예제 #1
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                  metrics=['acc'])
    return model


if __name__ == '__main__':
    original_dataset_dir = r'D:\tmp\datesets\python_ml_data\data\kaggle_original_data'
    base_dir = r'D:\tmp\cats_and_dogs_small'
    train_dir = os.path.join(base_dir, 'train')
    validation_dir = os.path.join(base_dir, 'validation')
    test_dir = os.path.join(base_dir, 'test')
    datagen = ImageDataGenerator(rescale=1. / 255)
    batch_size = 20

    # include_top 指定模型最后是否包含密集连接分类器。默认情况下,这个密集连接分类器对应于ImageNet 的1000 个类别
    conv_base = VGG16(weights='imagenet',
                      include_top=False,
                      input_shape=(150, 150, 3))
    conv_base.summary()

    # 这里输出的train future是已经通过VGG16计算输出的结果,所以后面build model没有传入VGG16模型
    # 这种模型训练快,但是不能使用数据增强,因为VGG16部分模型是冻结的
    train_features, train_labels = extract_features(train_dir, 2000)
    validation_features, validation_labels = extract_features(validation_dir, 1000)
    test_features, test_labels = extract_features(test_dir, 1000)
    train_features = np.reshape(train_features, (2000, 4 * 4 * 512))
    validation_features = np.reshape(validation_features, (1000, 4 * 4 * 512))
    test_features = np.reshape(test_features, (1000, 4 * 4 * 512))

    model = build_model()
    history = model.fit(train_features, train_labels, epochs=30, batch_size=20,
                        validation_data=(validation_features, validation_labels))
# img_ = ExtractTestInput(Image_test)
img_ = X_[index_to_predict]
plt.title("Low Light Image", fontsize=20)
plt.imshow(img_)

plt.subplot(5, 5, 1 + 2)
img_[:, :, :] = Prediction[:, :, :]
plt.title("Enhanced Image", fontsize=20)
plt.imshow(img_)

# ## Experiments

# In[ ]:

base_model = VGG16(weights="imagenet",
                   include_top=False,
                   input_tensor=Input(shape=(128, 128, 3)))

# In[ ]:

headmodel = base_model.layers[2].output

# In[ ]:

headmodel = Conv2D(3, (3, 3), strides=1, padding="same",
                   activation="relu")(headmodel)

# In[ ]:

# Output_ = InstantiateModel(Input_Sample)
model = Model(inputs=base_model.input, outputs=headmodel)
# %%
from tensorflow.keras.applications import VGG16

conv_base = VGG16(include_top=False, input_shape=(150, 150, 3))
conv_base.summary()

# %%
import os
import numpy as np
from tensorflow.keras.preprocessing.image import ImageDataGenerator

base_dir = 'cats_and_dogs_small'
train_dir = os.path.join(base_dir, 'train')
validation_dir = os.path.join(base_dir, 'validation')
test_dir = os.path.join(base_dir, 'test')

datagen = ImageDataGenerator(rescale=1. / 255)
batch_size = 20


def extract_features(directory, sample_count):
    features = np.zeros(shape=(sample_count, 4, 4, 512))
    labels = np.zeros(shape=(sample_count))
    generator = datagen.flow_from_directory(directory,
                                            target_size=(150, 150),
                                            batch_size=batch_size,
                                            class_mode='binary')
    i = 0
    for inputs_batch, labels_batch in generator:
        features_batch = conv_base.predict(inputs_batch)
        features[i * batch_size:(i + 1) * batch_size] = features_batch
예제 #4
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from tensorflow.keras.applications import VGG16
from tensorflow.keras.layers import Dense, Flatten
from tensorflow.keras.models import Sequential

vgg16 = VGG16(weights='imagenet', include_top=False, input_shape=(32, 32, 3))

print(vgg16.weights)


vgg16.trainable = False
vgg16.summary()
print(len(vgg16.weights)) # 26
print(len(vgg16.trainable_weights)) # 0

model = Sequential()
model.add(vgg16)
model.add(Flatten())
model.add(Dense(10))
model.add(Dense(5))
model.add(Dense(1))#, activation='softmax'))

model.summary()

print("가중치의 수 : ", len(model.weights)) # 26 -> 32
print("동결된 후 훈련되는 가중치의 수 : ", len(model.trainable_weights)) # 0 -> 6

import pandas as pd

pd.set_option('max_colwidth',-1)
layers = [(layer,layer.name, layer.trainable) for layer in model.layers] 
aaa = pd.DataFrame(layers, columns= ['Layer Type', 'Layer name', 'Layer Trainable'])
예제 #5
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from tensorflow.keras.applications import VGG16

model = VGG16(weights='imagenet', include_top=True, input_shape=(224, 224, 3))
# model = VGG16()

model.trainable = False
model.summary()
print(len(model.weights))
print(len(model.trainable_weights))

