示例#1
0
def ResNet50(input_tensor=None,
             pooling=None,
             **kwargs):
    """Instantiates the ResNet50 architecture.
    # Arguments       
    # Returns
        A Keras model instance.
    """
    # Input arguments
    include_top = get_varargin(kwargs, 'include_top', True)
    nb_classes = get_varargin(kwargs, 'nb_classes', 1000)
    default_input_shape = _obtain_input_shape(None,
                                      default_size=224,
                                      min_size=197,
                                      data_format=K.image_data_format(),
                                      require_flatten=include_top)
    input_shape = get_varargin(kwargs, 'input_shape', default_input_shape)
    if input_tensor is None:
        img_input = KL.Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = KL.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 = KL.ZeroPadding2D((3, 3))(img_input)
    x = KL.Conv2D(64, (7, 7), strides=(2, 2), name='conv1')(x)
    x = KL.BatchNormalization(axis=bn_axis, name='bn_conv1')(x)
    x = KL.Activation('relu')(x)
    x = KL.MaxPooling2D((3, 3), strides=(2, 2))(x)
    
    for stage, nb_block in zip([2,3,4,5], [3,4,6,3]):
        for blk in range(nb_block):
            conv_block = True if blk == 0 else False
            strides = (2,2) if stage>2 and blk==0 else (1,1)           
            x = identity_block(x, stage = stage, block_id = blk + 1,
                               conv_block = conv_block, strides = strides)
            
    x = KL.AveragePooling2D((7, 7), name='avg_pool')(x)

    if include_top:
        x = KL.Flatten()(x)
        x = KL.Dense(nb_classes, activation='softmax', name='fc1000')(x)
    else:
        if pooling == 'avg':
            x = KL.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = KL.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')
    return model
示例#2
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    def assemble_layers(self):
        from tensorflow.python.keras import backend, layers
        from tensorflow.python.keras.applications import imagenet_utils

        include_top = True
        weights = None
        pooling = None
        classes = 1
        if nnstate.FLAGS.PRED_SIZE != 2:
            err('bad')
        classifier_activation = 'sigmoid'

        x = conv2d_bn(self.inputs, 32, 3, strides=2, padding='valid')
        x = conv2d_bn(x, 32, 3, padding='valid')
        x = conv2d_bn(x, 64, 3)
        x = layers.MaxPooling2D(3, strides=2)(x)
        x = conv2d_bn(x, 80, 1, padding='valid')
        x = conv2d_bn(x, 192, 3, padding='valid')
        x = layers.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 = layers.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 backend.image_data_format(
        ) == 'channels_first' else 3
        x = layers.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 = layers.MaxPooling2D(3, strides=2, padding='valid')(x)
        branches = [branch_0, branch_1, branch_pool]
        x = layers.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 = layers.MaxPooling2D(3, strides=2, padding='valid')(x)
        branches = [branch_0, branch_1, branch_2, branch_pool]
        x = layers.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 = layers.GlobalAveragePooling2D(name='avg_pool')(x)
            imagenet_utils.validate_activation(classifier_activation, weights)
            x = layers.Dense(classes,
                             activation=classifier_activation,
                             name='predictions')(x)
        else:
            if pooling == 'avg':
                x = layers.GlobalAveragePooling2D()(x)
            elif pooling == 'max':
                x = layers.GlobalMaxPooling2D()(x)

        return x
示例#3
0
def Xception(
    include_top=True,
    weights='imagenet',
    input_tensor=None,
    input_shape=None,
    pooling=None,
    classes=1000,
    classifier_activation='softmax',
):
    """Instantiates the Xception architecture.

  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.
  Note that the default input image size for this model is 299x299.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.xception.preprocess_input` for an example.

  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 block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=299,
        min_size=71,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

    channel_axis = 1 if backend.image_data_format() == 'channels_first' else -1

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            weights_path = data_utils.get_file(
                'xception_weights_tf_dim_ordering_tf_kernels.h5',
                TF_WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='0a58e3b7378bc2990ea3b43d5981f1f6')
        else:
            weights_path = data_utils.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)

    return model
示例#4
0
def EfficientNet(width_coefficient,
                 depth_coefficient,
                 default_size,
                 dropout_rate=0.2,
                 drop_connect_rate=0.2,
                 depth_divisor=8,
                 activation='swish',
                 blocks_args='default',
                 model_name='efficientnet',
                 include_top=True,
                 weights='imagenet',
                 input_tensor=None,
                 input_shape=None,
                 pooling=None,
                 classes=1000):
  """Instantiates the EfficientNet architecture using given scaling coefficients.

  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.

  Arguments:
    width_coefficient: float, scaling coefficient for network width.
    depth_coefficient: float, scaling coefficient for network depth.
    default_size: integer, default input image size.
    dropout_rate: float, dropout rate before final classifier layer.
    drop_connect_rate: float, dropout rate at skip connections.
    depth_divisor: integer, a unit of network width.
    activation: activation function.
    blocks_args: list of dicts, parameters to construct block modules.
    model_name: string, model name.
    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.
        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 blocks_args == 'default':
    blocks_args = DEFAULT_BLOCKS_ARGS

  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 = imagenet_utils.obtain_input_shape(
      input_shape,
      default_size=default_size,
      min_size=32,
      data_format=backend.image_data_format(),
      require_flatten=include_top,
      weights=weights)

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

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

  def round_filters(filters, divisor=depth_divisor):
    """Round number of filters based on depth multiplier."""
    filters *= width_coefficient
    new_filters = max(divisor, int(filters + divisor / 2) // divisor * divisor)
    # Make sure that round down does not go down by more than 10%.
    if new_filters < 0.9 * filters:
      new_filters += divisor
    return int(new_filters)

  def round_repeats(repeats):
    """Round number of repeats based on depth multiplier."""
    return int(math.ceil(depth_coefficient * repeats))

  # Build stem
  x = img_input
  x = layers.Rescaling(1. / 255.)(x)
  x = layers.Normalization(axis=bn_axis)(x)

  x = layers.ZeroPadding2D(
      padding=imagenet_utils.correct_pad(x, 3),
      name='stem_conv_pad')(x)
  x = layers.Conv2D(
      round_filters(32),
      3,
      strides=2,
      padding='valid',
      use_bias=False,
      kernel_initializer=CONV_KERNEL_INITIALIZER,
      name='stem_conv')(x)
  x = layers.BatchNormalization(axis=bn_axis, name='stem_bn')(x)
  x = layers.Activation(activation, name='stem_activation')(x)

  # Build blocks
  blocks_args = copy.deepcopy(blocks_args)

  b = 0
  blocks = float(sum(args['repeats'] for args in blocks_args))
  for (i, args) in enumerate(blocks_args):
    assert args['repeats'] > 0
    # Update block input and output filters based on depth multiplier.
    args['filters_in'] = round_filters(args['filters_in'])
    args['filters_out'] = round_filters(args['filters_out'])

    for j in range(round_repeats(args.pop('repeats'))):
      # The first block needs to take care of stride and filter size increase.
      if j > 0:
        args['strides'] = 1
        args['filters_in'] = args['filters_out']
      x = block(
          x,
          activation,
          drop_connect_rate * b / blocks,
          name='block{}{}_'.format(i + 1, chr(j + 97)),
          **args)
      b += 1

  # Build top
  x = layers.Conv2D(
      round_filters(1280),
      1,
      padding='same',
      use_bias=False,
      kernel_initializer=CONV_KERNEL_INITIALIZER,
      name='top_conv')(x)
  x = layers.BatchNormalization(axis=bn_axis, name='top_bn')(x)
  x = layers.Activation(activation, name='top_activation')(x)
  if include_top:
    x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    if dropout_rate > 0:
      x = layers.Dropout(dropout_rate, name='top_dropout')(x)
    x = layers.Dense(
        classes,
        activation='softmax',
        kernel_initializer=DENSE_KERNEL_INITIALIZER,
        name='probs')(x)
  else:
    if pooling == 'avg':
      x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    elif pooling == 'max':
      x = layers.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 = layer_utils.get_source_inputs(input_tensor)
  else:
    inputs = img_input

  # Create model.
  model = training.Model(inputs, x, name=model_name)

  # Load weights.
  if weights == 'imagenet':
    if include_top:
      file_suffix = '.h5'
      file_hash = WEIGHTS_HASHES[model_name[-2:]][0]
    else:
      file_suffix = '_notop.h5'
      file_hash = WEIGHTS_HASHES[model_name[-2:]][1]
    file_name = model_name + file_suffix
    weights_path = data_utils.get_file(
        file_name,
        BASE_WEIGHTS_PATH + file_name,
        cache_subdir='models',
        file_hash=file_hash)
    model.load_weights(weights_path)
  elif weights is not None:
    model.load_weights(weights)
  return model
示例#5
0
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,
    classifier_activation='softmax',
):
    """Instantiates a NASNet model.

  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.nasnet.preprocess_input` for an example.

  Arguments:
    input_shape: Optional shape tuple, the input shape
      is by default `(331, 331, 3)` for NASNetLarge and
      `(224, 224, 3)` for NASNetMobile.
      It should have exactly 3 input 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.
    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 block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: In case of invalid argument for `weights`,
      invalid input shape or invalid `penultimate_filters` value.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    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 (isinstance(input_shape, tuple) and None in input_shape
            and weights == 'imagenet'):
        raise ValueError('When specifying the input shape of a NASNet'
                         ' and loading `ImageNet` weights, '
                         'the input_shape argument must be static '
                         '(no None entries). Got: `input_shape=' +
                         str(input_shape) + '`.')

    if default_size is None:
        default_size = 331

    # Determine proper input shape and default size.
    input_shape = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=default_size,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=True,
        weights=weights)

    if backend.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.')
        backend.set_image_data_format('channels_last')
        old_data_format = 'channels_first'
    else:
        old_data_format = None

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

    if penultimate_filters % (24 * (filter_multiplier**2)) != 0:
        raise ValueError(
            'For NASNet-A models, the `penultimate_filters` must be a multiple '
            'of 24 * (`filter_multiplier` ** 2). Current value: %d' %
            penultimate_filters)

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

    x = layers.Conv2D(stem_block_filters, (3, 3),
                      strides=(2, 2),
                      padding='valid',
                      use_bias=False,
                      name='stem_conv1',
                      kernel_initializer='he_normal')(img_input)

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

    p = None
    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 = layers.Activation('relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D()(x)
        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

