, 256, 1)
  branch_0 = conv2d_bn(branch_0, 384, 3, strides=2, padding='valid')
  branch_1 = conv2d_bn(x, 256, 1)
  branch_1 = conv2d_bn(branch_1, 288, 3, strides=2, padding='valid')
  branch_2 = conv2d_bn(x, 256, 1)
  branch_2 = conv2d_bn(branch_2, 288, 3)
  branch_2 = conv2d_bn(branch_2, 320, 3, strides=2, padding='valid')
  branch_pool = MaxPooling2D(3, strides=2, padding='valid')(x)
  branches = [branch_0, branch_1, branch_2, branch_pool]
  x = Concatenate(axis=channel_axis, name='mixed_7a')(branches)

  # 10x block8 (Inception-ResNet-C block): 8 x 8 x 2080
  for block_idx in range(1, 10):
    x = inception_resnet_block(
        x, scale=0.2, block_type='block8', block_idx=block_idx)
  x = inception_resnet_block(
      x, scale=1., activation=None, block_type='block8', block_idx=10)

  # Final convolution block: 8 x 8 x 1536
  x = conv2d_bn(x, 1536, 1, name='conv_7b')

  if include_top:
    # Classification block
    x = GlobalAveragePooling2D(name='avg_pool')(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input

  # Create model
  model = Model(inputs, x, name='inception_resnet_v2')

  # Load weights
  if weights == 'imagenet':
    if include_top:
      fname = 'inception_resnet_v2_weights_tf_dim_ordering_tf_kernels.h5'
      weights_path = get_file(
          fname,
          BASE_WEIGHT_URL + fname,
          cache_subdir='models',
          file_hash='e693bd0210a403b3192acc6073ad2e96')
    else:
      fname = 'inception_resnet_v2_weights_tf_dim_ordering_tf_kernels_notop.h5'
      weights_path = get_file(
          fname,
          BASE_WEIGHT_URL + fname,
          cache_subdir='models',
          file_hash='d19885ff4a710c122648d3b5c3b684e4')
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)

  return model
Exemple #34
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def MobileNet(input_shape=None,
              alpha=1.0,
              depth_multiplier=1,
              dropout=1e-3,
              include_top=True,
              weights='imagenet',
              input_tensor=None,
              pooling=None,
              classes=1000):
    """Instantiates the MobileNet architecture.

  Note that only TensorFlow is supported for now,
  therefore it only works with the data format
  `image_data_format='channels_last'` in your Keras config
  at `~/.keras/keras.json`.

  To load a MobileNet model via `load_model`, import the custom
  objects `relu6` and `DepthwiseConv2D` and pass them to the
  `custom_objects` parameter.
  E.g.
  model = load_model('mobilenet.h5', custom_objects={
                     'relu6': mobilenet.relu6,
                     'DepthwiseConv2D': mobilenet.DepthwiseConv2D})

  Arguments:
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or (3, 224, 224) (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 32.
          E.g. `(200, 200, 3)` would be one valid value.
      alpha: controls the width of the network.
          - If `alpha` < 1.0, proportionally decreases the number
              of filters in each layer.
          - If `alpha` > 1.0, proportionally increases the number
              of filters in each layer.
          - If `alpha` = 1, default number of filters from the paper
               are used at each layer.
      depth_multiplier: depth multiplier for depthwise convolution
          (also called the resolution multiplier)
      dropout: dropout rate
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of
          `layers.Input()`)
          to use as image input for the model.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model
              will be the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a
              2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
      RuntimeError: If attempting to run this model with a
          backend that does not support separable convolutions.
  """

    if K.backend() != 'tensorflow':
        raise RuntimeError('Only TensorFlow backend is currently supported, '
                           'as other backends do not support '
                           'depthwise convolution.')

    if not (weights in {'imagenet', None} or os.path.exists(weights)):
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization), `imagenet` '
                         '(pre-training on ImageNet), '
                         'or the path to the weights file to be loaded.')

    if weights == 'imagenet' and include_top and classes != 1000:
        raise ValueError('If using `weights` as ImageNet with `include_top` '
                         'as true, `classes` should be 1000')

    # Determine proper input shape and default size.
    if input_shape is None:
        default_size = 224
    else:
        if K.image_data_format() == 'channels_first':
            rows = input_shape[1]
            cols = input_shape[2]
        else:
            rows = input_shape[0]
            cols = input_shape[1]

        if rows == cols and rows in [128, 160, 192, 224]:
            default_size = rows
        else:
            default_size = 224

    input_shape = _obtain_input_shape(input_shape,
                                      default_size=default_size,
                                      min_size=32,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if K.image_data_format() == 'channels_last':
        row_axis, col_axis = (0, 1)
    else:
        row_axis, col_axis = (1, 2)
    rows = input_shape[row_axis]
    cols = input_shape[col_axis]

    if weights == 'imagenet':
        if depth_multiplier != 1:
            raise ValueError('If imagenet weights are being loaded, '
                             'depth multiplier must be 1')

        if alpha not in [0.25, 0.50, 0.75, 1.0]:
            raise ValueError('If imagenet weights are being loaded, '
                             'alpha can be one of'
                             '`0.25`, `0.50`, `0.75` or `1.0` only.')

        if rows != cols or rows not in [128, 160, 192, 224]:
            raise ValueError('If imagenet weights are being loaded, '
                             'input must have a static square shape (one of '
                             '(128,128), (160,160), (192,192), or (224, 224)).'
                             ' Input shape provided = %s' % (input_shape, ))

    if K.image_data_format() != 'channels_last':
        logging.warning(
            'The MobileNet family of models is only available '
            'for the input data format "channels_last" '
            '(width, height, channels). '
            'However your settings specify the default '
            'data format "channels_first" (channels, width, height).'
            ' You should set `image_data_format="channels_last"` '
            'in your Keras config located at ~/.keras/keras.json. '
            'The model being returned right now will expect inputs '
            'to follow the "channels_last" data format.')
        K.set_image_data_format('channels_last')
        old_data_format = 'channels_first'
    else:
        old_data_format = None

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

    x = _conv_block(img_input, 32, alpha, strides=(2, 2))
    x = _depthwise_conv_block(x, 64, alpha, depth_multiplier, block_id=1)

    x = _depthwise_conv_block(x,
                              128,
                              alpha,
                              depth_multiplier,
                              strides=(2, 2),
                              block_id=2)
    x = _depthwise_conv_block(x, 128, alpha, depth_multiplier, block_id=3)

    x = _depthwise_conv_block(x,
                              256,
                              alpha,
                              depth_multiplier,
                              strides=(2, 2),
                              block_id=4)
    x = _depthwise_conv_block(x, 256, alpha, depth_multiplier, block_id=5)

    x = _depthwise_conv_block(x,
                              512,
                              alpha,
                              depth_multiplier,
                              strides=(2, 2),
                              block_id=6)
    x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=7)
    x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=8)
    x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=9)
    x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=10)
    x = _depthwise_conv_block(x, 512, alpha, depth_multiplier, block_id=11)

    x = _depthwise_conv_block(x,
                              1024,
                              alpha,
                              depth_multiplier,
                              strides=(2, 2),
                              block_id=12)
    x = _depthwise_conv_block(x, 1024, alpha, depth_multiplier, block_id=13)

    if include_top:
        if K.image_data_format() == 'channels_first':
            shape = (int(1024 * alpha), 1, 1)
        else:
            shape = (1, 1, int(1024 * alpha))

        x = GlobalAveragePooling2D()(x)
        x = Reshape(shape, name='reshape_1')(x)
        x = Dropout(dropout, name='dropout')(x)
        x = Conv2D(classes, (1, 1), padding='same', name='conv_preds')(x)
        x = Activation('softmax', name='act_softmax')(x)
        x = Reshape((classes, ), name='reshape_2')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    model = Model(inputs, x, name='mobilenet_%0.2f_%s' % (alpha, rows))