# include_top= False
# Total params: 14,714,688
# Trainable params: 0
# Non-trainable params: 14,714,688
# _________________________________________________________________
# 26
# 0

# include_top= True
# Total params: 138,357,544
# Trainable params: 0
# Non-trainable params: 138,357,544
# _________________________________________________________________
# 32
# 0
예제 #6
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import os
import pandas as pd
import numpy as np
import imageio
from tensorflow import keras
from tensorflow.keras.applications import VGG16
from tensorflow.keras.applications.vgg16 import preprocess_input
from tensorflow.keras.models import Model

img_input = keras.Input(shape=(400, 400, 3))

base_model = VGG16(weights="imagenet",
                   include_top=False,
                   input_tensor=img_input,
                   pooling="max")
#model = Model(inputs=base_model.input, outputs=base_model.get_layer('back').output)
all_images = []
img_folders = os.listdir('./google_image/')
img_folders.remove(".DS_Store")
for i in img_folders:
    folder_images = [
        "./google_image/" + i + "/" + j
        for j in os.listdir("./google_image/" + i)
    ]
    all_images = all_images + folder_images

#test_x = preprocess_input(np.expand_dims(np.array(imageio.imread(all_images[0],pilmode="RGB")),axis=0))
#test = base_model.predict(test_x)
#print(test.shape)

features = []
예제 #7
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						X_train.shape[0], 
						X_train.shape[1],
						X_train.shape[2])

X_test = X_test.reshape(-1, 
						X_test.shape[0], 
						X_test.shape[1],
						X_test.shape[2])
'''

# data augmentation
trainAug = ImageDataGenerator(rotation_range=15, fill_mode="nearest")

# model
vgg = VGG16(weights="imagenet",
            include_top=False,
            input_tensor=Input(shape=(224, 224, 3)))

model = vgg.output
model = AveragePooling2D(pool_size=(4, 4))(model)
model = Flatten()(model)
model = Dense(64, activation="relu")(model)
model = Dropout(0.5)(model)
model = Dense(2, activation="softmax")(model)

model = Model(inputs=vgg.input, outputs=model)

for layer in vgg.layers:
    layer.trainable = False

# compile
예제 #8
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def train_data(cluster):
      train_dir = os.path.sep.join([config.DATASET_DIR, cluster, config.TRAIN])
      validation_dir = os.path.sep.join([config.DATASET_DIR, cluster, config.VAL])
      sp_counted = len(os.listdir(train_dir))
      image_size = 280

      vgg_conv = VGG16(weights='imagenet', 
                        include_top=False, 
                        input_shape=(image_size, image_size, 3))

      for layer in vgg_conv.layers[:-4]:
            layer.trainable = False

      for layer in vgg_conv.layers:
            print(layer, layer.trainable)

      # Create the model
      model = models.Sequential()

      # Add the vgg convolutional base model
      model.add(vgg_conv)

      # Add new layers
      model.add(layers.Flatten())
      model.add(layers.Dense(1024, activation='relu'))
      model.add(layers.Dropout(0.5))
      model.add(layers.Dense(sp_counted, activation='softmax'))

      # Show a summary of the model. Check the number of trainable parameters
      model.summary()

      train_datagen = ImageDataGenerator(
            rescale=1./255,
            rotation_range=20,
            width_shift_range=0.2,
            height_shift_range=0.2,
            horizontal_flip=True,
            fill_mode='nearest'
            )
      
      validation_datagen = ImageDataGenerator(rescale=1./255)

      # Change the batchsize according to system RAM
      train_batchsize = 8
      val_batchsize = 8

      # Data Generator for Training data
      train_generator = train_datagen.flow_from_directory(
            train_dir,
            target_size=(image_size, image_size),
            batch_size=train_batchsize,
            class_mode='categorical'
            )
      
      # Data Generator for Validation data
      validation_generator = validation_datagen.flow_from_directory(
            validation_dir,
            target_size=(image_size, image_size),
            batch_size=val_batchsize,
            class_mode='categorical',
            shuffle=False)

      # Compile the model
      model.compile(loss='categorical_crossentropy',
                  optimizer=optimizers.RMSprop(lr=1e-4),
                  metrics=['acc'])