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

    # Load weights.
    if weights == 'imagenet':
        if default_size == 224:  # mobile version
            if include_top:
                weights_path = data_utils.get_file(
                    'nasnet_mobile.h5',
                    NASNET_MOBILE_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='020fb642bf7360b370c678b08e0adf61')
            else:
                weights_path = data_utils.get_file(
                    'nasnet_mobile_no_top.h5',
                    NASNET_MOBILE_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='1ed92395b5b598bdda52abe5c0dbfd63')
            model.load_weights(weights_path)
        elif default_size == 331:  # large version
            if include_top:
                weights_path = data_utils.get_file(
                    'nasnet_large.h5',
                    NASNET_LARGE_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='11577c9a518f0070763c2b964a382f17')
            else:
                weights_path = data_utils.get_file(
                    'nasnet_large_no_top.h5',
                    NASNET_LARGE_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='d81d89dc07e6e56530c4e77faddd61b5')
            model.load_weights(weights_path)
        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:
        backend.set_image_data_format(old_data_format)

    return model
示例#6
0
def MobileNetV3(stack_fn,
                last_point_ch,
                input_shape=None,
                alpha=1.0,
                model_type='large',
                minimalistic=False,
                include_top=True,
                weights='imagenet',
                input_tensor=None,
                classes=1000,
                pooling=None,
                dropout_rate=0.2,
                classifier_activation='softmax'):
    if not (weights in {'imagenet', None} or file_io.file_exists_v2(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 both input_shape and input_tensor are used, they should match
    if input_shape is not None and input_tensor is not None:
        try:
            is_input_t_tensor = backend.is_keras_tensor(input_tensor)
        except ValueError:
            try:
                is_input_t_tensor = backend.is_keras_tensor(
                    layer_utils.get_source_inputs(input_tensor))
            except ValueError:
                raise ValueError('input_tensor: ', input_tensor,
                                 'is not type input_tensor')
        if is_input_t_tensor:
            if backend.image_data_format == 'channels_first':
                if backend.int_shape(input_tensor)[1] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
            else:
                if backend.int_shape(input_tensor)[2] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
        else:
            raise ValueError('input_tensor specified: ', input_tensor,
                             'is not a keras tensor')

    # If input_shape is None, infer shape from input_tensor
    if input_shape is None and input_tensor is not None:

        try:
            backend.is_keras_tensor(input_tensor)
        except ValueError:
            raise ValueError('input_tensor: ', input_tensor, 'is type: ',
                             type(input_tensor), 'which is not a valid type')

        if backend.is_keras_tensor(input_tensor):
            if backend.image_data_format() == 'channels_first':
                rows = backend.int_shape(input_tensor)[2]
                cols = backend.int_shape(input_tensor)[3]
                input_shape = (3, cols, rows)
            else:
                rows = backend.int_shape(input_tensor)[1]
                cols = backend.int_shape(input_tensor)[2]
                input_shape = (cols, rows, 3)
    # If input_shape is None and input_tensor is None using standart shape
    if input_shape is None and input_tensor is None:
        input_shape = (None, None, 3)

    if backend.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 rows and cols and (rows < 32 or cols < 32):
        raise ValueError(
            'Input size must be at least 32x32; got `input_shape=' +
            str(input_shape) + '`')
    if weights == 'imagenet':
        if (not minimalistic and alpha not in [0.75, 1.0]
                or minimalistic and alpha != 1.0):
            raise ValueError(
                'If imagenet weights are being loaded, '
                'alpha can be one of `0.75`, `1.0` for non minimalistic'
                ' or `1.0` for minimalistic only.')

        if rows != cols or rows != 224:
            logging.warning('`input_shape` is undefined or non-square, '
                            'or `rows` is not 224.'
                            ' Weights for input shape (224, 224) will be'
                            ' loaded as the default.')

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

    channel_axis = 1 if backend.image_data_format() == 'channels_first' else -1

    if minimalistic:
        kernel = 3
        activation = relu
        se_ratio = None
    else:
        kernel = 5
        activation = hard_swish
        se_ratio = 0.25

    x = img_input
    x = layers.Rescaling(1. / 255.)(x)
    x = layers.Conv2D(16,
                      kernel_size=3,
                      strides=(2, 2),
                      padding='same',
                      use_bias=False,
                      name='Conv')(x)
    x = layers.BatchNormalization(axis=channel_axis,
                                  epsilon=1e-3,
                                  momentum=0.999,
                                  name='Conv/BatchNorm')(x)
    x = activation(x)

    x = stack_fn(x, kernel, activation, se_ratio)

    last_conv_ch = _depth(backend.int_shape(x)[channel_axis] * 6)

    # if the width multiplier is greater than 1 we
    # increase the number of output channels
    if alpha > 1.0:
        last_point_ch = _depth(last_point_ch * alpha)
    x = layers.Conv2D(last_conv_ch,
                      kernel_size=1,
                      padding='same',
                      use_bias=False,
                      name='Conv_1')(x)
    x = layers.BatchNormalization(axis=channel_axis,
                                  epsilon=1e-3,
                                  momentum=0.999,
                                  name='Conv_1/BatchNorm')(x)
    x = activation(x)
    x = layers.Conv2D(last_point_ch,
                      kernel_size=1,
                      padding='same',
                      use_bias=True,
                      name='Conv_2')(x)
    x = activation(x)

    if include_top:
        x = layers.GlobalAveragePooling2D()(x)
        if channel_axis == 1:
            x = layers.Reshape((last_point_ch, 1, 1))(x)
        else:
            x = layers.Reshape((1, 1, last_point_ch))(x)
        if dropout_rate > 0:
            x = layers.Dropout(dropout_rate)(x)
        x = layers.Conv2D(classes,
                          kernel_size=1,
                          padding='same',
                          name='Logits')(x)
        x = layers.Flatten()(x)
        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Activation(activation=classifier_activation,
                              name='Predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    model = models.Model(inputs, x, name='MobilenetV3' + model_type)

    # Load weights.
    if weights == 'imagenet':
        model_name = '{}{}_224_{}_float'.format(
            model_type, '_minimalistic' if minimalistic else '', str(alpha))
        if include_top:
            file_name = 'weights_mobilenet_v3_' + model_name + '.h5'
            file_hash = WEIGHTS_HASHES[model_name][0]
        else:
            file_name = 'weights_mobilenet_v3_' + model_name + '_no_top.h5'
            file_hash = WEIGHTS_HASHES[model_name][1]
        weights_path = data_utils.get_file(file_name,
                                           BASE_WEIGHT_PATH + file_name,
                                           cache_subdir='models',
                                           file_hash=file_hash)
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
示例#7
0
def VGG16(include_top=True,
          weights='imagenet',
          input_tensor=None,
          input_shape=None,
          pooling=None,
          classes=1000):
    """Instantiates the VGG16 model.

  By default, it loads weights pre-trained on ImageNet. Check 'weights' for
  other options.

  This model can be built both with 'channels_first' data format
  (channels, height, width) or 'channels_last' data format
  (height, width, channels).

  The default input size for this model is 224x224.

  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 input channels,
          and width and height should be no smaller than 32.
          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 block.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional block, 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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=224,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

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

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

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

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

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

    # Ensure that the model takes into account
    # any potential predecessors of `input_tensor`.
    if input_tensor is not None:
        inputs = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input
    # Create model.
    model = training.Model(inputs, x, name='vgg16')

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            weights_path = data_utils.get_file(
                'vgg16_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='64373286793e3c8b2b4e3219cbf3544b')
        else:
            weights_path = data_utils.get_file(
                'vgg16_weights_tf_dim_ordering_tf_kernels_notop.h5',
                WEIGHTS_PATH_NO_TOP,
                cache_subdir='models',
                file_hash='6d6bbae143d832006294945121d1f1fc')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
示例#8
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def WideResNet(
    stack_fn,
    preact=True,
    model_name='resnet',
    head='one_head',
    head_mlp='',
    input_shape=None,
    pooling=None,
    activation='leaky_relu',
    bn_sync=BN_SYNC,
    num_class=1000,
    **kwargs):

    # Input layer.
    inputs = img_input = layers.Input(shape=input_shape)

    # Conv1 block.
    # CIFAR (32x32) or STL-10 (96x96) use small input; otherwise use large input
    if input_shape[0] == 256:
        kernel_size, stride, maxpool = 7, 2, True
    elif input_shape[0] in [96, 128]:
        kernel_size, stride, maxpool = 3, 1, False
    elif input_shape[0] == 32:
        kernel_size, stride, maxpool = 3, 1, False
    else:
        raise NotImplementedError
    x = convnxn(img_input, filters=16, kernel_size=kernel_size,
        strides=stride, use_bias=False,
        name='conv1_conv')
    if not preact:
        x = batchnorm(x, bn_mom=0.999, bn_eps=0.001, bn_sync=bn_sync, name='conv1_bn')
        x = nonlinearity(x, layer_activation=activation, name='conv1_'+activation)
    if maxpool:
        x = layers.MaxPooling2D(3, strides=2, padding='SAME',
            name='pool1_pool')(x)

    # Conv2 to Conv5 blocks
    x = stack_fn(x)
    if preact:
        x = batchnorm(x, bn_mom=0.999, bn_eps=0.001, bn_sync=bn_sync, name='post_bn')
        x = nonlinearity(x, layer_activation=activation, name='post_'+activation)

    # Pooling layer
    if pooling in ['avg', None]:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    elif pooling == 'max':
        x = layers.GlobalMaxPooling2D(name='max_pool')(x)

    # Classifier and/or embedding head
    outputs = get_head(
        x, arch=head, dims=head_mlp, num_class=num_class,
        bn_mom=0.999, bn_eps=0.001, bn_sync=bn_sync,
        classifier_activation='linear')

    # Create model.
    if bn_sync:
        model_name += '_sbn'
    if not head in ['linear', None, False]:
        model_name += '_{}'.format(head)
        if head_mlp is not None and len(head_mlp) > 0:
            model_name += '_mlp' + '_'.join(['%d'%d for d in head_mlp])
    return training.Model(inputs, outputs, name=model_name)
示例#9
0
def MobileNetV2(input_shape=None,
                alpha=1.0,
                include_top=True,
                input_tensor=None,
                pooling=None,
                classes=1000):
    """Instantiates the MobileNetV2 architecture.