    # load weights
    if weights == 'imagenet':
        if K.image_data_format() == 'channels_first':
            raise ValueError('Weights for "channels_last" format '
                             'are not available.')
        if alpha == 1.0:
            alpha_text = '1_0'
        elif alpha == 0.75:
            alpha_text = '7_5'
        elif alpha == 0.50:
            alpha_text = '5_0'
        else:
            alpha_text = '2_5'

        if include_top:
            model_name = 'mobilenet_%s_%d_tf.h5' % (alpha_text, rows)
            weigh_path = BASE_WEIGHT_PATH + model_name
            weights_path = get_file(model_name,
                                    weigh_path,
                                    cache_subdir='models')
        else:
            model_name = 'mobilenet_%s_%d_tf_no_top.h5' % (alpha_text, rows)
            weigh_path = BASE_WEIGHT_PATH + model_name
            weights_path = get_file(model_name,
                                    weigh_path,
                                    cache_subdir='models')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    if old_data_format:
        K.set_image_data_format(old_data_format)
    return model
Exemple #35
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def InceptionV3(include_top=True,
                weights='imagenet',
                input_tensor=None,
                input_shape=None,
                pooling=None,
                classes=1000):
  """Instantiates the Inception v3 architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format="channels_last"` in your Keras config
  at ~/.keras/keras.json.
  The model and the weights are compatible with both
  TensorFlow and Theano. The data format
  convention used by the model is the one
  specified in your Keras config file.
  Note that the default input image size for this model is 299x299.

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization)
          or "imagenet" (pre-training on ImageNet).
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(299, 299, 3)` (with `channels_last` data format)
          or `(3, 299, 299)` (with `channels_first` data format).
          It should have exactly 3 input channels,
          and width and height should be no smaller than 139.
          E.g. `(150, 150, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if weights not in {'imagenet', None}:
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization) or `imagenet` '
                     '(pre-training on ImageNet).')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=299,
      min_size=139,
      data_format=K.image_data_format(),
      require_flatten=False,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    img_input = Input(tensor=input_tensor, shape=input_shape)

  if K.image_data_format() == 'channels_first':
    channel_axis = 1
  else:
    channel_axis = 3

  x = conv2d_bn(img_input, 32, 3, 3, strides=(2, 2), padding='valid')
  x = conv2d_bn(x, 32, 3, 3, padding='valid')
  x = conv2d_bn(x, 64, 3, 3)
  x = MaxPooling2D((3, 3), strides=(2, 2))(x)

  x = conv2d_bn(x, 80, 1, 1, padding='valid')
  x = conv2d_bn(x, 192, 3, 3, padding='valid')
  x = MaxPooling2D((3, 3), strides=(2, 2))(x)

  # mixed 0, 1, 2: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 32, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed0')

  # mixed 1: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 64, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed1')

  # mixed 2: 35 x 35 x 256
  branch1x1 = conv2d_bn(x, 64, 1, 1)

  branch5x5 = conv2d_bn(x, 48, 1, 1)
  branch5x5 = conv2d_bn(branch5x5, 64, 5, 5)

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 64, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch5x5, branch3x3dbl, branch_pool],
      axis=channel_axis,
      name='mixed2')

  # mixed 3: 17 x 17 x 768
  branch3x3 = conv2d_bn(x, 384, 3, 3, strides=(2, 2), padding='valid')

  branch3x3dbl = conv2d_bn(x, 64, 1, 1)
  branch3x3dbl = conv2d_bn(branch3x3dbl, 96, 3, 3)
  branch3x3dbl = conv2d_bn(
      branch3x3dbl, 96, 3, 3, strides=(2, 2), padding='valid')

  branch_pool = MaxPooling2D((3, 3), strides=(2, 2))(x)
  x = layers.concatenate(
      [branch3x3, branch3x3dbl, branch_pool], axis=channel_axis, name='mixed3')

  # mixed 4: 17 x 17 x 768
  branch1x1 = conv2d_bn(x, 192, 1, 1)

  branch7x7 = conv2d_bn(x, 128, 1, 1)
  branch7x7 = conv2d_bn(branch7x7, 128, 1, 7)
  branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

  branch7x7dbl = conv2d_bn(x, 128, 1, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 1, 7)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 128, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch7x7, branch7x7dbl, branch_pool],
      axis=channel_axis,
      name='mixed4')

  # mixed 5, 6: 17 x 17 x 768
  for i in range(2):
    branch1x1 = conv2d_bn(x, 192, 1, 1)

    branch7x7 = conv2d_bn(x, 160, 1, 1)
    branch7x7 = conv2d_bn(branch7x7, 160, 1, 7)
    branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

    branch7x7dbl = conv2d_bn(x, 160, 1, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 7, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 1, 7)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 160, 7, 1)
    branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

    branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
    branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
    x = layers.concatenate(
        [branch1x1, branch7x7, branch7x7dbl, branch_pool],
        axis=channel_axis,
        name='mixed' + str(5 + i))

  # mixed 7: 17 x 17 x 768
  branch1x1 = conv2d_bn(x, 192, 1, 1)

  branch7x7 = conv2d_bn(x, 192, 1, 1)
  branch7x7 = conv2d_bn(branch7x7, 192, 1, 7)
  branch7x7 = conv2d_bn(branch7x7, 192, 7, 1)

  branch7x7dbl = conv2d_bn(x, 192, 1, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 7, 1)
  branch7x7dbl = conv2d_bn(branch7x7dbl, 192, 1, 7)

  branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
  branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
  x = layers.concatenate(
      [branch1x1, branch7x7, branch7x7dbl, branch_pool],
      axis=channel_axis,
      name='mixed7')

  # mixed 8: 8 x 8 x 1280
  branch3x3 = conv2d_bn(x, 192, 1, 1)
  branch3x3 = conv2d_bn(branch3x3, 320, 3, 3, strides=(2, 2), padding='valid')

  branch7x7x3 = conv2d_bn(x, 192, 1, 1)
  branch7x7x3 = conv2d_bn(branch7x7x3, 192, 1, 7)
  branch7x7x3 = conv2d_bn(branch7x7x3, 192, 7, 1)
  branch7x7x3 = conv2d_bn(
      branch7x7x3, 192, 3, 3, strides=(2, 2), padding='valid')

  branch_pool = MaxPooling2D((3, 3), strides=(2, 2))(x)
  x = layers.concatenate(
      [branch3x3, branch7x7x3, branch_pool], axis=channel_axis, name='mixed8')