      # Train the Model
      history = model.fit_generator(
            train_generator,
            steps_per_epoch=2*train_generator.samples/train_generator.batch_size,
            epochs=config.EPOCH,
            validation_data=validation_generator,
            validation_steps=validation_generator.samples/validation_generator.batch_size,
            verbose=1)

      model.save(os.path.sep.join([config.MODEL_PATH, cluster+'.h5']))

      score = model.evaluate_generator(
            validation_generator,
            steps=validation_generator.samples/validation_generator.batch_size
      )
      print('Loss \t\t:',score[0])
      print('Accuracy \t:',score[1]*100,'%')

      return history
예제 #9
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sys.path.append('../utils')

from Utils import Utils

from tensorflow.keras.applications import VGG16
from tensorflow.keras.models import Model
from tensorflow.keras.layers import GlobalAveragePooling2D, Dense, Dropout
from tensorflow.keras.callbacks import ModelCheckpoint, EarlyStopping, TensorBoard

WIDTH = 202
HEIGHT = 280
BATCH = 32

train_generator, val_generator, test_generator = Utils.get_generators(target_size=(WIDTH, HEIGHT), batch_size=BATCH)

vgg16 = VGG16(include_top=False, weights="imagenet", input_shape=(WIDTH, HEIGHT, 3))

for layer in vgg16.layers:
    layer.trainable = False

x = GlobalAveragePooling2D()(vgg16.output)
x = Dense(254, activation='relu')(x)
x = Dropout(.5)(x)
x = Dense(254, activation='relu')(x)
x = Dropout(.5)(x)
x = Dense(11, activation='softmax')(x)

model = Model(inputs=vgg16.input, outputs=x)
model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])

callbacks = [
예제 #10
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train_generator = train_datagen.flow_from_directory(
       'StanfordDogs/train',
       target_size=(150, 150),
       batch_size=5,
       class_mode='categorical')

test_datagen = ImageDataGenerator(rescale=1./255)

test_generator = test_datagen.flow_from_directory(
       'StanfordDogs/test',
       target_size=(150, 150),
       batch_size=5,       #현재 데이터5보다 데이터가 많아야 함
       class_mode='categorical')

transfer_model = VGG16(weights='imagenet', include_top=False, input_shape=(150, 150, 3))
transfer_model.trainable = False
transfer_model.summary()

finetune_model = models.Sequential()
finetune_model.add(transfer_model)
finetune_model.add(Flatten())
finetune_model.add(Dense(64, activation='relu'))
finetune_model.add(Dense(3, activation='softmax'))  #3 부분이 분류개수
finetune_model.summary()

finetune_model.compile(loss='categorical_crossentropy', optimizer=optimizers.Adam(learning_rate=0.0002), metrics=['accuracy'])

MODEL_DIR = './modelDogs/'
if not os.path.exists(MODEL_DIR):
    os.mkdir(MODEL_DIR)
예제 #11
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                                      validation_split=0.2)
validation_datagen = ImageDataGenerator(rescale=1. / 255)

train_generator = training_datagen.flow_from_directory(
    TRAINING_DIR,
    target_size=(256, 256),
    batch_size=32,
    class_mode='categorical',
    subset='training')

valid_generator = training_datagen.flow_from_directory(TRAINING_DIR,
                                                       target_size=(256, 256),
                                                       batch_size=32,
                                                       subset='validation')

vgg16 = VGG16(weights="imagenet", include_top=False, input_shape=(256, 256, 3))
vgg16.trainable = False

model = Sequential()
model.add(vgg16)
model.add(Flatten())
model.add(Dense(256))
model.add(BatchNormalization())
model.add(Activation('relu'))
model.add(Dense(4, activation="softmax"))

#3. 컴파일, 훈련
model.compile(loss='categorical_crossentropy',
              optimizer='adam',
              metrics=['acc'])
예제 #12
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 def __init__(self):
     #Initialize all necessary models
     self.feature_extractor = VGG16(weights="imagenet", include_top=False)
     self.model = pickle.load(open("Logistic.pickle", "rb"))
     self.labels = pd.read_csv("labels.csv")
train_generator_bottleneck = datagen.flow_from_directory(
    train_data_dir,
    target_size=(img_width, img_height),
    batch_size=batch_size_small,
    class_mode=None,
    shuffle=False)

validation_generator_bottleneck = datagen.flow_from_directory(
    validation_data_dir,
    target_size=(img_width, img_height),
    batch_size=batch_size_small,
    class_mode=None,
    shuffle=False)