  Args:
      input_shape: optional shape tuple, to be specified if you would
          like to use a model with an input img resolution that is not
          (224, 224, 3).
          It should have exactly 3 inputs channels (224, 224, 3).
          You can also omit this option if you would like
          to infer input_shape from an input_tensor.
          If you choose to include both input_tensor and input_shape then
          input_shape will be used if they match, if the shapes
          do not match then we will throw an error.
          E.g. `(160, 160, 3)` would be one valid value.
      alpha: controls the width of the network. This is known as the
      width multiplier in the MobileNetV2 paper, but the name is kept for
      consistency with MobileNetV1 in Keras.
          - 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.
      include_top: whether to include the fully-connected
          layer at the top of the network.
      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 block.
          - `avg` means that global average pooling
              will be applied to the output of the
              last convolutional block, 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 or invalid alpha, rows when
          weights='imagenet'
  """
    if classes == 1000:
        raise ValueError('If use dataset is `imagenet`, please use it,'
                         'otherwise please use classifier images classes.')

    if input_shape == (32, 32, 1):
        raise ValueError(
            'If use input shape is `32 * 32 * 1`, please don`t use it! '
            'So you should change network architecture '
            'or use input shape is `224 * 224 * 3`.')

    # Determine proper input shape and default size.
    # If both input_shape and input_tensor are used, they should match
    if input_shape is not None and input_tensor is not None:
        try:
            is_input_t_tensor = backend.is_keras_tensor(input_tensor)
        except ValueError:
            try:
                is_input_t_tensor = backend.is_keras_tensor(
                    utils.get_source_inputs(input_tensor))
            except ValueError:
                raise ValueError('input_tensor: ', input_tensor,
                                 'is not type input_tensor')
        if is_input_t_tensor:
            if backend.image_data_format == 'channels_first':
                if backend.int_shape(input_tensor)[1] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
            else:
                if backend.int_shape(input_tensor)[2] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
        else:
            raise ValueError('input_tensor specified: ', input_tensor,
                             'is not a keras tensor')

    # If input_shape is None, infer shape from input_tensor
    if input_shape is None and input_tensor is not None:

        try:
            backend.is_keras_tensor(input_tensor)
        except ValueError:
            raise ValueError('input_tensor: ', input_tensor, 'is type: ',
                             type(input_tensor), 'which is not a valid type')

        if input_shape is None and not backend.is_keras_tensor(input_tensor):
            pass
        elif input_shape is None and backend.is_keras_tensor(input_tensor):
            if backend.image_data_format() == 'channels_first':
                rows = backend.int_shape(input_tensor)[2]
                cols = backend.int_shape(input_tensor)[3]
            else:
                rows = backend.int_shape(input_tensor)[1]
                cols = backend.int_shape(input_tensor)[2]

            if rows == cols and rows in [96, 128, 160, 192, 224]:
                pass
            else:
                pass

    # If input_shape is None and no input_tensor
    elif input_shape is None:
        pass

    # If input_shape is not None, assume default size
    else:
        if backend.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 [96, 128, 160, 192, 224]:
            pass
        else:
            pass

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

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

    first_block_filters = _make_divisible(32 * alpha, 8)
    x = layers.ZeroPadding2D(padding=correct_pad(backend, img_input, 3),
                             name='Conv1_pad')(img_input)
    x = layers.Conv2D(first_block_filters,
                      kernel_size=3,
                      strides=(2, 2),
                      padding='valid',
                      use_bias=False,
                      name='Conv1')(x)
    x = layers.BatchNormalization(epsilon=1e-3,
                                  momentum=0.999,
                                  name='bn_Conv1')(x)
    x = layers.ReLU(6., name='Conv1_relu')(x)

    x = _inverted_res_block(x,
                            filters=16,
                            alpha=alpha,
                            stride=1,
                            expansion=1,
                            block_id=0)

    x = _inverted_res_block(x,
                            filters=24,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=1)
    x = _inverted_res_block(x,
                            filters=24,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=2)

    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=3)
    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=4)
    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=5)

    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=6)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=7)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=8)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=9)

    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=10)
    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=11)
    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=12)

    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=13)
    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=14)
    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=15)

    x = _inverted_res_block(x,
                            filters=320,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=16)

    # no alpha applied to last conv as stated in the paper:
    # if the width multiplier is greater than 1 we
    # increase the number of output channels
    if alpha > 1.0:
        last_block_filters = _make_divisible(1280 * alpha, 8)
    else:
        last_block_filters = 1280

    x = layers.Conv2D(last_block_filters,
                      kernel_size=1,
                      use_bias=False,
                      name='Conv_1')(x)
    x = layers.BatchNormalization(epsilon=1e-3,
                                  momentum=0.999,
                                  name='Conv_1_bn')(x)
    x = layers.ReLU(6., name='out_relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D()(x)
        x = layers.Dense(classes,
                         activation='softmax',
                         use_bias=True,
                         name='Logits')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

    # Create model.
    model = models.Model(inputs,
                         x,
                         name='mobilenetv2_%0.2f_%s' % (alpha, rows))

    return model
示例#10
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def efficientnetB0(width_coeff=1,
                   depth_coeff=1,
                   default_img_size=224,
                   dropoutrate=0.2,
                   drop_connect_rate=0.2,
                   depth_divisor=8,
                   activations='swish',
                   block_args='default',
                   include_top=True,
                   weights='imagenet',
                   input_tensor=None,
                   input_shape=None,
                   pooling=None,
                   classes=1000,
                   classifier_activation='softmax'):

    if block_args == 'default':
        block_args = DEFAULT_BLOCKS_ARGS

    if not (weights in {'imagenet', None} or file_io.file_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')

    # proper input shape check

    input_shape = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=default_img_size,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

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

    def round_filters(filters, divisor=depth_divisor):
        """ round number of filters based on depth multiplier"""
        filters *= width_coeff
        new_filters = max(divisor,
                          int(filters + divisor / 2) // divisor * divisor)
        #making sure round down does not go down by 10%
        if new_filters < 0.9 * filters:
            new_filters += divisor
        return int(new_filters)

    def round_repeats(repeats):
        """Round number of repeats based on depth multiplier."""
        return int(math.ceil(depth_coeff * repeats))

    #building stem

    x = img_input
    x = layers.Rescaling(1. / 255.)(x)
    x = layers.Normalization(axis=bn_axis)(x)

    x = layers.ZeroPadding2D(padding=imagenet_utils.correct_pad(x, 3))(x)
    x = layers.Conv2D(round_filters(32),
                      kernel_size=3,
                      strides=2,
                      padding='valid',
                      use_bias=False,
                      kernel_initializer=CONV_KERNEL_INITIALIZER)(x)

    x = layers.BatchNormalization(axis=bn_axis)(x)
    x = layers.Activation(activations)(x)

    #building blocks
    block_args = copy.deepcopy(block_args)

    b = 0
    blocks = float(sum(round_repeats(args['repeats']) for args in block_args))

    for (i, args) in enumerate(block_args):
        assert args['repeats'] > 0

        args['filters_in'] = round_filters(args['filters_in'])
        args['filters_out'] = round_filters(args['filters_out'])

        for j in range(round_repeats(args.pop('repeats'))):
            # The first block needs to take care of stride and filter size increase.
            if j > 0:
                args['strides'] = 1
                args['filters_in'] = args['filters_out']

            x = mbconvblock(inputs=x,
                            activations=activations,
                            droprate=drop_connect_rate * b / blocks,
                            name=str(i),
                            **args)
            b += 1

    #build top

    x = layers.Conv2D(round_filters(1280),
                      kernel_size=1,
                      padding='same',
                      use_bias=False,
                      kernel_initializer=CONV_KERNEL_INITIALIZER)(x)

    x = layers.BatchNormalization(axis=bn_axis)(x)
    x = layers.Activation(activations)(x)

    if include_top:
        x = layers.GlobalAveragePooling2D()(x)
        if dropoutrate > 0:
            x = layers.Dropout(dropoutrate)(x)
        imagenet_utils.validate_activation(classifier_activation, weights)

        x = layers.Dense(classes,
                         activation=classifier_activation,
                         kernel_initializer=DENSE_KERNEL_INITIALIZER)(x)

    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

    #creating model
    model = training.Model(inputs, x)

    return model
示例#11
0
def DenseNet(blocks,
             classes,
             filters,
             dropout_rate,
             include_top=True,
             weights=None,
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classifier_activation=None):
    # Determine proper input shape
    if input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not backend.is_keras_tensor(input_tensor):
            img_input = layers.Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

    # x = layers.ZeroPadding2D(padding=((3, 3), (3, 3)))(x)
    x = layers.Conv2D(2 * filters,
                      3,
                      strides=2,
                      padding='same',
                      name='conv1/conv')(img_input)
    # x = layers.BatchNormalization(axis=bn_axis,
    #                               epsilon=1.001e-5,
    #                               name='conv1/bn')(x)
    # x = layers.Activation('relu', name='conv1/relu')(x)
    # x = layers.ZeroPadding2D(padding=((1, 1), (1, 1)))(x)
    x = layers.MaxPooling2D(pool_size=(3, 3), strides=2, name='pool1')(x)

    # x = dense_block(x,
    #                 blocks=6,
    #                 filters=filters,
    #                 dropout_rate=dropout_rate,
    #                 name='dense_1')
    # x = transition_block(x, dropout_rate=dropout_rate, name='trans_2')
    # x = dense_block(x,
    #                 blocks=12,
    #                 filters=filters,
    #                 dropout_rate=dropout_rate,
    #                 name='dense_2')
    # x = transition_block(x, dropout_rate=dropout_rate, name='trans_3')
    # x = dense_block(x,
    #                 blocks=24,
    #                 filters=filters,
    #                 dropout_rate=dropout_rate,
    #                 name='dense_3')
    # x = transition_block(x, dropout_rate=dropout_rate, name='trans_4')
    # x = dense_block(x,
    #                 blocks=16,
    #                 filters=filters,
    #                 dropout_rate=dropout_rate,
    #                 name='dense_4')

    for i in range(blocks):
        x = dense_block(x,
                        blocks=6,
                        filters=filters,
                        dropout_rate=dropout_rate,
                        name='dense_' + str(i))
        x = transition_block(x,
                             dropout_rate=dropout_rate,
                             name='trans_' + str(i))
    x = dense_block(x,
                    blocks=12,
                    filters=filters,
                    dropout_rate=dropout_rate,
                    name='dense_final')

    x = layers.BatchNormalization()(x)
    x = layers.Activation('relu', name='relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        x = layers.Flatten()(x)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

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

    return model
示例#12
0
def VGG19(
    include_top=True,
    weights='imagenet',
    input_tensor=None,
    input_shape=None,
    pooling=None,
    classes=1000,
    classifier_activation='softmax',
):
    """Instantiates the VGG19 architecture.