  # mixed 9: 8 x 8 x 2048
  for i in range(2):
    branch1x1 = conv2d_bn(x, 320, 1, 1)

    branch3x3 = conv2d_bn(x, 384, 1, 1)
    branch3x3_1 = conv2d_bn(branch3x3, 384, 1, 3)
    branch3x3_2 = conv2d_bn(branch3x3, 384, 3, 1)
    branch3x3 = layers.concatenate(
        [branch3x3_1, branch3x3_2], axis=channel_axis, name='mixed9_' + str(i))

    branch3x3dbl = conv2d_bn(x, 448, 1, 1)
    branch3x3dbl = conv2d_bn(branch3x3dbl, 384, 3, 3)
    branch3x3dbl_1 = conv2d_bn(branch3x3dbl, 384, 1, 3)
    branch3x3dbl_2 = conv2d_bn(branch3x3dbl, 384, 3, 1)
    branch3x3dbl = layers.concatenate(
        [branch3x3dbl_1, branch3x3dbl_2], axis=channel_axis)

    branch_pool = AveragePooling2D((3, 3), strides=(1, 1), padding='same')(x)
    branch_pool = conv2d_bn(branch_pool, 192, 1, 1)
    x = layers.concatenate(
        [branch1x1, branch3x3, branch3x3dbl, branch_pool],
        axis=channel_axis,
        name='mixed' + str(9 + i))
  if include_top:
    # Classification block
    x = GlobalAveragePooling2D(name='avg_pool')(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input
  # Create model.
  model = Model(inputs, x, name='inception_v3')

  # load weights
  if weights == 'imagenet':
    if include_top:
      weights_path = get_file(
          'inception_v3_weights_tf_dim_ordering_tf_kernels.h5',
          WEIGHTS_PATH,
          cache_subdir='models',
          file_hash='9a0d58056eeedaa3f26cb7ebd46da564')
    else:
      weights_path = get_file(
          'inception_v3_weights_tf_dim_ordering_tf_kernels_notop.h5',
          WEIGHTS_PATH_NO_TOP,
          cache_subdir='models',
          file_hash='bcbd6486424b2319ff4ef7d526e38f63')
    model.load_weights(weights_path)
  return model
def load_data(path='reuters.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              test_split=0.2,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3,
              **kwargs):
  """Loads the Reuters newswire classification dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: truncate sequences after this length.
      test_split: Fraction of the dataset to be used as test data.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.
      **kwargs: Used for backwards compatibility.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
  # Legacy support
  if 'nb_words' in kwargs:
    logging.warning('The `nb_words` argument in `load_data` '
                    'has been renamed `num_words`.')
    num_words = kwargs.pop('nb_words')
  if kwargs:
    raise TypeError('Unrecognized keyword arguments: ' + str(kwargs))

  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/reuters.npz',
      file_hash='87aedbeb0cb229e378797a632c1997b6')
  with np.load(path) as f:
    xs, labels = f['x'], f['y']

  np.random.seed(seed)
  indices = np.arange(len(xs))
  np.random.shuffle(indices)
  xs = xs[indices]
  labels = labels[indices]

  if start_char is not None:
    xs = [[start_char] + [w + index_from for w in x] for x in xs]
  elif index_from:
    xs = [[w + index_from for w in x] for x in xs]

  if maxlen:
    xs, labels = _remove_long_seq(maxlen, xs, labels)

  if not num_words:
    num_words = max([max(x) for x in xs])

  # by convention, use 2 as OOV word
  # reserve 'index_from' (=3 by default) characters:
  # 0 (padding), 1 (start), 2 (OOV)
  if oov_char is not None:
    xs = [[w if skip_top <= w < num_words else oov_char for w in x] for x in xs]
  else:
    xs = [[w for w in x if skip_top <= w < num_words] for x in xs]

  idx = int(len(xs) * (1 - test_split))
  x_train, y_train = np.array(xs[:idx]), np.array(labels[:idx])
  x_test, y_test = np.array(xs[idx:]), np.array(labels[idx:])

  return (x_train, y_train), (x_test, y_test)
Exemple #37
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def load_data(path='imdb.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3,
              **kwargs):
  """Loads the IMDB dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: sequences longer than this will be filtered out.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.
      **kwargs: Used for backwards compatibility.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case `maxlen` is so low
          that no input sequence could be kept.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
  # Legacy support
  if 'nb_words' in kwargs:
    logging.warning('The `nb_words` argument in `load_data` '
                    'has been renamed `num_words`.')
    num_words = kwargs.pop('nb_words')
  if kwargs:
    raise TypeError('Unrecognized keyword arguments: ' + str(kwargs))

  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/imdb.npz',
      file_hash='599dadb1135973df5b59232a0e9a887c')
  with np.load(path) as f:
    x_train, labels_train = f['x_train'], f['y_train']
    x_test, labels_test = f['x_test'], f['y_test']

  np.random.seed(seed)
  indices = np.arange(len(x_train))
  np.random.shuffle(indices)
  x_train = x_train[indices]
  labels_train = labels_train[indices]

  indices = np.arange(len(x_test))
  np.random.shuffle(indices)
  x_test = x_test[indices]
  labels_test = labels_test[indices]

  xs = np.concatenate([x_train, x_test])
  labels = np.concatenate([labels_train, labels_test])

  if start_char is not None:
    xs = [[start_char] + [w + index_from for w in x] for x in xs]
  elif index_from:
    xs = [[w + index_from for w in x] for x in xs]

  if maxlen:
    xs, labels = _remove_long_seq(maxlen, xs, labels)
    if not xs:
      raise ValueError('After filtering for sequences shorter than maxlen=' +
                       str(maxlen) + ', no sequence was kept. '
                       'Increase maxlen.')
  if not num_words:
    num_words = max([max(x) for x in xs])

  # by convention, use 2 as OOV word
  # reserve 'index_from' (=3 by default) characters:
  # 0 (padding), 1 (start), 2 (OOV)
  if oov_char is not None:
    xs = [
        [w if (skip_top <= w < num_words) else oov_char for w in x] for x in xs
    ]
  else:
    xs = [[w for w in x if skip_top <= w < num_words] for x in xs]

  idx = len(x_train)
  x_train, y_train = np.array(xs[:idx]), np.array(labels[:idx])
  x_test, y_test = np.array(xs[idx:]), np.array(labels[idx:])

  return (x_train, y_train), (x_test, y_test)
Exemple #38
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def Xception(include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
  """Instantiates the Xception architecture.

  Optionally loads weights pre-trained
  on ImageNet. This model is available for TensorFlow only,
  and can only be used with inputs following the TensorFlow
  data format `(width, height, channels)`.
  You should set `image_data_format="channels_last"` in your Keras config
  located at ~/.keras/keras.json.

  Note that the default input image size for this model is 299x299.

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
          'imagenet' (pre-training on ImageNet),
          or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(299, 299, 3)`.
          It should have exactly 3 input channels,
          and width and height should be no smaller than 71.
          E.g. `(150, 150, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
      RuntimeError: If attempting to run this model with a
          backend that does not support separable convolutions.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  if K.backend() != 'tensorflow':
    raise RuntimeError('The Xception model is only available with '
                       'the TensorFlow backend.')
  if K.image_data_format() != 'channels_last':
    logging.warning(
        'The Xception model is only available for the '
        'input data format "channels_last" '
        '(width, height, channels). '
        'However your settings specify the default '
        'data format "channels_first" (channels, width, height). '
        'You should set `image_data_format="channels_last"` in your Keras '
        'config located at ~/.keras/keras.json. '
        'The model being returned right now will expect inputs '
        'to follow the "channels_last" data format.')
    K.set_image_data_format('channels_last')
    old_data_format = 'channels_first'
  else:
    old_data_format = None