model_vgg16 = VGG16(input_shape=(img_width, img_height, 3),
                    include_top=False,
                    weights='imagenet',
                    pooling="max")

bottleneck_features_train = model_vgg16.predict_generator(
    train_generator_bottleneck, train_samples // batch_size, verbose=1)
np.save(open('./models/vgg16_bottleneck_features_train.npy', 'wb'),
        bottleneck_features_train)

bottleneck_features_validation = model_vgg16.predict_generator(
    validation_generator_bottleneck,
    validation_samples // batch_size,
    verbose=1)
np.save(open('./models/vgg16_bottleneck_features_validation.npy', 'wb'),
        bottleneck_features_validation)

train_data = np.load(open('./models/vgg16_bottleneck_features_train.npy',
예제 #14
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import pickle
import random
import os
from sklearn.preprocessing import LabelEncoder
from tensorflow.keras.applications import VGG16
from tensorflow.keras.applications.vgg16 import preprocess_input
from tensorflow.keras.preprocessing.image import img_to_array, load_img
import numpy as np
from imutils import paths
from transfer_learning_via_DL.cnn_as_feature_extractor.scripts import config

# %%

model = VGG16(weights='imagenet', include_top=False)
le = None

# %%

split = 'evaluation'
for split in (config.TRAIN, config.TEST, config.VAL):
    p = os.path.sep.join([config.BASE_PATH, split])
    imagePaths = list(paths.list_images(p))
    random.shuffle(imagePaths)
    labels = [p.split(os.path.sep)[-2] for p in imagePaths]
    if le is None:
        le = LabelEncoder()
        le.fit(labels)
    csvPath = os.path.sep.join([config.BASE_CSV_PATH, '{}.csv'.format(split)])
    csv = open(csvPath, 'w')
    for b, i in enumerate(range(0, len(imagePaths), config.BATCH_SIZE)):
        print("[INFO] processing batch {}/{}".format(
def ssd_300(
    weights,
    image_size,
    n_classes,
    mode='training',
    l2_regularization=0.0005,
    min_scale=None,
    max_scale=None,
    scales=None,
    aspect_ratios_global=None,
    aspect_ratios_per_layer=[[1.0, 2.0, 0.5],
                             [1.0, 2.0, 0.5, 3.0, 1.0/3.0],
                             [1.0, 2.0, 0.5, 3.0, 1.0/3.0],
                             [1.0, 2.0, 0.5, 3.0, 1.0/3.0],
                             [1.0, 2.0, 0.5],
                             [1.0, 2.0, 0.5]],
    two_boxes_for_ar1=True,
    steps=[8, 16, 32, 64, 100, 300],
    offsets=None,
    clip_boxes=False,
    variances=[0.1, 0.1, 0.2, 0.2],
    coords='centroids',
    normalize_coords=True,
    confidence_thresh=0.01,
    iou_threshold=0.45,
    top_k=200,
    nms_max_output_size=400,
    return_predictor_sizes=False):
    '''
    Build a Keras model with SSD300 architecture, see references.

    The base network is a reduced atrous VGG-16, extended by the SSD architecture,
    as described in the paper.

    Most of the arguments that this function takes are only needed for the anchor
    box layers. In case you're training the network, the parameters passed here must
    be the same as the ones used to set up `SSDBoxEncoder`. In case you're loading
    trained weights, the parameters passed here must be the same as the ones used
    to produce the trained weights.

    Some of these arguments are explained in more detail in the documentation of the
    `SSDBoxEncoder` class.

    Note: Requires Keras v2.0 or later. Currently works only with the
    TensorFlow backend (v1.0 or later).