  Reference:
  - [Very Deep Convolutional Networks for Large-Scale Image Recognition](
      https://arxiv.org/abs/1409.1556) (ICLR 2015)

  By default, it loads weights pre-trained on ImageNet. Check 'weights' for
  other options.

  This model can be built both with 'channels_first' data format
  (channels, height, width) or 'channels_last' data format
  (height, width, channels).

  The default input size for this model is 224x224.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.vgg19.preprocess_input` for an example.

  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 32.
      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 block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=224,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

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

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

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

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

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

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

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            weights_path = data_utils.get_file(
                'vgg19_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='cbe5617147190e668d6c5d5026f83318')
        else:
            weights_path = data_utils.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)
    elif weights is not None:
        model.load_weights(weights)

    return model
In the functional API, models are created by specifying their inputs
and outputs in a graph of layers. That means that a single graph of layers
can be used to generate multiple models.

In the example below, we use the same stack of layers to instantiate two models:
an `encoder` model that turns image inputs into 16-dimensional vectors,
and an end-to-end `autoencoder` model for training.
"""

encoder_input = keras.Input(shape=(28, 28, 1), name='img')
x = layers.Conv2D(16, 3, activation='relu')(encoder_input)
x = layers.Conv2D(32, 3, activation='relu')(x)
x = layers.MaxPooling2D(3)(x)
x = layers.Conv2D(32, 3, activation='relu')(x)
x = layers.Conv2D(16, 3, activation='relu')(x)
encoder_output = layers.GlobalMaxPooling2D()(x)

encoder = keras.Model(encoder_input, encoder_output, name='encoder')
encoder.summary()

x = layers.Reshape((4, 4, 1))(encoder_output)
x = layers.Conv2DTranspose(16, 3, activation='relu')(x)
x = layers.Conv2DTranspose(32, 3, activation='relu')(x)
x = layers.UpSampling2D(3)(x)
x = layers.Conv2DTranspose(16, 3, activation='relu')(x)
decoder_output = layers.Conv2DTranspose(1, 3, activation='relu')(x)

autoencoder = keras.Model(encoder_input, decoder_output, name='autoencoder')
autoencoder.summary()
"""Note that we make the decoding architecture strictly symmetrical to the encoding architecture,
so that we get an output shape that is the same as the input shape `(28, 28, 1)`.
示例#14
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def DashNet(input_tensor=None,
            input_shape=None,
            pooling='avg',
            classes=2,
            classifier_activation='softmax'):
    if input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not backend.is_keras_tensor(input_tensor):
            img_input = layers.Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

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

    # customize model structure
    x = conv2d_bn(img_input, 32, 15, 3, strides=(3, 1), padding='valid')
    x = conv2d_bn(x, 32, 15, 3, padding='same')
    x = conv2d_bn(x, 64, 15, 3, padding='same')
    x = layers.MaxPooling2D(pool_size=(15, 3), strides=(5, 1))(x)

    x = conv2d_bn(x, 80, 1, 1, padding='same')
    x = conv2d_bn(x, 192, 15, 3, padding='same')
    x = layers.MaxPooling2D(pool_size=(15, 3), strides=(5, 2))(x)

    # mixed 0:
    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_avg_pool = layers.AveragePooling2D((3, 3),
                                              strides=(1, 1),
                                              padding='same')(x)
    branch_avg_pool = conv2d_bn(branch_avg_pool, 32, 1, 1)

    x = layers.concatenate(
        [branch1x1, branch5x5, branch3x3dbl, branch_avg_pool],
        axis=channel_axis,
        name='mixed0')

    if pooling == 'avg':
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    elif pooling == 'max':
        x = layers.GlobalMaxPooling2D(name='max_pool')(x)
    x = layers.Dense(classes,
                     activation=classifier_activation,
                     name='predictions')(x)

    if input_tensor is not None:
        inputs = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

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

    return model
示例#15
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def DenseNet(blocks,
             include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000,
             **kwargs):
    """Instantiates the DenseNet architecture.

    Optionally loads weights pre-trained on ImageNet.
    Note that the data format convention used by the model is
    the one specified in your Keras config at `~/.keras/keras.json`.

    # 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,
            and width and height should be no smaller than 32.
            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 block.
            - `avg` means that global average pooling
                will be applied to the output of the
                last convolutional block, 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=32,
                                      data_format=backend.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

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

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

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

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        x = layers.Dense(classes, activation='softmax', name='fc1000')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = keras_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

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

    # Load weights.
    if weights == 'imagenet':
        if include_top or (blocks != [6, 12, 24, 16]):
            raise ValueError('Only DenseNet121 without top is available'
                             ' pretrained')
        # NOTE: If your Hub Application has multiple configurations (e.g.,
        # DenseNet {121, 169, 201} x {include_top=True, include_top=False})
        # each of these would have their own weights_path/SavedModel.
        weights_path = 'densenet121_weights_tf_dim_ordering_tf_kernels_notop'
        # Download the SavedModel and use only the checkpoint (variables).
        path = resolve(('https://github.com/jharmsen/hub-application/'
                        'releases/download/v1/{}.tar.gz').format(weights_path))
        path = os.path.join(path, 'variables/variables')
        model.load_weights(path)
    elif weights is not None:
        model.load_weights(weights)

    return model
def ResNet(stack_fn,
           preact,
           use_bias,
           model_name='resnet',
           include_top=True,
           weights='imagenet',
           input_tensor=None,
           input_shape=None,
           pooling=None,
           classes=1000,
           layers_fn=None):
    """Instantiates the ResNet, ResNetV2, and ResNeXt architecture.

    Optionally loads weights pre-trained on ImageNet.
    Note that the data format convention used by the model is
    the one specified in your Keras config at `~/.keras/keras.json`.

    # Arguments
        stack_fn: a function that returns output tensor for the
            stacked residual blocks.
        preact: whether to use pre-activation or not
            (True for ResNetV2, False for ResNet and ResNeXt).
        use_bias: whether to use biases for convolutional layers or not
            (True for ResNet and ResNetV2, False for ResNeXt).
        model_name: string, model name.
        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 input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not backend.is_keras_tensor(input_tensor):
            img_input = layers.Input(tensor=input_tensor, shape=input_shape)
        else:
            img_input = input_tensor

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

    x = layers.ZeroPadding2D(padding=((3, 3), (3, 3)),
                             name='conv1_pad')(img_input)
    x = layers.Conv2D(64, 7, strides=2, use_bias=use_bias,
                      name='conv1_conv')(x)

    if preact is False:
        x = layers.BatchNormalization(axis=bn_axis,
                                      epsilon=1.001e-5,
                                      name='conv1_bn')(x)
        x = layers.Activation('relu', name='conv1_relu')(x)

    x = layers.ZeroPadding2D(padding=((1, 1), (1, 1)), name='pool1_pad')(x)
    x = layers.MaxPooling2D(3, strides=2, name='pool1_pool')(x)

    x = stack_fn(x)

    if preact is True:
        x = layers.BatchNormalization(axis=bn_axis,
                                      epsilon=1.001e-5,
                                      name='post_bn')(x)
        x = layers.Activation('relu', name='post_relu')(x)

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

    if layers_fn != None:
        x = layers_fn(x)

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

    # Create model.
    model = models.Model(inputs, x, name=model_name)

    # Load weights.
    if weights is not None:
        model.load_weights(weights)
    return model
示例#17
0
def ResNet(
    stack_fn,
    preact,
    model_name='resnet',
    head='one_head',
    head_mlp='',
    input_shape=None,
    pooling=None,
    activation='relu',
    bn_sync=BN_SYNC,
    num_class=1000,
    **kwargs):
    """Instantiates the ResNet, ResNetV2, and ResNeXt architecture.

    Reference paper:
    - [Deep Residual Learning for Image Recognition]
        (https://arxiv.org/abs/1512.03385) (CVPR 2015)

    Optionally loads weights pre-trained on ImageNet.
    Note that the data format convention used by the model is
    the one specified in your Keras config at `~/.keras/keras.json`.

    Caution: Be sure to properly pre-process your inputs to the application.
    Please see `applications.resnet.preprocess_input` for an example.

    Arguments:
        stack_fn: a function that returns output tensor for the
            stacked residual blocks.
        preact: whether to use pre-activation or not
            (True for ResNetV2, False for ResNet and ResNeXt).
        model_name: string, model name.
        head: whether to include the fully-connected
            layer at the top of the network.
        input_shape: optional shape tuple, only to be specified
            if `head` 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 `head` 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.
        num_class: optional number of classes to classify images
            into, only to be specified if `head` is True, and
            if no `weights` argument is specified.
        **kwargs: For backwards compatibility only.
    Returns:
        A `keras.Model` instance.

    Raises:
        ValueError: in case of invalid argument for `weights`,
            or invalid input shape.
    """

    # Input layer.
    inputs = img_input = layers.Input(shape=input_shape)

    # Conv1 block.
    # CIFAR (32x32) or STL-10 (96x96) use small input; otherwise use large input
    if input_shape[0] == 256:
        kernel_size, stride, maxpool = 7, 2, True
    elif input_shape[0] in [96, 128]:
        kernel_size, stride, maxpool = 5, 1, True
    elif input_shape[0] == 32:
        kernel_size, stride, maxpool = 3, 1, False
    else:
        raise NotImplementedError
    x = convnxn(img_input, filters=64, kernel_size=kernel_size,
        strides=stride, use_bias=preact,
        name='conv1_conv')
    if not preact:
        x = batchnorm(x, bn_sync=bn_sync, name='conv1_bn')
        x = nonlinearity(x, layer_activation=activation, name='conv1_'+activation)
    if maxpool:
        x = layers.MaxPooling2D(3, strides=2, padding='SAME',
            name='pool1_pool')(x)

    # Conv2 to Conv5 blocks
    x = stack_fn(x)
    if preact:
        x = batchnorm(x, bn_sync=bn_sync, name='post_bn')
        x = nonlinearity(x, layer_activation=activation, name='post_'+activation)

    # Pooling layer
    if pooling in ['avg', None]:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    elif pooling == 'max':
        x = layers.GlobalMaxPooling2D(name='max_pool')(x)

    # # Dropout layer
    # x = layers.Dropout(0.5)(x)
    # print("!! dropout layer")
        
    # Classifier and/or embedding head
    outputs = get_head(
        x, arch=head, dims=head_mlp, num_class=num_class,
        bn_sync=bn_sync,
        classifier_activation='linear')

    # Create model.
    if bn_sync:
        model_name += '_sbn'
    if not head in ['linear', None, False]:
        model_name += '_{}'.format(head)
        if head_mlp is not None and len(head_mlp) > 0:
            model_name += '_mlp' + '_'.join(['%d'%d for d in head_mlp])

    model = training.Model(inputs, outputs, name=model_name)
    res = model(tf.zeros((1, *input_shape)), training=False)
    model.dim_feat = tf.reshape(res['embeds'], (-1)).shape[0]
    
    return model
model = get_compiled_model()
model.fit(train_dataset, epochs=3)

"""### Passing data to multi-input, multi-output models

In the previous examples, we were considering a model with a single input (a tensor of shape `(764,)`) and a single output (a prediction tensor of shape `(10,)`). But what about models that have multiple inputs or outputs?