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=299,
      min_size=71,
      data_format=K.image_data_format(),
      require_flatten=False,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    img_input = Input(tensor=input_tensor, shape=input_shape)

  x = Conv2D(
      32, (3, 3), strides=(2, 2), use_bias=False,
      name='block1_conv1')(img_input)
  x = BatchNormalization(name='block1_conv1_bn')(x)
  x = Activation('relu', name='block1_conv1_act')(x)
  x = Conv2D(64, (3, 3), use_bias=False, name='block1_conv2')(x)
  x = BatchNormalization(name='block1_conv2_bn')(x)
  x = Activation('relu', name='block1_conv2_act')(x)

  residual = Conv2D(
      128, (1, 1), strides=(2, 2), padding='same', use_bias=False)(x)
  residual = BatchNormalization()(residual)

  x = SeparableConv2D(
      128, (3, 3), padding='same', use_bias=False, name='block2_sepconv1')(x)
  x = BatchNormalization(name='block2_sepconv1_bn')(x)
  x = Activation('relu', name='block2_sepconv2_act')(x)
  x = SeparableConv2D(
      128, (3, 3), padding='same', use_bias=False, name='block2_sepconv2')(x)
  x = BatchNormalization(name='block2_sepconv2_bn')(x)

  x = MaxPooling2D(
      (3, 3), strides=(2, 2), padding='same', name='block2_pool')(x)
  x = layers.add([x, residual])

  residual = Conv2D(
      256, (1, 1), strides=(2, 2), padding='same', use_bias=False)(x)
  residual = BatchNormalization()(residual)

  x = Activation('relu', name='block3_sepconv1_act')(x)
  x = SeparableConv2D(
      256, (3, 3), padding='same', use_bias=False, name='block3_sepconv1')(x)
  x = BatchNormalization(name='block3_sepconv1_bn')(x)
  x = Activation('relu', name='block3_sepconv2_act')(x)
  x = SeparableConv2D(
      256, (3, 3), padding='same', use_bias=False, name='block3_sepconv2')(x)
  x = BatchNormalization(name='block3_sepconv2_bn')(x)

  x = MaxPooling2D(
      (3, 3), strides=(2, 2), padding='same', name='block3_pool')(x)
  x = layers.add([x, residual])

  residual = Conv2D(
      728, (1, 1), strides=(2, 2), padding='same', use_bias=False)(x)
  residual = BatchNormalization()(residual)

  x = Activation('relu', name='block4_sepconv1_act')(x)
  x = SeparableConv2D(
      728, (3, 3), padding='same', use_bias=False, name='block4_sepconv1')(x)
  x = BatchNormalization(name='block4_sepconv1_bn')(x)
  x = Activation('relu', name='block4_sepconv2_act')(x)
  x = SeparableConv2D(
      728, (3, 3), padding='same', use_bias=False, name='block4_sepconv2')(x)
  x = BatchNormalization(name='block4_sepconv2_bn')(x)

  x = MaxPooling2D(
      (3, 3), strides=(2, 2), padding='same', name='block4_pool')(x)
  x = layers.add([x, residual])

  for i in range(8):
    residual = x
    prefix = 'block' + str(i + 5)

    x = Activation('relu', name=prefix + '_sepconv1_act')(x)
    x = SeparableConv2D(
        728, (3, 3), padding='same', use_bias=False,
        name=prefix + '_sepconv1')(x)
    x = BatchNormalization(name=prefix + '_sepconv1_bn')(x)
    x = Activation('relu', name=prefix + '_sepconv2_act')(x)
    x = SeparableConv2D(
        728, (3, 3), padding='same', use_bias=False,
        name=prefix + '_sepconv2')(x)
    x = BatchNormalization(name=prefix + '_sepconv2_bn')(x)
    x = Activation('relu', name=prefix + '_sepconv3_act')(x)
    x = SeparableConv2D(
        728, (3, 3), padding='same', use_bias=False,
        name=prefix + '_sepconv3')(x)
    x = BatchNormalization(name=prefix + '_sepconv3_bn')(x)

    x = layers.add([x, residual])

  residual = Conv2D(
      1024, (1, 1), strides=(2, 2), padding='same', use_bias=False)(x)
  residual = BatchNormalization()(residual)

  x = Activation('relu', name='block13_sepconv1_act')(x)
  x = SeparableConv2D(
      728, (3, 3), padding='same', use_bias=False, name='block13_sepconv1')(x)
  x = BatchNormalization(name='block13_sepconv1_bn')(x)
  x = Activation('relu', name='block13_sepconv2_act')(x)
  x = SeparableConv2D(
      1024, (3, 3), padding='same', use_bias=False, name='block13_sepconv2')(x)
  x = BatchNormalization(name='block13_sepconv2_bn')(x)

  x = MaxPooling2D(
      (3, 3), strides=(2, 2), padding='same', name='block13_pool')(x)
  x = layers.add([x, residual])

  x = SeparableConv2D(
      1536, (3, 3), padding='same', use_bias=False, name='block14_sepconv1')(x)
  x = BatchNormalization(name='block14_sepconv1_bn')(x)
  x = Activation('relu', name='block14_sepconv1_act')(x)

  x = SeparableConv2D(
      2048, (3, 3), padding='same', use_bias=False, name='block14_sepconv2')(x)
  x = BatchNormalization(name='block14_sepconv2_bn')(x)
  x = Activation('relu', name='block14_sepconv2_act')(x)

  if include_top:
    x = GlobalAveragePooling2D(name='avg_pool')(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input
  # Create model.
  model = Model(inputs, x, name='xception')

  # load weights
  if weights == 'imagenet':
    if include_top:
      weights_path = get_file(
          'xception_weights_tf_dim_ordering_tf_kernels.h5',
          TF_WEIGHTS_PATH,
          cache_subdir='models',
          file_hash='0a58e3b7378bc2990ea3b43d5981f1f6')
    else:
      weights_path = get_file(
          'xception_weights_tf_dim_ordering_tf_kernels_notop.h5',
          TF_WEIGHTS_PATH_NO_TOP,
          cache_subdir='models',
          file_hash='b0042744bf5b25fce3cb969f33bebb97')
    model.load_weights(weights_path)

  if old_data_format:
    K.set_image_data_format(old_data_format)
  elif weights is not None:
    model.load_weights(weights)
  return model
def ResNet50(include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000):
  """Instantiates the ResNet50 architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.

  The model and the weights are compatible with both
  TensorFlow and Theano. The data format
  convention used by the model is the one
  specified in your Keras config file.

  Arguments:
      include_top: whether to include the fully-connected
          layer at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or `(3, 224, 224)` (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 197.
          E.g. `(200, 200, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as imagenet with `include_top`'
                     ' as true, `classes` should be 1000')

  # Determine proper input shape
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=224,
      min_size=197,
      data_format=K.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor
  if K.image_data_format() == 'channels_last':
    bn_axis = 3
  else:
    bn_axis = 1

  x = Conv2D(
      64, (7, 7), strides=(2, 2), padding='same', name='conv1')(
          img_input)
  x = BatchNormalization(axis=bn_axis, name='bn_conv1')(x)
  x = Activation('relu')(x)
  x = MaxPooling2D((3, 3), strides=(2, 2))(x)

  x = conv_block(x, 3, [64, 64, 256], stage=2, block='a', strides=(1, 1))
  x = identity_block(x, 3, [64, 64, 256], stage=2, block='b')
  x = identity_block(x, 3, [64, 64, 256], stage=2, block='c')

  x = conv_block(x, 3, [128, 128, 512], stage=3, block='a')
  x = identity_block(x, 3, [128, 128, 512], stage=3, block='b')
  x = identity_block(x, 3, [128, 128, 512], stage=3, block='c')
  x = identity_block(x, 3, [128, 128, 512], stage=3, block='d')

  x = conv_block(x, 3, [256, 256, 1024], stage=4, block='a')
  x = identity_block(x, 3, [256, 256, 1024], stage=4, block='b')
  x = identity_block(x, 3, [256, 256, 1024], stage=4, block='c')
  x = identity_block(x, 3, [256, 256, 1024], stage=4, block='d')
  x = identity_block(x, 3, [256, 256, 1024], stage=4, block='e')
  x = identity_block(x, 3, [256, 256, 1024], stage=4, block='f')

  x = conv_block(x, 3, [512, 512, 2048], stage=5, block='a')
  x = identity_block(x, 3, [512, 512, 2048], stage=5, block='b')
  x = identity_block(x, 3, [512, 512, 2048], stage=5, block='c')

  x = AveragePooling2D((7, 7), name='avg_pool')(x)

  if include_top:
    x = Flatten()(x)
    x = Dense(classes, activation='softmax', name='fc1000')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input
  # Create model.
  model = Model(inputs, x, name='resnet50')