    Arguments:
        image_size (tuple): The input image size in the format `(height, width, channels)`.
        n_classes (int): The number of positive classes, e.g. 20 for Pascal VOC, 80 for MS COCO.
        mode (str, optional): One of 'training', 'inference' and 'inference_fast'. In 'training' mode,
            the model outputs the raw prediction tensor, while in 'inference' and 'inference_fast' modes,
            the raw predictions are decoded into absolute coordinates and filtered via confidence thresholding,
            non-maximum suppression, and top-k filtering. The difference between latter two modes is that
            'inference' follows the exact procedure of the original Caffe implementation, while
            'inference_fast' uses a faster prediction decoding procedure.
        l2_regularization (float, optional): The L2-regularization rate. Applies to all convolutional layers.
            Set to zero to deactivate L2-regularization.
        min_scale (float, optional): The smallest scaling factor for the size of the anchor boxes as a fraction
            of the shorter side of the input images.
        max_scale (float, optional): The largest scaling factor for the size of the anchor boxes as a fraction
            of the shorter side of the input images. All scaling factors between the smallest and the
            largest will be linearly interpolated. Note that the second to last of the linearly interpolated
            scaling factors will actually be the scaling factor for the last predictor layer, while the last
            scaling factor is used for the second box for aspect ratio 1 in the last predictor layer
            if `two_boxes_for_ar1` is `True`.
        scales (list, optional): A list of floats containing scaling factors per convolutional predictor layer.
            This list must be one element longer than the number of predictor layers. The first `k` elements are the
            scaling factors for the `k` predictor layers, while the last element is used for the second box
            for aspect ratio 1 in the last predictor layer if `two_boxes_for_ar1` is `True`. This additional
            last scaling factor must be passed either way, even if it is not being used. If a list is passed,
            this argument overrides `min_scale` and `max_scale`. All scaling factors must be greater than zero.
        aspect_ratios_global (list, optional): The list of aspect ratios for which anchor boxes are to be
            generated. This list is valid for all prediction layers.
        aspect_ratios_per_layer (list, optional): A list containing one aspect ratio list for each prediction layer.
            This allows you to set the aspect ratios for each predictor layer individually, which is the case for the
            original SSD300 implementation. If a list is passed, it overrides `aspect_ratios_global`.
        two_boxes_for_ar1 (bool, optional): Only relevant for aspect ratio lists that contain 1. Will be ignored otherwise.
            If `True`, two anchor boxes will be generated for aspect ratio 1. The first will be generated
            using the scaling factor for the respective layer, the second one will be generated using
            geometric mean of said scaling factor and next bigger scaling factor.
        steps (list, optional): `None` or a list with as many elements as there are predictor layers. The elements can be
            either ints/floats or tuples of two ints/floats. These numbers represent for each predictor layer how many
            pixels apart the anchor box center points should be vertically and horizontally along the spatial grid over
            the image. If the list contains ints/floats, then that value will be used for both spatial dimensions.
            If the list contains tuples of two ints/floats, then they represent `(step_height, step_width)`.
            If no steps are provided, then they will be computed such that the anchor box center points will form an
            equidistant grid within the image dimensions.
        offsets (list, optional): `None` or a list with as many elements as there are predictor layers. The elements can be
            either floats or tuples of two floats. These numbers represent for each predictor layer how many
            pixels from the top and left boarders of the image the top-most and left-most anchor box center points should be
            as a fraction of `steps`. The last bit is important: The offsets are not absolute pixel values, but fractions
            of the step size specified in the `steps` argument. If the list contains floats, then that value will
            be used for both spatial dimensions. If the list contains tuples of two floats, then they represent
            `(vertical_offset, horizontal_offset)`. If no offsets are provided, then they will default to 0.5 of the step size.
        clip_boxes (bool, optional): If `True`, clips the anchor box coordinates to stay within image boundaries.
        variances (list, optional): A list of 4 floats >0. The anchor box offset for each coordinate will be divided by
            its respective variance value.
        coords (str, optional): The box coordinate format to be used internally by the model (i.e. this is not the input format
            of the ground truth labels). Can be either 'centroids' for the format `(cx, cy, w, h)` (box center coordinates, width,
            and height), 'minmax' for the format `(xmin, xmax, ymin, ymax)`, or 'corners' for the format `(xmin, ymin, xmax, ymax)`.
        normalize_coords (bool, optional): Set to `True` if the model is supposed to use relative instead of absolute coordinates,
            i.e. if the model predicts box coordinates within [0,1] instead of absolute coordinates.
        subtract_mean (array-like, optional): `None` or an array-like object of integers or floating point values
            of any shape that is broadcast-compatible with the image shape. The elements of this array will be
            subtracted from the image pixel intensity values. For example, pass a list of three integers
            to perform per-channel mean normalization for color images.
        divide_by_stddev (array-like, optional): `None` or an array-like object of non-zero integers or
            floating point values of any shape that is broadcast-compatible with the image shape. The image pixel
            intensity values will be divided by the elements of this array. For example, pass a list
            of three integers to perform per-channel standard deviation normalization for color images.
        swap_channels (list, optional): Either `False` or a list of integers representing the desired order in which the input
            image channels should be swapped.
        confidence_thresh (float, optional): A float in [0,1), the minimum classification confidence in a specific
            positive class in order to be considered for the non-maximum suppression stage for the respective class.
            A lower value will result in a larger part of the selection process being done by the non-maximum suppression
            stage, while a larger value will result in a larger part of the selection process happening in the confidence
            thresholding stage.
        iou_threshold (float, optional): A float in [0,1]. All boxes that have a Jaccard similarity of greater than `iou_threshold`
            with a locally maximal box will be removed from the set of predictions for a given class, where 'maximal' refers
            to the box's confidence score.
        top_k (int, optional): The number of highest scoring predictions to be kept for each batch item after the
            non-maximum suppression stage.
        nms_max_output_size (int, optional): The maximal number of predictions that will be left over after the NMS stage.
        return_predictor_sizes (bool, optional): If `True`, this function not only returns the model, but also
            a list containing the spatial dimensions of the predictor layers. This isn't strictly necessary since
            you can always get their sizes easily via the Keras API, but it's convenient and less error-prone
            to get them this way. They are only relevant for training anyway (SSDBoxEncoder needs to know the
            spatial dimensions of the predictor layers), for inference you don't need them.