Consider the following model, which has an image input of shape `(32, 32, 3)` (that's `(height, width, channels)`) and a timeseries input of shape `(None, 10)` (that's `(timesteps, features)`). Our model will have two outputs computed from the combination of these inputs: a "score" (of shape `(1,)`) and a probability distribution over 5 classes (of shape `(10,)`).
"""

image_input = keras.Input(shape=(32, 32, 3), name='img_input')
timeseries_input = keras.Input(shape=(None, 10), name='ts_input')

x1 = layers.Conv2D(3, 3)(image_input)
x1 = layers.GlobalMaxPooling2D()(x1)

x2 = layers.Conv1D(3, 3)(timeseries_input)
x2 = layers.GlobalMaxPooling1D()(x2)

x = layers.concatenate([x1, x2])

score_output = layers.Dense(1, name='score_output')(x)
class_output = layers.Dense(5, activation='softmax', name='class_output')(x)

model = keras.Model(inputs=[image_input, timeseries_input],
                    outputs=[score_output, class_output])

"""Let's plot this model, so you can clearly see what we're doing here (note that the shapes shown in the plot are batch shapes, rather than per-sample shapes)."""

keras.utils.plot_model(model, 'multi_input_and_output_model.png', show_shapes=True)
示例#19
0
def MobileNetV2(input_shape=None,
                alpha=1.0,
                include_top=True,
                weights='imagenet',
                input_tensor=None,
                pooling=None,
                classes=1000,
                classifier_activation='softmax',
                **kwargs):
  """Instantiates the MobileNetV2 architecture.

  Reference paper:
  - [MobileNetV2: Inverted Residuals and Linear Bottlenecks]
  (https://arxiv.org/abs/1801.04381) (CVPR 2018)

  Optionally loads weights pre-trained on ImageNet.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.mobilenet_v2.preprocess_input` for an example.

  Arguments:
    input_shape: Optional shape tuple, to be specified if you would
      like to use a model with an input image resolution that is not
      (224, 224, 3).
      It should have exactly 3 inputs channels (224, 224, 3).
      You can also omit this option if you would like
      to infer input_shape from an input_tensor.
      If you choose to include both input_tensor and input_shape then
      input_shape will be used if they match, if the shapes
      do not match then we will throw an error.
      E.g. `(160, 160, 3)` would be one valid value.
    alpha: Float between 0 and 1. controls the width of the network.
      This is known as the width multiplier in the MobileNetV2 paper,
      but the name is kept for consistency with `applications.MobileNetV1`
      model in Keras.
      - 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.
    include_top: Boolean, whether to include the fully-connected
      layer at the top of the network. Defaults to `True`.
    weights: String, 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: String, 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 block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, and thus
          the output of the model will be a
          2D tensor.
      - `max` means that global max pooling will
          be applied.
    classes: Integer, optional number of classes to classify images
      into, only to be specified if `include_top` is True, and
      if no `weights` argument is specified.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.
    **kwargs: For backwards compatibility only.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape or invalid alpha, rows when
      weights='imagenet'
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
  if 'layers' in kwargs:
    global layers
    layers = kwargs.pop('layers')
  if kwargs:
    raise ValueError('Unknown argument(s): %s' % (kwargs,))
  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 both input_shape and input_tensor are used, they should match
  if input_shape is not None and input_tensor is not None:
    try:
      is_input_t_tensor = backend.is_keras_tensor(input_tensor)
    except ValueError:
      try:
        is_input_t_tensor = backend.is_keras_tensor(
            layer_utils.get_source_inputs(input_tensor))
      except ValueError:
        raise ValueError('input_tensor: ', input_tensor,
                         'is not type input_tensor')
    if is_input_t_tensor:
      if backend.image_data_format == 'channels_first':
        if backend.int_shape(input_tensor)[1] != input_shape[1]:
          raise ValueError('input_shape: ', input_shape, 'and input_tensor: ',
                           input_tensor,
                           'do not meet the same shape requirements')
      else:
        if backend.int_shape(input_tensor)[2] != input_shape[1]:
          raise ValueError('input_shape: ', input_shape, 'and input_tensor: ',
                           input_tensor,
                           'do not meet the same shape requirements')
    else:
      raise ValueError('input_tensor specified: ', input_tensor,
                       'is not a keras tensor')

  # If input_shape is None, infer shape from input_tensor
  if input_shape is None and input_tensor is not None:

    try:
      backend.is_keras_tensor(input_tensor)
    except ValueError:
      raise ValueError('input_tensor: ', input_tensor, 'is type: ',
                       type(input_tensor), 'which is not a valid type')

    if input_shape is None and not backend.is_keras_tensor(input_tensor):
      default_size = 224
    elif input_shape is None and backend.is_keras_tensor(input_tensor):
      if backend.image_data_format() == 'channels_first':
        rows = backend.int_shape(input_tensor)[2]
        cols = backend.int_shape(input_tensor)[3]
      else:
        rows = backend.int_shape(input_tensor)[1]
        cols = backend.int_shape(input_tensor)[2]

      if rows == cols and rows in [96, 128, 160, 192, 224]:
        default_size = rows
      else:
        default_size = 224

  # If input_shape is None and no input_tensor
  elif input_shape is None:
    default_size = 224

  # If input_shape is not None, assume default size
  else:
    if backend.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 [96, 128, 160, 192, 224]:
      default_size = rows
    else:
      default_size = 224

  input_shape = imagenet_utils.obtain_input_shape(
      input_shape,
      default_size=default_size,
      min_size=32,
      data_format=backend.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if backend.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 alpha not in [0.35, 0.50, 0.75, 1.0, 1.3, 1.4]:
      raise ValueError('If imagenet weights are being loaded, '
                       'alpha can be one of `0.35`, `0.50`, `0.75`, '
                       '`1.0`, `1.3` or `1.4` only.')

    if rows != cols or rows not in [96, 128, 160, 192, 224]:
      rows = 224
      logging.warning('`input_shape` is undefined or non-square, '
                      'or `rows` is not in [96, 128, 160, 192, 224].'
                      ' Weights for input shape (224, 224) will be'
                      ' loaded as the default.')

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

  channel_axis = 1 if backend.image_data_format() == 'channels_first' else -1

  first_block_filters = _make_divisible(32 * alpha, 8)
  x = layers.ZeroPadding2D(
      padding=imagenet_utils.correct_pad(img_input, 3),
      name='Conv1_pad')(img_input)
  x = layers.Conv2D(
      first_block_filters,
      kernel_size=3,
      strides=(2, 2),
      padding='valid',
      use_bias=False,
      name='Conv1')(
          x)
  x = layers.BatchNormalization(
      axis=channel_axis, epsilon=1e-3, momentum=0.999, name='bn_Conv1')(
          x)
  x = layers.ReLU(6., name='Conv1_relu')(x)

  x = _inverted_res_block(
      x, filters=16, alpha=alpha, stride=1, expansion=1, block_id=0)

  x = _inverted_res_block(
      x, filters=24, alpha=alpha, stride=2, expansion=6, block_id=1)
  x = _inverted_res_block(
      x, filters=24, alpha=alpha, stride=1, expansion=6, block_id=2)

  x = _inverted_res_block(
      x, filters=32, alpha=alpha, stride=2, expansion=6, block_id=3)
  x = _inverted_res_block(
      x, filters=32, alpha=alpha, stride=1, expansion=6, block_id=4)
  x = _inverted_res_block(
      x, filters=32, alpha=alpha, stride=1, expansion=6, block_id=5)

  x = _inverted_res_block(
      x, filters=64, alpha=alpha, stride=2, expansion=6, block_id=6)
  x = _inverted_res_block(
      x, filters=64, alpha=alpha, stride=1, expansion=6, block_id=7)
  x = _inverted_res_block(
      x, filters=64, alpha=alpha, stride=1, expansion=6, block_id=8)
  x = _inverted_res_block(
      x, filters=64, alpha=alpha, stride=1, expansion=6, block_id=9)

  x = _inverted_res_block(
      x, filters=96, alpha=alpha, stride=1, expansion=6, block_id=10)
  x = _inverted_res_block(
      x, filters=96, alpha=alpha, stride=1, expansion=6, block_id=11)
  x = _inverted_res_block(
      x, filters=96, alpha=alpha, stride=1, expansion=6, block_id=12)

  x = _inverted_res_block(
      x, filters=160, alpha=alpha, stride=2, expansion=6, block_id=13)
  x = _inverted_res_block(
      x, filters=160, alpha=alpha, stride=1, expansion=6, block_id=14)
  x = _inverted_res_block(
      x, filters=160, alpha=alpha, stride=1, expansion=6, block_id=15)

  x = _inverted_res_block(
      x, filters=320, alpha=alpha, stride=1, expansion=6, block_id=16)

  # no alpha applied to last conv as stated in the paper:
  # if the width multiplier is greater than 1 we
  # increase the number of output channels
  if alpha > 1.0:
    last_block_filters = _make_divisible(1280 * alpha, 8)
  else:
    last_block_filters = 1280

  x = layers.Conv2D(
      last_block_filters, kernel_size=1, use_bias=False, name='Conv_1')(
          x)
  x = layers.BatchNormalization(
      axis=channel_axis, epsilon=1e-3, momentum=0.999, name='Conv_1_bn')(
          x)
  x = layers.ReLU(6., name='out_relu')(x)

  if include_top:
    x = layers.GlobalAveragePooling2D()(x)
    imagenet_utils.validate_activation(classifier_activation, weights)
    x = layers.Dense(classes, activation=classifier_activation,
                     name='predictions')(x)

  else:
    if pooling == 'avg':
      x = layers.GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = layers.GlobalMaxPooling2D()(x)