  # load weights
  if weights == 'imagenet':
    if include_top:
      weights_path = get_file(
          'resnet50_weights_tf_dim_ordering_tf_kernels.h5',
          WEIGHTS_PATH,
          cache_subdir='models',
          md5_hash='a7b3fe01876f51b976af0dea6bc144eb')
    else:
      weights_path = get_file(
          'resnet50_weights_tf_dim_ordering_tf_kernels_notop.h5',
          WEIGHTS_PATH_NO_TOP,
          cache_subdir='models',
          md5_hash='a268eb855778b3df3c7506639542a6af')
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)

  return model
Exemple #40
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def load_data(path='reuters.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              test_split=0.2,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3,
              **kwargs):
  """Loads the Reuters newswire classification dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: truncate sequences after this length.
      test_split: Fraction of the dataset to be used as test data.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.
      **kwargs: Used for backwards compatibility.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
  # Legacy support
  if 'nb_words' in kwargs:
    logging.warning('The `nb_words` argument in `load_data` '
                    'has been renamed `num_words`.')
    num_words = kwargs.pop('nb_words')
  if kwargs:
    raise TypeError('Unrecognized keyword arguments: ' + str(kwargs))

  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/reuters.npz',
      file_hash='87aedbeb0cb229e378797a632c1997b6')
  with np.load(path) as f:
    xs, labels = f['x'], f['y']

  np.random.seed(seed)
  indices = np.arange(len(xs))
  np.random.shuffle(indices)
  xs = xs[indices]
  labels = labels[indices]

  if start_char is not None:
    xs = [[start_char] + [w + index_from for w in x] for x in xs]
  elif index_from:
    xs = [[w + index_from for w in x] for x in xs]

  if maxlen:
    xs, labels = _remove_long_seq(maxlen, xs, labels)

  if not num_words:
    num_words = max([max(x) for x in xs])

  # by convention, use 2 as OOV word
  # reserve 'index_from' (=3 by default) characters:
  # 0 (padding), 1 (start), 2 (OOV)
  if oov_char is not None:
    xs = [[w if skip_top <= w < num_words else oov_char for w in x] for x in xs]
  else:
    xs = [[w for w in x if skip_top <= w < num_words] for x in xs]

  idx = int(len(xs) * (1 - test_split))
  x_train, y_train = np.array(xs[:idx]), np.array(labels[:idx])
  x_test, y_test = np.array(xs[idx:]), np.array(labels[idx:])

  return (x_train, y_train), (x_test, y_test)
Exemple #41
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    def load_data(self, path = 'imdb.npz',
                  num_words = None,
                  skip_top = 0,
                  maxlen = None,
                  seed = 113,
                  start_char = 1,
                  oov_char = 2,
                  index_from = 3):
        path = get_file(
            path,
            cache_subdir = path,
            origin = 'https://s3.amazonaws.com/text-datasets/imdb.npz',
            file_hash = '599dadb1135973df5b59232a0e9a887c')
        f = np.load(path)
        x_train, labels_train = f['x_train'], f['y_train']
        x_test, labels_test = f['x_test'], f['y_test']
        f.close()

        np.random.seed(seed)
        indices = np.arange(len(x_train))
        np.random.shuffle(indices)
        x_train = x_train[indices]
        labels_train = labels_train[indices]

        indices = np.arange(len(x_test))
        np.random.shuffle(indices)
        x_test = x_test[indices]
        labels_test = labels_test[indices]

        xs = np.concatenate([x_train, x_test])
        labels = np.concatenate([labels_train, labels_test])

        if start_char is not None:
            xs = [[start_char] + [w + index_from for w in x] for x in xs]
        elif index_from:
            xs = [[w + index_from for w in x] for x in xs]

        if maxlen:
            new_xs = []
            new_labels = []
            for x, y in zip(xs, labels):
                if len(x) < maxlen:
                    new_xs.append(x)
                    new_labels.append(y)
            xs = new_xs
            labels = new_labels
            if not xs:
                raise ValueError('After filtering for sequences shorter than maxlen=' +
                                 str(maxlen) + ', no sequence was kept. '
                                               'Increase maxlen.')
        if not num_words:
            num_words = max([max(x) for x in xs])

        # by convention, use 2 as OOV word
        # reserve 'index_from' (=3 by default) characters:
        # 0 (padding), 1 (start), 2 (OOV)
        if oov_char is not None:
            xs = [[oov_char if (w >= num_words or w < skip_top) else w for w in x]
                  for x in xs]
        else:
            new_xs = []
            for x in xs:
                nx = []
                for w in x:
                    if skip_top <= w < num_words:
                        nx.append(w)
                new_xs.append(nx)
            xs = new_xs

        x_train = np.array(xs[:len(x_train)])
        y_train = np.array(labels[:len(x_train)])

        x_test = np.array(xs[len(x_train):])
        y_test = np.array(labels[len(x_train):])
        return (x_train, y_train), (x_test, y_test)
Exemple #42
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def SENET50(include_top=True, weights='vggface',
            input_tensor=None, input_shape=None,
            pooling=None,
            classes=8631):
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=197,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor
    if K.image_data_format() == 'channels_last':
        bn_axis = 3
    else:
        bn_axis = 1

    x = Conv2D(
        64, (7, 7), use_bias=False, strides=(2, 2), padding='same',
        name='conv1/7x7_s2')(img_input)
    x = BatchNormalization(axis=bn_axis, name='conv1/7x7_s2/bn')(x)
    x = Activation('relu')(x)
    x = MaxPooling2D((3, 3), strides=(2, 2))(x)

    x = senet_conv_block(x, 3, [64, 64, 256], stage=2, block=1, strides=(1, 1))
    x = senet_identity_block(x, 3, [64, 64, 256], stage=2, block=2)
    x = senet_identity_block(x, 3, [64, 64, 256], stage=2, block=3)

    x = senet_conv_block(x, 3, [128, 128, 512], stage=3, block=1)
    x = senet_identity_block(x, 3, [128, 128, 512], stage=3, block=2)
    x = senet_identity_block(x, 3, [128, 128, 512], stage=3, block=3)
    x = senet_identity_block(x, 3, [128, 128, 512], stage=3, block=4)

    x = senet_conv_block(x, 3, [256, 256, 1024], stage=4, block=1)
    x = senet_identity_block(x, 3, [256, 256, 1024], stage=4, block=2)
    x = senet_identity_block(x, 3, [256, 256, 1024], stage=4, block=3)
    x = senet_identity_block(x, 3, [256, 256, 1024], stage=4, block=4)
    x = senet_identity_block(x, 3, [256, 256, 1024], stage=4, block=5)
    x = senet_identity_block(x, 3, [256, 256, 1024], stage=4, block=6)

    x = senet_conv_block(x, 3, [512, 512, 2048], stage=5, block=1)
    x = senet_identity_block(x, 3, [512, 512, 2048], stage=5, block=2)
    x = senet_identity_block(x, 3, [512, 512, 2048], stage=5, block=3)

    x = AveragePooling2D((7, 7), name='avg_pool')(x)

    if include_top:
        x = Flatten()(x)
        x = Dense(classes, activation='softmax', name='classifier')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input
    # Create model.
    model = Model(inputs, x, name='vggface_senet50')

