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"""VGG19 model for Keras.
# Reference
- [Very Deep Convolutional Networks for Large-Scale Image Recognition]( https://arxiv.org/abs/1409.1556) (ICLR 2015)
""" from __future__ import absolute_import from __future__ import division from __future__ import print_function
import os
from . import get_submodules_from_kwargs from . import imagenet_utils from .imagenet_utils import decode_predictions from .imagenet_utils import _obtain_input_shape
preprocess_input = imagenet_utils.preprocess_input
WEIGHTS_PATH = ('https://github.com/fchollet/deep-learning-models/' 'releases/download/v0.1/' 'vgg19_weights_tf_dim_ordering_tf_kernels.h5') WEIGHTS_PATH_NO_TOP = ('https://github.com/fchollet/deep-learning-models/' 'releases/download/v0.1/' 'vgg19_weights_tf_dim_ordering_tf_kernels_notop.h5')
def VGG19(include_top=True, weights='imagenet', input_tensor=None, input_shape=None, pooling=None, classes=1000, **kwargs): """Instantiates the VGG19 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 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.
# Returns A Keras model instance.
# Raises ValueError: in case of invalid argument for `weights`, or invalid input shape. """ 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)
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) 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 = keras_utils.get_source_inputs(input_tensor) else: inputs = img_input # Create model. model = models.Model(inputs, x, name='vgg19')
# Load weights. if weights == 'imagenet': if include_top: weights_path = keras_utils.get_file( 'vgg19_weights_tf_dim_ordering_tf_kernels.h5', WEIGHTS_PATH, cache_subdir='models', file_hash='cbe5617147190e668d6c5d5026f83318') else: weights_path = keras_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) if backend.backend() == 'theano': keras_utils.convert_all_kernels_in_model(model) elif weights is not None: model.load_weights(weights)
return model
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