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

  # Create model.
  model = training.Model(inputs, x, name='mobilenetv2_%0.2f_%s' % (alpha, rows))

  # Load weights.
  if weights == 'imagenet':
    if include_top:
      model_name = ('mobilenet_v2_weights_tf_dim_ordering_tf_kernels_' +
                    str(alpha) + '_' + str(rows) + '.h5')
      weight_path = BASE_WEIGHT_PATH + model_name
      weights_path = data_utils.get_file(
          model_name, weight_path, cache_subdir='models')
    else:
      model_name = ('mobilenet_v2_weights_tf_dim_ordering_tf_kernels_' +
                    str(alpha) + '_' + str(rows) + '_no_top' + '.h5')
      weight_path = BASE_WEIGHT_PATH + model_name
      weights_path = data_utils.get_file(
          model_name, weight_path, cache_subdir='models')
    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,
                      classifier_activation='softmax',
                      **kwargs):
  """Instantiates the Inception-ResNet v2 architecture.
  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.
  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.inception_resnet_v2.preprocess_input` for an example.
  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 75.
      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 block.
      - `'avg'` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.
    **kwargs: For backwards compatibility only.
  Returns:
    A `keras.Model` instance.
  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
  if 'layers' in kwargs:
    global layers
    layers = kwargs.pop('layers')
  if kwargs:
    raise ValueError('Unknown argument(s): %s' % (kwargs,))
  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 = imagenet_utils.obtain_input_shape(
      input_shape,
      default_size=299,
      min_size=75,
      data_format=backend.image_data_format(),
      require_flatten=include_top,
      weights=weights)

  if input_tensor is None:
    img_input = layers.Input(shape=input_shape)
  else:
    if not backend.is_keras_tensor(input_tensor):
      img_input = layers.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 = layers.MaxPooling2D(3, strides=2)(x)
  x = conv2d_bn(x, 80, 1, padding='valid')
  x = conv2d_bn(x, 192, 3, padding='valid')
  x = layers.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 = layers.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 backend.image_data_format() == 'channels_first' else 3
  x = layers.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 = layers.MaxPooling2D(3, strides=2, padding='valid')(x)
  branches = [branch_0, branch_1, branch_pool]
  x = layers.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 = layers.MaxPooling2D(3, strides=2, padding='valid')(x)
  branches = [branch_0, branch_1, branch_2, branch_pool]
  x = layers.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 = layers.GlobalAveragePooling2D(name='avg_pool')(x)
    imagenet_utils.validate_activation(classifier_activation, weights)
    x = layers.Dense(classes, activation=classifier_activation,
                     name='predictions')(x)
  else:
    if pooling == 'avg':
      x = layers.GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = layers.GlobalMaxPooling2D()(x)

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

  # Create model.
  model = training.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 = data_utils.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 = data_utils.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
示例#21
0
def DenseNet(
    blocks,
    include_top=True,
    weights='imagenet',
    input_tensor=None,
    input_shape=None,
    pooling=None,
    classes=1000,
    classifier_activation='softmax',
):
    """Instantiates the DenseNet architecture.

  Reference paper:
  - [Densely Connected Convolutional Networks]
    (https://arxiv.org/abs/1608.06993) (CVPR 2017 Best Paper Award)

  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.densenet.preprocess_input` for an example.

  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,
      and width and height should be no smaller than 32.
      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 block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=224,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

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

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

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)

        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

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

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            if blocks == [6, 12, 24, 16]:
                weights_path = data_utils.get_file(
                    'densenet121_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET121_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='9d60b8095a5708f2dcce2bca79d332c7')
            elif blocks == [6, 12, 32, 32]:
                weights_path = data_utils.get_file(
                    'densenet169_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET169_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='d699b8f76981ab1b30698df4c175e90b')
            elif blocks == [6, 12, 48, 32]:
                weights_path = data_utils.get_file(
                    'densenet201_weights_tf_dim_ordering_tf_kernels.h5',
                    DENSENET201_WEIGHT_PATH,
                    cache_subdir='models',
                    file_hash='1ceb130c1ea1b78c3bf6114dbdfd8807')
        else:
            if blocks == [6, 12, 24, 16]:
                weights_path = data_utils.get_file(
                    'densenet121_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET121_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='30ee3e1110167f948a6b9946edeeb738')
            elif blocks == [6, 12, 32, 32]:
                weights_path = data_utils.get_file(
                    'densenet169_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET169_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='b8c4d4c20dd625c148057b9ff1c1176b')
            elif blocks == [6, 12, 48, 32]:
                weights_path = data_utils.get_file(
                    'densenet201_weights_tf_dim_ordering_tf_kernels_notop.h5',
                    DENSENET201_WEIGHT_PATH_NO_TOP,
                    cache_subdir='models',
                    file_hash='c13680b51ded0fb44dff2d8f86ac8bb1')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
示例#22
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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,
              **kwargs):
    """Instantiates the MobileNet architecture.

  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. This is known as the width
      multiplier in the MobileNet paper. - 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. This is
      called the resolution multiplier in the MobileNet paper.
    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 block. - `avg` means that
      global average pooling will be applied to the output of the last
      convolutional block, 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.
    **kwargs: For backwards compatibility only.

  Returns:
    A Keras model instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
  """
    if 'layers' in kwargs:
        global layers
        layers = kwargs.pop('layers')
    if kwargs:
        raise ValueError('Unknown argument(s): %s' % (kwargs, ))
    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 backend.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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=default_size,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

    if backend.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]:
            rows = 224
            logging.warning('`input_shape` is undefined or non-square, '
                            'or `rows` is not in [128, 160, 192, 224]. '
                            'Weights for input shape (224, 224) will be'
                            ' loaded as the default.')

    if input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not backend.is_keras_tensor(input_tensor):
            img_input = layers.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 backend.image_data_format() == 'channels_first':
            shape = (int(1024 * alpha), 1, 1)
        else:
            shape = (1, 1, int(1024 * alpha))

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

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

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

    # Load weights.
    if weights == 'imagenet':
        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)
            weight_path = BASE_WEIGHT_PATH + model_name
            weights_path = data_utils.get_file(model_name,
                                               weight_path,
                                               cache_subdir='models')
        else:
            model_name = 'mobilenet_%s_%d_tf_no_top.h5' % (alpha_text, rows)
            weight_path = BASE_WEIGHT_PATH + model_name
            weights_path = data_utils.get_file(model_name,
                                               weight_path,
                                               cache_subdir='models')
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
def ResNet50Plus(include_top=False,
                 input_tensor=None,
                 input_shape=(192, 192, 3),
                 alpha=1.0,
                 pooling='cov',
                 classes=8,
                 **kwargs):
    """ Adaption of ResNet50 that uses ELU instead of ReLU and uses less batch normalization layers. """

    if input_tensor is None:
        img_input = layers.Input(shape=input_shape)
    else:
        if not K.is_keras_tensor(input_tensor):
            img_input = layers.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 = layers.ZeroPadding2D(padding=(3, 3), name='conv1_pad')(img_input)
    x = layers.Conv2D(64, (7, 7),
                      strides=(2, 2),
                      padding='valid',
                      kernel_initializer='he_normal',
                      name='conv1')(x)
    x = layers.BatchNormalization(axis=bn_axis, name='bn_conv1')(x)
    x = layers.ELU(alpha=alpha)(x)
    x = layers.ZeroPadding2D(padding=(1, 1), name='pool1_pad')(x)
    x = layers.MaxPooling2D((3, 3), strides=(2, 2))(x)

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

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

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

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

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        x = layers.Dense(classes, activation='softmax', name='fc1000')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)
        elif pooling == 'cov':
            # Reduce number of channels before applying covariance pooling
            # num_channels = int(np.ceil(np.max(np.roots([1, 1, -2*classes]))))
            x = layers.Conv2D(classes, (1, 1),
                              padding='valid',
                              kernel_initializer='he_normal',
                              name='reduce_channels')(x)
            x = GlobalCovPooling2D(num_iter=5)(x)
            x = layers.Dense(classes,
                             activation='softmax',
                             name='fc{}'.format(classes))(x)
        else:
            warnings.warn('The output shape of `ResNet50(include_top=False)` '
                          'has been changed since Keras 2.2.0.')

    # 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='resnet50plus')

    return model
示例#24
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def SmallResNet(stack_fn,
                preact,
                use_bias,
                model_name='resnet',
                include_top=True,
                input_tensor=None,
                input_shape=None,
                pooling=None,
                classes=1000,
                classifier_activation='softmax',
                **kwargs):
    # Determine proper input shape
    input_shape = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=224,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top)

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

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

    x = layers.Conv2D(64,
                      3,
                      padding='same',
                      use_bias=use_bias,
                      name='conv1_conv')(img_input)

    if not preact:
        x = layers.BatchNormalization(axis=bn_axis,
                                      epsilon=1.001e-5,
                                      name='conv1_bn')(x)
        x = layers.Activation('relu', name='conv1_relu')(x)

    x = stack_fn(x)

    if preact:
        x = layers.BatchNormalization(axis=bn_axis,
                                      epsilon=1.001e-5,
                                      name='post_bn')(x)
        x = layers.Activation('relu', name='post_relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    model = training.Model(inputs, x, name=model_name)

    return model
示例#25
0
def InceptionV3(
    include_top=True,
    weights='imagenet',
    input_tensor=None,
    input_shape=None,
    pooling=None,
    classes=1000,
    classifier_activation='softmax',
):
    """Instantiates the Inception v3 architecture.

  Reference paper:
  - [Rethinking the Inception Architecture for Computer Vision](
      http://arxiv.org/abs/1512.00567) (CVPR 2016)

  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in the `tf.keras.backend.image_data_format()`.

  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.inception_v3.preprocess_input` for an example.

  Arguments:
    include_top: Boolean, whether to include the fully-connected
      layer at the top, as the last layer of the network. Default to `True`.
    weights: One of `None` (random initialization),
      `imagenet` (pre-training on ImageNet),
      or the path to the weights file to be loaded. Default to `imagenet`.
    input_tensor: Optional Keras tensor (i.e. output of `layers.Input()`)
      to use as image input for the model. `input_tensor` is useful for sharing
      inputs between multiple different networks. Default to None.
    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 75.
      E.g. `(150, 150, 3)` would be one valid value.
      `input_shape` will be ignored if the `input_tensor` is provided.
    pooling: Optional pooling mode for feature extraction
      when `include_top` is `False`.
      - `None` (default) means that the output of the model will be
          the 4D tensor output of the last convolutional block.
      - `avg` means that global average pooling
          will be applied to the output of the
          last convolutional block, 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 to 1000.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.