    # load weights
    if weights == 'vggface':
        if include_top:
            weights_path = get_file('rcmalli_vggface_tf_senet50.h5',
                                    utils.SENET50_WEIGHTS_PATH,
                                    cache_subdir=utils.VGGFACE_DIR)
        else:
            weights_path = get_file('rcmalli_vggface_tf_notop_senet50.h5',
                                    utils.SENET50_WEIGHTS_PATH_NO_TOP,
                                    cache_subdir=utils.VGGFACE_DIR)
        model.load_weights(weights_path)
        if K.backend() == 'theano':
            layer_utils.convert_all_kernels_in_model(model)
            if include_top:
                maxpool = model.get_layer(name='avg_pool')
                shape = maxpool.output_shape[1:]
                dense = model.get_layer(name='classifier')
                layer_utils.convert_dense_weights_data_format(dense, shape,
                                                              'channels_first')

        if K.image_data_format() == 'channels_first' and K.backend() == 'tensorflow':
            warnings.warn('You are using the TensorFlow backend, yet you '
                          'are using the Theano '
                          'image data format convention '
                          '(`image_data_format="channels_first"`). '
                          'For best performance, set '
                          '`image_data_format="channels_last"` in '
                          'your Keras config '
                          'at ~/.keras/keras.json.')
    elif weights is not None:
        model.load_weights(weights)

    return model
Exemple #43
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def VGG16(include_top=True,
          weights='imagenet',
          input_tensor=None,
          input_shape=None,
          pooling=None,
          classes=1000):

    if weights not in {'imagenet', None}:
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization) or `imagenet` '
                         '(pre-training on ImageNet).')

    # Determine proper input shape
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=48,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        img_input = Input(tensor=input_tensor, shape=input_shape)

    # Block 1
    x = Conv2D(64, (3, 3),
               activation='relu',
               padding='same',
               name='block1_conv1')(img_input)
    x = Conv2D(64, (3, 3),
               activation='relu',
               padding='same',
               name='block1_conv2')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block1_pool')(x)

    # Block 2
    x = Conv2D(128, (3, 3),
               activation='relu',
               padding='same',
               name='block2_conv1')(x)
    x = Conv2D(128, (3, 3),
               activation='relu',
               padding='same',
               name='block2_conv2')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block2_pool')(x)

    # Block 3
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv1')(x)
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv2')(x)
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv3')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block3_pool')(x)

    # Block 4
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv1')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv2')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv3')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block4_pool')(x)

    # Block 5
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv1')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv2')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv3')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block5_pool')(x)

    if include_top:
        # Classification block
        x = Flatten(name='flatten')(x)
        x = Dense(4096, activation='relu', name='fc1')(x)
        x = Dropout(x, 0.5)
        x = Dense(4096, activation='relu', name='fc2')(x)
        x = Dropout(x, 0.5)
        x = Dense(classes, activation='softmax', name='predictions')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    model = Model(inputs, x, name='vgg16')

    # load weights
    if weights == 'imagenet':
        if include_top:
            weights_path = get_file(
                'vgg16_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models')
        else:
            weights_path = get_file(
                'vgg16_weights_tf_dim_ordering_tf_kernels_notop.h5',
                WEIGHTS_PATH_NO_TOP,
                cache_subdir='models')

        model.load_weights(weights_path)

        # Truncate and replace softmax layer for transfer learning
        model.layers.pop()
        model.outputs = [model.layers[-1].output]
        model.layers[-1].outbound_nodes = []
        model.add(Dense(5089, activation='softmax', name='predictions'))

        # Learning rate is changed to 0.001
        sgd = SGD(lr=1e-3, decay=1e-6, momentum=0.9, nesterov=True)
        model.compile(optimizer=sgd,
                      loss='categorical_crossentropy',
                      metrics=['accuracy'])
        """
    if K.backend() == 'theano':
      layer_utils.convert_all_kernels_in_model(model)

    if K.image_data_format() == 'channels_first':
      if include_top:
        maxpool = model.get_layer(name='block5_pool')
        shape = maxpool.output_shape[1:]
        dense = model.get_layer(name='fc1')
        layer_utils.convert_dense_weights_data_format(dense, shape,
                                                      'channels_first')
    """

    return model
Exemple #44
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def load_data(path='reuters.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              test_split=0.2,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3):
  """Loads the Reuters newswire classification dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: truncate sequences after this length.
      test_split: Fraction of the dataset to be used as test data.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
  path = get_file(
      path,
      origin='https://s3.amazonaws.com/text-datasets/reuters.npz',
      file_hash='87aedbeb0cb229e378797a632c1997b6')
  npzfile = np.load(path)
  xs = npzfile['x']
  labels = npzfile['y']
  npzfile.close()

  np.random.seed(seed)
  indices = np.arrange(len(xs))
  np.random.shuffle(indices)
  xs = xs[indices]
  labels = labels[indices]

  np.random.shuffle(labels)

  if start_char is not None:
    xs = [[start_char] + [w + index_from for w in x] for x in xs]
  elif index_from:
    xs = [[w + index_from for w in x] for x in xs]

  if maxlen:
    new_xs = []
    new_labels = []
    for x, y in zip(xs, labels):
      if len(x) < maxlen:
        new_xs.append(x)
        new_labels.append(y)
    xs = new_xs
    labels = new_labels

  if not num_words:
    num_words = max([max(x) for x in xs])

  # by convention, use 2 as OOV word
  # reserve 'index_from' (=3 by default) characters:
  # 0 (padding), 1 (start), 2 (OOV)
  if oov_char is not None:
    xs = [[oov_char if (w >= num_words or w < skip_top) else w for w in x]
          for x in xs]
  else:
    new_xs = []
    for x in xs:
      nx = []
      for w in x:
        if skip_top <= w < num_words:
          nx.append(w)
      new_xs.append(nx)
    xs = new_xs

  x_train = np.array(xs[:int(len(xs) * (1 - test_split))])
  y_train = np.array(labels[:int(len(xs) * (1 - test_split))])

  x_test = np.array(xs[int(len(xs) * (1 - test_split)):])
  y_test = np.array(labels[int(len(xs) * (1 - test_split)):])

  return (x_train, y_train), (x_test, y_test)
Exemple #45
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def NASNet(input_shape=None,
           penultimate_filters=4032,
           num_blocks=6,
           stem_block_filters=96,
           skip_reduction=True,
           filter_multiplier=2,
           include_top=True,
           weights=None,
           input_tensor=None,
           pooling=None,
           classes=1000,
           default_size=None):
  """Instantiates a NASNet model.

  Note that only TensorFlow is supported for now,
  therefore it only works with the data format
  `image_data_format='channels_last'` in your Keras config
  at `~/.keras/keras.json`.