  Returns:
    A `keras.Model` instance.

  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=299,
        min_size=75,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

    if backend.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 = layers.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 = layers.MaxPooling2D((3, 3), strides=(2, 2))(x)

    # mixed 0: 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 = layers.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 288
    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 = layers.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 288
    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 = layers.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 = layers.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 = layers.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 = layers.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 = layers.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 = layers.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 = layers.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 = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

    # Load weights.
    if weights == 'imagenet':
        if include_top:
            weights_path = data_utils.get_file(
                'inception_v3_weights_tf_dim_ordering_tf_kernels.h5',
                WEIGHTS_PATH,
                cache_subdir='models',
                file_hash='9a0d58056eeedaa3f26cb7ebd46da564')
        else:
            weights_path = data_utils.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
示例#26
0
def MobileNetV2(input_shape=None,
                alpha=1.0,
                include_top=True,
                weights='imagenet',
                input_tensor=None,
                pooling=None,
                classes=1000,
                **kwargs):
    """Instantiates the MobileNetV2 architecture.
    # Arguments
        input_shape: optional shape tuple, to be specified if you would
            like to use a model with an input img resolution that is not
            (224, 224, 3).
            It should have exactly 3 inputs channels (224, 224, 3).
            You can also omit this option if you would like
            to infer input_shape from an input_tensor.
            If you choose to include both input_tensor and input_shape then
            input_shape will be used if they match, if the shapes
            do not match then we will throw an error.
            E.g. `(160, 160, 3)` would be one valid value.
        alpha: controls the width of the network. This is known as the
        width multiplier in the MobileNetV2 paper, but the name is kept for
        consistency with MobileNetV1 in Keras.
            - 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.
        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 block.
            - `avg` means that global average pooling
                will be applied to the output of the
                last convolutional block, 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 or invalid alpha, rows when
            weights='imagenet'
    """

    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 both input_shape and input_tensor are used, they should match
    if input_shape is not None and input_tensor is not None:
        try:
            is_input_t_tensor = backend.is_keras_tensor(input_tensor)
        except ValueError:
            try:
                is_input_t_tensor = backend.is_keras_tensor(
                    keras_utils.get_source_inputs(input_tensor))
            except ValueError:
                raise ValueError('input_tensor: ', input_tensor,
                                 'is not type input_tensor')
        if is_input_t_tensor:
            if backend.image_data_format == 'channels_first':
                if backend.int_shape(input_tensor)[1] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
            else:
                if backend.int_shape(input_tensor)[2] != input_shape[1]:
                    raise ValueError(
                        'input_shape: ', input_shape, 'and input_tensor: ',
                        input_tensor,
                        'do not meet the same shape requirements')
        else:
            raise ValueError('input_tensor specified: ', input_tensor,
                             'is not a keras tensor')

    # If input_shape is None, infer shape from input_tensor
    if input_shape is None and input_tensor is not None:

        try:
            backend.is_keras_tensor(input_tensor)
        except ValueError:
            raise ValueError('input_tensor: ', input_tensor, 'is type: ',
                             type(input_tensor), 'which is not a valid type')

        if input_shape is None and not backend.is_keras_tensor(input_tensor):
            default_size = 224
        elif input_shape is None and backend.is_keras_tensor(input_tensor):
            if backend.image_data_format() == 'channels_first':
                rows = backend.int_shape(input_tensor)[2]
                cols = backend.int_shape(input_tensor)[3]
            else:
                rows = backend.int_shape(input_tensor)[1]
                cols = backend.int_shape(input_tensor)[2]

            if rows == cols and rows in [96, 128, 160, 192, 224]:
                default_size = rows
            else:
                default_size = 224

    # If input_shape is None and no input_tensor
    elif input_shape is None:
        default_size = 224

    # If input_shape is not None, assume default size
    else:
        if backend.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 [96, 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=backend.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    if backend.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 alpha not in [0.35, 0.50, 0.75, 1.0, 1.3, 1.4]:
            raise ValueError('If imagenet weights are being loaded, '
                             'alpha can be one of `0.35`, `0.50`, `0.75`, '
                             '`1.0`, `1.3` or `1.4` only.')

        if rows != cols or rows not in [96, 128, 160, 192, 224]:
            rows = 224
            warnings.warn('MobileNet shape is undefined.'
                          ' Weights for input shape'
                          '(224, 224) will be loaded.')

    if backend.image_data_format() != 'channels_last':
        warnings.warn('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.')
        backend.set_image_data_format('channels_last')
        old_data_format = 'channels_first'
    else:
        old_data_format = None

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

    first_block_filters = _make_divisible(32 * alpha, 8)
    x = layers.ZeroPadding2D(padding=correct_pad(backend, img_input, 3),
                             name='Conv1_pad')(img_input)
    x = layers.Conv2D(first_block_filters,
                      kernel_size=3,
                      strides=(2, 2),
                      padding='valid',
                      use_bias=False,
                      name='Conv1')(x)
    x = layers.BatchNormalization(epsilon=1e-3,
                                  momentum=0.999,
                                  name='bn_Conv1')(x)
    x = layers.ReLU(6., name='Conv1_relu')(x)

    x = _inverted_res_block(x,
                            filters=16,
                            alpha=alpha,
                            stride=1,
                            expansion=1,
                            block_id=0)

    x = _inverted_res_block(x,
                            filters=24,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=1)
    x = _inverted_res_block(x,
                            filters=24,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=2)

    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=3)
    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=4)
    x = _inverted_res_block(x,
                            filters=32,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=5)

    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=6)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=7)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=8)
    x = _inverted_res_block(x,
                            filters=64,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=9)

    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=10)
    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=11)
    x = _inverted_res_block(x,
                            filters=96,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=12)

    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=2,
                            expansion=6,
                            block_id=13)
    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=14)
    x = _inverted_res_block(x,
                            filters=160,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=15)

    x = _inverted_res_block(x,
                            filters=320,
                            alpha=alpha,
                            stride=1,
                            expansion=6,
                            block_id=16)

    # no alpha applied to last conv as stated in the paper:
    # if the width multiplier is greater than 1 we
    # increase the number of output channels
    if alpha > 1.0:
        last_block_filters = _make_divisible(1280 * alpha, 8)
    else:
        last_block_filters = 1280

    x = layers.Conv2D(last_block_filters,
                      kernel_size=1,
                      use_bias=False,
                      name='Conv_1')(x)
    x = layers.BatchNormalization(epsilon=1e-3,
                                  momentum=0.999,
                                  name='Conv_1_bn')(x)
    x = layers.ReLU(6., name='out_relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D()(x)
        x = layers.Dense(classes,
                         activation='softmax',
                         use_bias=True,
                         name='Logits')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D()(x)
        elif pooling == 'max':
            x = layers.GlobalMaxPooling2D()(x)

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

    # Create model.
    model = models.Model(inputs,
                         x,
                         name='mobilenetv2_%0.2f_%s' % (alpha, rows))

    # Load weights.
    if weights == 'imagenet':
        if backend.image_data_format() == 'channels_first':
            raise ValueError('Weights for "channels_first" format '
                             'are not available.')

        if include_top:
            model_name = ('mobilenet_v2_weights_tf_dim_ordering_tf_kernels_' +
                          str(alpha) + '_' + str(rows) + '.h5')
            weigh_path = BASE_WEIGHT_PATH + model_name
            weights_path = keras_utils.get_file(model_name,
                                                weigh_path,
                                                cache_subdir='models')
        else:
            model_name = ('mobilenet_v2_weights_tf_dim_ordering_tf_kernels_' +
                          str(alpha) + '_' + str(rows) + '_no_top' + '.h5')
            weigh_path = BASE_WEIGHT_PATH + model_name
            weights_path = keras_utils.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:
        backend.set_image_data_format(old_data_format)
    return model
示例#27
0
def AlexNet(include_top=True,
            input_tensor=None,
            input_shape=None,
            pooling=None,
            classes=1000):
  """ Instantiates the AlexNet architecture.

  Args:
    include_top: whether to include the 3 fully-connected
            layers at the top of the network.
    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 input channels,
            and width and height should be no smaller than 32.
            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 block.
            - `avg` means that global average pooling
                will be applied to the output of the
                last convolutional block, 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.

  """
  if classes == 1000:
    raise ValueError('If use dataset is `imagenet`, please use it,'
                     'otherwise please use classifier images classes.')

  if input_tensor is None:
    img_input = layers.Input(shape=input_shape)
  else:
    if not backend.is_keras_tensor(input_tensor):
      img_input = layers.Input(tensor=input_tensor, shape=input_shape)
    else:
      img_input = input_tensor
  x = layers.Conv2D(96, (11, 11),
                    strides=4,
                    activation=tf.nn.relu,
                    padding='same',
                    name='conv1')(img_input)
  x = layers.MaxPool2D((2, 2), strides=(2, 2), name='max_pool1')(x)

  x = layers.Conv2D(256, (5, 5),
                    strides=1,
                    activation=tf.nn.relu,
                    padding='same',
                    name='conv2')(x)
  x = layers.MaxPool2D((3, 3), strides=(2, 2), name='max_pool2')(x)

  x = layers.Conv2D(384, (3, 3),
                    strides=1,
                    activation=tf.nn.relu,
                    padding='same',
                    name='conv3')(x)
  x = layers.Conv2D(384, (3, 3),
                    strides=1,
                    activation=tf.nn.relu,
                    padding='same',
                    name='conv4')(x)
  x = layers.Conv2D(256, (3, 3),
                    strides=1,
                    activation=tf.nn.relu,
                    padding='same',
                    )(x)
  x = layers.MaxPool2D((3, 3), strides=(2, 2), name='max_pool3')(x)

  x = layers.AvgPool2D((6, 6), strides=(6, 6), name='avg_pool1')(x)

  if include_top:
    # Classification block
    x = layers.Flatten(name='flatten')(x)
    x = layers.Dropout(0.3, name='drop1')(x)
    x = layers.Dense(4096, activation=tf.nn.relu, name='fc1')(x)
    x = layers.Dropout(0.3, name='drop2')(x)
    x = layers.Dense(4096, activation=tf.nn.relu, name='fc2')(x)
    x = layers.Dense(classes, activation=tf.nn.softmax, name='predictions')(x)
  else:
    if pooling == 'avg':
      x = layers.GlobalAveragePooling2D()(x)
    elif pooling == 'max':
      x = layers.GlobalMaxPooling2D()(x)