  Arguments:
      input_shape: Optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(331, 331, 3)` for NASNetLarge or
          `(224, 224, 3)` for NASNetMobile
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 32.
          E.g. `(224, 224, 3)` would be one valid value.
      penultimate_filters: Number of filters in the penultimate layer.
          NASNet models use the notation `NASNet (N @ P)`, where:
              -   N is the number of blocks
              -   P is the number of penultimate filters
      num_blocks: Number of repeated blocks of the NASNet model.
          NASNet models use the notation `NASNet (N @ P)`, where:
              -   N is the number of blocks
              -   P is the number of penultimate filters
      stem_block_filters: Number of filters in the initial stem block
      skip_reduction: Whether to skip the reduction step at the tail
          end of the network. Set to `False` for CIFAR models.
      filter_multiplier: Controls the width of the network.
          - If `filter_multiplier` < 1.0, proportionally decreases the number
              of filters in each layer.
          - If `filter_multiplier` > 1.0, proportionally increases the number
              of filters in each layer.
          - If `filter_multiplier` = 1, default number of filters from the
               paper are used at each layer.
      include_top: Whether to include the fully-connected
          layer at the top of the network.
      weights: `None` (random initialization) or
          `imagenet` (ImageNet weights)
      input_tensor: Optional Keras tensor (i.e. output of
          `layers.Input()`)
          to use as image input for the model.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model
              will be the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a
              2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: Optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.
      default_size: Specifies the default image size of the model

  Returns:
      A Keras model instance.

  Raises:
      ValueError: In case of invalid argument for `weights`,
          invalid input shape or invalid `penultimate_filters` value.
      RuntimeError: If attempting to run this model with a
          backend that does not support separable convolutions.
  """
  if K.backend() != 'tensorflow':
    raise RuntimeError('Only Tensorflow backend is currently supported, '
                       'as other backends do not support '
                       'separable convolution.')

  if not (weights in {'imagenet', None} or os.path.exists(weights)):
    raise ValueError('The `weights` argument should be either '
                     '`None` (random initialization), `imagenet` '
                     '(pre-training on ImageNet), '
                     'or the path to the weights file to be loaded.')

  if weights == 'imagenet' and include_top and classes != 1000:
    raise ValueError('If using `weights` as ImageNet with `include_top` '
                     'as true, `classes` should be 1000')

  if default_size is None:
    default_size = 331

  # Determine proper input shape and default size.
  input_shape = _obtain_input_shape(
      input_shape,
      default_size=default_size,
      min_size=32,
      data_format=K.image_data_format(),
      require_flatten=include_top or weights,
      weights=weights)

  if K.image_data_format() != 'channels_last':
    logging.warning('The NASNet family of models is only available '
                    'for the input data format "channels_last" '
                    '(width, height, channels). '
                    'However your settings specify the default '
                    'data format "channels_first" (channels, width, height).'
                    ' You should set `image_data_format="channels_last"` '
                    'in your Keras config located at ~/.keras/keras.json. '
                    'The model being returned right now will expect inputs '
                    'to follow the "channels_last" data format.')
    K.set_image_data_format('channels_last')
    old_data_format = 'channels_first'
  else:
    old_data_format = None

  if input_tensor is None:
    img_input = Input(shape=input_shape)
  else:
    if not K.is_keras_tensor(input_tensor):
      img_input = Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor

  if penultimate_filters % 24 != 0:
    raise ValueError(
        'For NASNet-A models, the value of `penultimate_filters` '
        'needs to be divisible by 24. Current value: %d' % penultimate_filters)

  channel_dim = 1 if K.image_data_format() == 'channels_first' else -1
  filters = penultimate_filters // 24

  if not skip_reduction:
    x = Conv2D(
        stem_block_filters, (3, 3),
        strides=(2, 2),
        padding='valid',
        use_bias=False,
        name='stem_conv1',
        kernel_initializer='he_normal')(
            img_input)
  else:
    x = Conv2D(
        stem_block_filters, (3, 3),
        strides=(1, 1),
        padding='same',
        use_bias=False,
        name='stem_conv1',
        kernel_initializer='he_normal')(
            img_input)

  x = BatchNormalization(
      axis=channel_dim, momentum=0.9997, epsilon=1e-3, name='stem_bn1')(
          x)

  p = None
  if not skip_reduction:  # imagenet / mobile mode
    x, p = _reduction_a_cell(
        x, p, filters // (filter_multiplier**2), block_id='stem_1')
    x, p = _reduction_a_cell(
        x, p, filters // filter_multiplier, block_id='stem_2')

  for i in range(num_blocks):
    x, p = _normal_a_cell(x, p, filters, block_id='%d' % (i))

  x, p0 = _reduction_a_cell(
      x, p, filters * filter_multiplier, block_id='reduce_%d' % (num_blocks))

  p = p0 if not skip_reduction else p

  for i in range(num_blocks):
    x, p = _normal_a_cell(
        x, p, filters * filter_multiplier, block_id='%d' % (num_blocks + i + 1))

  x, p0 = _reduction_a_cell(
      x,
      p,
      filters * filter_multiplier**2,
      block_id='reduce_%d' % (2 * num_blocks))

  p = p0 if not skip_reduction else p

  for i in range(num_blocks):
    x, p = _normal_a_cell(
        x,
        p,
        filters * filter_multiplier**2,
        block_id='%d' % (2 * num_blocks + i + 1))

  x = Activation('relu')(x)

  if include_top:
    x = GlobalAveragePooling2D()(x)
    x = Dense(classes, activation='softmax', name='predictions')(x)
  else:
    if pooling == 'avg':
      x = GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = GlobalMaxPooling2D()(x)

  # Ensure that the model takes into account
  # any potential predecessors of `input_tensor`.
  if input_tensor is not None:
    inputs = get_source_inputs(input_tensor)
  else:
    inputs = img_input

  model = Model(inputs, x, name='NASNet')

  # load weights
  if weights == 'imagenet':
    if default_size == 224:  # mobile version
      if include_top:
        weight_path = NASNET_MOBILE_WEIGHT_PATH
        model_name = 'nasnet_mobile.h5'
      else:
        weight_path = NASNET_MOBILE_WEIGHT_PATH_NO_TOP
        model_name = 'nasnet_mobile_no_top.h5'

      weights_file = get_file(model_name, weight_path, cache_subdir='models')
      model.load_weights(weights_file)

    elif default_size == 331:  # large version
      if include_top:
        weight_path = NASNET_LARGE_WEIGHT_PATH
        model_name = 'nasnet_large.h5'
      else:
        weight_path = NASNET_LARGE_WEIGHT_PATH_NO_TOP
        model_name = 'nasnet_large_no_top.h5'

      weights_file = get_file(model_name, weight_path, cache_subdir='models')
      model.load_weights(weights_file)
    else:
      raise ValueError('ImageNet weights can only be loaded with NASNetLarge'
                       ' or NASNetMobile')
  elif weights is not None:
    model.load_weights(weights)

  if old_data_format:
    K.set_image_data_format(old_data_format)

  return model
Exemple #46
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def VGG19(include_top=True,
          weights='imagenet',
          input_tensor=None,
          input_shape=None,
          pooling=None,
          classes=1000):
    """Instantiates the VGG19 architecture.

  Optionally loads weights pre-trained
  on ImageNet. Note that when using TensorFlow,
  for best performance you should set
  `image_data_format='channels_last'` in your Keras config
  at ~/.keras/keras.json.

  The model and the weights are compatible with both
  TensorFlow and Theano. The data format
  convention used by the model is the one
  specified in your Keras config file.