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

  model = models.Model(inputs, x, name='AlexNet')
  return model
def EfficientNet(input_shape, block_args_list, global_params, include_top=True, pooling=None):
    batch_norm_momentum = global_params.batch_norm_momentum
    batch_norm_epsilon = global_params.batch_norm_epsilon
    if global_params.data_format == 'channels_first':
        channel_axis = 1
    else:
        channel_axis = -1

    # Stem part
    inputs = KL.Input(shape=input_shape)
    x = inputs
    x = KL.Conv2D(
        filters=round_filters(32, global_params),
        kernel_size=[3, 3],
        strides=[2, 2],
        kernel_initializer=ConvKernalInitializer(),
        padding='same',
        use_bias=False
    )(x)
    x = KL.BatchNormalization(
        axis=channel_axis,
        momentum=batch_norm_momentum,
        epsilon=batch_norm_epsilon
    )(x)
    x = Swish()(x)

    # Blocks part
    block_idx = 1
    n_blocks = sum([block_args.num_repeat for block_args in block_args_list])
    drop_rate = global_params.drop_connect_rate or 0
    drop_rate_dx = drop_rate / n_blocks

    for block_args in block_args_list:
        assert block_args.num_repeat > 0
        # Update block input and output filters based on depth multiplier.
        block_args = block_args._replace(
            input_filters=round_filters(block_args.input_filters, global_params),
            output_filters=round_filters(block_args.output_filters, global_params),
            num_repeat=round_repeats(block_args.num_repeat, global_params)
        )

        # The first block needs to take care of stride and filter size increase.
        x = MBConvBlock(block_args, global_params,
                        drop_connect_rate=drop_rate_dx * block_idx)(x)
        block_idx += 1

        if block_args.num_repeat > 1:
            block_args = block_args._replace(input_filters=block_args.output_filters, strides=[1, 1])

        for _ in xrange(block_args.num_repeat - 1):
            x = MBConvBlock(block_args, global_params,
                            drop_connect_rate=drop_rate_dx * block_idx)(x)
            block_idx += 1

    # Head part
    x = KL.Conv2D(
        filters=round_filters(1280, global_params),
        kernel_size=[1, 1],
        strides=[1, 1],
        kernel_initializer=ConvKernalInitializer(),
        padding='same',
        use_bias=False
    )(x)
    x = KL.BatchNormalization(
        axis=channel_axis,
        momentum=batch_norm_momentum,
        epsilon=batch_norm_epsilon
    )(x)
    x = Swish()(x)

    if include_top:
        x = KL.GlobalAveragePooling2D(data_format=global_params.data_format)(x)
        if global_params.dropout_rate > 0:
            x = KL.Dropout(global_params.dropout_rate)(x)
        x = KL.Dense(global_params.num_classes, kernel_initializer=DenseKernalInitializer())(x)
        x = KL.Activation('softmax')(x)
    else:
        if pooling == 'avg':
            x = KL.GlobalAveragePooling2D(data_format=global_params.data_format)(x)
        elif pooling == 'max':
            x = KL.GlobalMaxPooling2D(data_format=global_params.data_format)(x)

    outputs = x
    model = KM.Model(inputs, outputs)

    return model
示例#29
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def ResNet(stack_fn,
           preact,
           use_bias,
           model_name='resnet',
           include_top=True,
           weights='imagenet',
           input_tensor=None,
           input_shape=None,
           pooling=None,
           classes=1000,
           classifier_activation='softmax',
           **kwargs):
    """Instantiates the ResNet, ResNetV2, and ResNeXt architecture.
  Optionally loads weights pre-trained on ImageNet.
  Note that the data format convention used by the model is
  the one specified in your Keras config at `~/.keras/keras.json`.
  Caution: Be sure to properly pre-process your inputs to the application.
  Please see `applications.resnet.preprocess_input` for an example.
  Arguments:
    stack_fn: a function that returns output tensor for the
      stacked residual blocks.
    preact: whether to use pre-activation or not
      (True for ResNetV2, False for ResNet and ResNeXt).
    use_bias: whether to use biases for convolutional layers or not
      (True for ResNet and ResNetV2, False for ResNeXt).
    model_name: string, model name.
    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.
    classifier_activation: A `str` or callable. The activation function to use
      on the "top" layer. Ignored unless `include_top=True`. Set
      `classifier_activation=None` to return the logits of the "top" layer.
    **kwargs: For backwards compatibility only.
  Returns:
    A `keras.Model` instance.
  Raises:
    ValueError: in case of invalid argument for `weights`,
      or invalid input shape.
    ValueError: if `classifier_activation` is not `softmax` or `None` when
      using a pretrained top layer.
  """
    if 'layers' in kwargs:
        global layers
        layers = kwargs.pop('layers')
    if kwargs:
        raise ValueError('Unknown argument(s): %s' % (kwargs, ))
    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 = imagenet_utils.obtain_input_shape(
        input_shape,
        default_size=224,
        min_size=32,
        data_format=backend.image_data_format(),
        require_flatten=include_top,
        weights=weights)

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

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

    x = layers.ZeroPadding2D(padding=((3, 3), (3, 3)),
                             name='conv1_pad')(img_input)
    x = layers.Conv2D(64, 7, strides=2, use_bias=use_bias,
                      name='conv1_conv')(x)

    if not preact:
        x = tf.keras.layers.experimental.SyncBatchNormalization(
            axis=bn_axis, name='conv1_bn')(x)
        x = layers.Activation('relu', name='conv1_relu')(x)

    x = layers.ZeroPadding2D(padding=((1, 1), (1, 1)), name='pool1_pad')(x)
    x = layers.MaxPooling2D(3, strides=2, name='pool1_pool')(x)

    x = stack_fn(x)

    if preact:
        x = tf.keras.layers.experimental.SyncBatchNormalization(
            axis=bn_axis, name='post_bn')(x)
        x = layers.Activation('relu', name='post_relu')(x)

    if include_top:
        x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        imagenet_utils.validate_activation(classifier_activation, weights)
        x = layers.Dense(classes,
                         activation=classifier_activation,
                         name='predictions')(x)
    else:
        if pooling == 'avg':
            x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
        elif pooling == 'max':
            x = layers.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 = layer_utils.get_source_inputs(input_tensor)
    else:
        inputs = img_input

    # Create model.
    model = training.Model(inputs, x, name=model_name)

    # Load weights.
    if (weights == 'imagenet') and (model_name in WEIGHTS_HASHES):
        if include_top:
            file_name = model_name + '_weights_tf_dim_ordering_tf_kernels.h5'
            file_hash = WEIGHTS_HASHES[model_name][0]
        else:
            file_name = model_name + '_weights_tf_dim_ordering_tf_kernels_notop.h5'
            file_hash = WEIGHTS_HASHES[model_name][1]
        weights_path = data_utils.get_file(file_name,
                                           BASE_WEIGHTS_PATH + file_name,
                                           cache_subdir='models',
                                           file_hash=file_hash)
        model.load_weights(weights_path)
    elif weights is not None:
        model.load_weights(weights)

    return model
示例#30
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def ResNet50(include_top=True,
             weights='imagenet',
             input_tensor=None,
             input_shape=None,
             pooling=None,
             classes=1000,
             **kwargs):
    """Instantiates the ResNet50 architecture.
    Optionally loads weights pre-trained on ImageNet.
    Note that the data format convention used by the model is
    the one specified in your Keras config at `~/.keras/keras.json`.
    # 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 32.
            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 block.
            - `avg` means that global average pooling
                will be applied to the output of the
                last convolutional block, 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.
    """
    # global backend, layers, models, keras_utils
    # backend, layers, models, keras_utils = get_submodules_from_kwargs(kwargs)

    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=32,
                                      data_format=backend.image_data_format(),
                                      require_flatten=include_top,
                                      weights=weights)

    with tf.name_scope("input_layer") as scope:
        if input_tensor is None:
            img_input = layers.Input(shape=input_shape)
        else:
            if not backend.is_keras_tensor(input_tensor):
                img_input = layers.Input(tensor=input_tensor,
                                         shape=input_shape)
            else:
                img_input = input_tensor
        if backend.image_data_format() == 'channels_last':
            bn_axis = 3
        else:
            bn_axis = 1

    with tf.name_scope("resnet") as scope:
        x = layers.ZeroPadding2D(padding=(3, 3), name='conv1_pad')(img_input)
        x = layers.Conv2D(64, (7, 7),
                          strides=(2, 2),
                          padding='valid',
                          kernel_initializer='he_normal',
                          name='conv1')(x)
        x = layers.BatchNormalization(axis=bn_axis, name='bn_conv1')(x)
        x = layers.Activation('relu')(x)
        x = layers.ZeroPadding2D(padding=(1, 1), name='pool1_pad')(x)
        x = layers.MaxPooling2D((3, 3), strides=(2, 2))(x)

        with tf.name_scope("module_0") as scope:
            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')

        with tf.name_scope("module_1") as scope:
            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')

        with tf.name_scope("module_2") as scope:
            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')

        with tf.name_scope("module_3") as scope:
            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')

        with tf.name_scope("top_layer") as scope:
            if include_top:
                x = layers.GlobalAveragePooling2D(name='avg_pool')(x)
                x = layers.Dense(classes, activation='softmax',
                                 name='fc1000')(x)
            else:
                if pooling == 'avg':
                    x = layers.GlobalAveragePooling2D()(x)
                elif pooling == 'max':
                    x = layers.GlobalMaxPooling2D()(x)
                else:
                    warnings.warn(
                        'The output shape of `ResNet50(include_top=False)` '
                        'has been changed since Keras 2.2.0.')

        with tf.name_scope("input_layer") as scope:
            # Ensure that the model takes into account
            # any potential predecessors of `input_tensor`.
            if input_tensor is not None:
                inputs = keras_utils.get_source_inputs(input_tensor)
            else:
                inputs = img_input

    # Create model.
    model = models.Model(inputs, x, name='resnet50')

    # Load weights.
    # if weights == 'imagenet':
    #     if include_top:
    #         weights_path = keras_utils.get_file(
    #             'resnet50_weights_tf_dim_ordering_tf_kernels.h5',
    #             WEIGHTS_PATH,
    #             cache_subdir='models',
    #             md5_hash='a7b3fe01876f51b976af0dea6bc144eb')
    #     else:
    #         weights_path = keras_utils.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 backend.backend() == 'theano':
    #         keras_utils.convert_all_kernels_in_model(model)
    # elif weights is not None:
    #     model.load_weights(weights)

    return model