  Arguments:
      include_top: whether to include the 3 fully-connected
          layers at the top of the network.
      weights: one of `None` (random initialization),
            'imagenet' (pre-training on ImageNet),
            or the path to the weights file to be loaded.
      input_tensor: optional Keras tensor (i.e. output of `layers.Input()`)
          to use as image input for the model.
      input_shape: optional shape tuple, only to be specified
          if `include_top` is False (otherwise the input shape
          has to be `(224, 224, 3)` (with `channels_last` data format)
          or `(3, 224, 224)` (with `channels_first` data format).
          It should have exactly 3 inputs channels,
          and width and height should be no smaller than 48.
          E.g. `(200, 200, 3)` would be one valid value.
      pooling: Optional pooling mode for feature extraction
          when `include_top` is `False`.
          - `None` means that the output of the model will be
              the 4D tensor output of the
              last convolutional layer.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional layer, and thus
              the output of the model will be a 2D tensor.
          - `max` means that global max pooling will
              be applied.
      classes: optional number of classes to classify images
          into, only to be specified if `include_top` is True, and
          if no `weights` argument is specified.

  Returns:
      A Keras model instance.

  Raises:
      ValueError: in case of invalid argument for `weights`,
          or invalid input shape.
  """
    if not (weights in {'imagenet', None} or os.path.exists(weights)):
        raise ValueError('The `weights` argument should be either '
                         '`None` (random initialization), `imagenet` '
                         '(pre-training on ImageNet), '
                         'or the path to the weights file to be loaded.')

    if weights == 'imagenet' and include_top and classes != 1000:
        raise ValueError('If using `weights` as imagenet with `include_top`'
                         ' as true, `classes` should be 1000')
    # Determine proper input shape
    input_shape = _obtain_input_shape(input_shape,
                                      default_size=224,
                                      min_size=48,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if input_tensor is None:
        img_input = Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor
    # Block 1
    x = Conv2D(64, (3, 3),
               activation='relu',
               padding='same',
               name='block1_conv1')(img_input)
    x = Conv2D(64, (3, 3),
               activation='relu',
               padding='same',
               name='block1_conv2')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block1_pool')(x)

    # Block 2
    x = Conv2D(128, (3, 3),
               activation='relu',
               padding='same',
               name='block2_conv1')(x)
    x = Conv2D(128, (3, 3),
               activation='relu',
               padding='same',
               name='block2_conv2')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block2_pool')(x)

    # Block 3
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv1')(x)
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv2')(x)
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv3')(x)
    x = Conv2D(256, (3, 3),
               activation='relu',
               padding='same',
               name='block3_conv4')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block3_pool')(x)

    # Block 4
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv1')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv2')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv3')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block4_conv4')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block4_pool')(x)

    # Block 5
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv1')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv2')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv3')(x)
    x = Conv2D(512, (3, 3),
               activation='relu',
               padding='same',
               name='block5_conv4')(x)
    x = MaxPooling2D((2, 2), strides=(2, 2), name='block5_pool')(x)

    if include_top:
        # Classification block
        x = Flatten(name='flatten')(x)
        x = Dense(4096, activation='relu', name='fc1')(x)
        x = Dense(4096, activation='relu', name='fc2')(x)
        x = Dense(classes, activation='softmax', name='predictions')(x)
    else:
        if pooling == 'avg':
            x = GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = GlobalMaxPooling2D()(x)

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = get_source_inputs(input_tensor)
    else:
        inputs = img_input
    # Create model.
    model = Model(inputs, x, name='vgg19')

    # load weights
    if weights == 'imagenet':
        if include_top:
            weights_path = get_file(
                'vgg19_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='cbe5617147190e668d6c5d5026f83318')
        else:
            weights_path = get_file(
                'vgg19_weights_tf_dim_ordering_tf_kernels_notop.h5',
                WEIGHTS_PATH_NO_TOP,
                cache_subdir='models',
                file_hash='253f8cb515780f3b799900260a226db6')
        model.load_weights(weights_path)
        if K.backend() == 'theano':
            layer_utils.convert_all_kernels_in_model(model)

        if K.image_data_format() == 'channels_first':
            if include_top:
                maxpool = model.get_layer(name='block5_pool')
                shape = maxpool.output_shape[1:]
                dense = model.get_layer(name='fc1')
                layer_utils.convert_dense_weights_data_format(
                    dense, shape, 'channels_first')

    elif weights is not None:
        model.load_weights(weights)

    return model
def load_data(path='imdb.npz',
              num_words=None,
              skip_top=0,
              maxlen=None,
              seed=113,
              start_char=1,
              oov_char=2,
              index_from=3,
              **kwargs):
    """Loads the IMDB dataset.

  Arguments:
      path: where to cache the data (relative to `~/.keras/dataset`).
      num_words: max number of words to include. Words are ranked
          by how often they occur (in the training set) and only
          the most frequent words are kept
      skip_top: skip the top N most frequently occurring words
          (which may not be informative).
      maxlen: sequences longer than this will be filtered out.
      seed: random seed for sample shuffling.
      start_char: The start of a sequence will be marked with this character.
          Set to 1 because 0 is usually the padding character.
      oov_char: words that were cut out because of the `num_words`
          or `skip_top` limit will be replaced with this character.
      index_from: index actual words with this index and higher.
      **kwargs: Used for backwards compatibility.

  Returns:
      Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.

  Raises:
      ValueError: in case `maxlen` is so low
          that no input sequence could be kept.

  Note that the 'out of vocabulary' character is only used for
  words that were present in the training set but are not included
  because they're not making the `num_words` cut here.
  Words that were not seen in the training set but are in the test set
  have simply been skipped.
  """
    # Legacy support
    if 'nb_words' in kwargs:
        logging.warning('The `nb_words` argument in `load_data` '
                        'has been renamed `num_words`.')
        num_words = kwargs.pop('nb_words')
    if kwargs:
        raise TypeError('Unrecognized keyword arguments: ' + str(kwargs))

    path = get_file(path,
                    origin='https://s3.amazonaws.com/text-datasets/imdb.npz',
                    file_hash='599dadb1135973df5b59232a0e9a887c')
    with np.load(path) as f:
        x_train, labels_train = f['x_train'], f['y_train']
        x_test, labels_test = f['x_test'], f['y_test']

    np.random.seed(seed)
    indices = np.arange(len(x_train))
    np.random.shuffle(indices)
    x_train = x_train[indices]
    labels_train = labels_train[indices]

    indices = np.arange(len(x_test))
    np.random.shuffle(indices)
    x_test = x_test[indices]
    labels_test = labels_test[indices]

    xs = np.concatenate([x_train, x_test])
    labels = np.concatenate([labels_train, labels_test])

    if start_char is not None:
        xs = [[start_char] + [w + index_from for w in x] for x in xs]
    elif index_from:
        xs = [[w + index_from for w in x] for x in xs]

    if maxlen:
        xs, labels = _remove_long_seq(maxlen, xs, labels)
        if not xs:
            raise ValueError(
                'After filtering for sequences shorter than maxlen=' +
                str(maxlen) + ', no sequence was kept. '
                'Increase maxlen.')
    if not num_words:
        num_words = max([max(x) for x in xs])

    # by convention, use 2 as OOV word
    # reserve 'index_from' (=3 by default) characters:
    # 0 (padding), 1 (start), 2 (OOV)
    if oov_char is not None:
        xs = [[w if (skip_top <= w < num_words) else oov_char for w in x]
              for x in xs]
    else:
        xs = [[w for w in x if skip_top <= w < num_words] for x in xs]

    idx = len(x_train)
    x_train, y_train = np.array(xs[:idx]), np.array(labels[:idx])
    x_test, y_test = np.array(xs[idx:]), np.array(labels[idx:])

    return (x_train, y_train), (x_test, y_test)