    Returns:
        model: The Keras SSD300 model.
        predictor_sizes (optional): A Numpy array containing the `(height, width)` portion
            of the output tensor shape for each convolutional predictor layer. During
            training, the generator function needs this in order to transform
            the ground truth labels into tensors of identical structure as the
            output tensors of the model, which is in turn needed for the cost
            function.

    References:
        https://arxiv.org/abs/1512.02325v5
    '''

    n_predictor_layers = 6 # The number of predictor conv layers in the network is 6 for the original SSD300.
    # n_classes += 1 # Account for the background class.
    l2_reg = l2_regularization # Make the internal name shorter.
    img_height, img_width, img_channels = image_size[0], image_size[1], image_size[2]

    ############################################################################
    # Get a few exceptions out of the way.
    ############################################################################

    if aspect_ratios_global is None and aspect_ratios_per_layer is None:
        raise ValueError("`aspect_ratios_global` and `aspect_ratios_per_layer` cannot both be None. At least one needs to be specified.")
    if aspect_ratios_per_layer:
        if len(aspect_ratios_per_layer) != n_predictor_layers:
            raise ValueError("It must be either aspect_ratios_per_layer is None or len(aspect_ratios_per_layer) == {}, but len(aspect_ratios_per_layer) == {}.".format(n_predictor_layers, len(aspect_ratios_per_layer)))

    if (min_scale is None or max_scale is None) and scales is None:
        raise ValueError("Either `min_scale` and `max_scale` or `scales` need to be specified.")
    if scales:
        if len(scales) != n_predictor_layers+1:
            raise ValueError("It must be either scales is None or len(scales) == {}, but len(scales) == {}.".format(n_predictor_layers+1, len(scales)))
    else: # If no explicit list of scaling factors was passed, compute the list of scaling factors from `min_scale` and `max_scale`
        scales = np.linspace(min_scale, max_scale, n_predictor_layers+1)

    if len(variances) != 4:
        raise ValueError("4 variance values must be pased, but {} values were received.".format(len(variances)))
    variances = np.array(variances)
    if np.any(variances <= 0):
        raise ValueError("All variances must be >0, but the variances given are {}".format(variances))

    if (not (steps is None)) and (len(steps) != n_predictor_layers):
        raise ValueError("You must provide at least one step value per predictor layer.")

    if (not (offsets is None)) and (len(offsets) != n_predictor_layers):
        raise ValueError("You must provide at least one offset value per predictor layer.")

    ############################################################################
    # Compute the anchor box parameters.
    ############################################################################

    # Set the aspect ratios for each predictor layer. These are only needed for the anchor box layers.
    if aspect_ratios_per_layer:
        aspect_ratios = aspect_ratios_per_layer
    else:
        aspect_ratios = [aspect_ratios_global] * n_predictor_layers

    # Compute the number of boxes to be predicted per cell for each predictor layer.
    # We need this so that we know how many channels the predictor layers need to have.
    if aspect_ratios_per_layer:
        n_boxes = []
        for ar in aspect_ratios_per_layer:
            if (1 in ar) & two_boxes_for_ar1:
                n_boxes.append(len(ar) + 1) # +1 for the second box for aspect ratio 1
            else:
                n_boxes.append(len(ar))
    else: # If only a global aspect ratio list was passed, then the number of boxes is the same for each predictor layer
        if (1 in aspect_ratios_global) & two_boxes_for_ar1:
            n_boxes = len(aspect_ratios_global) + 1
        else:
            n_boxes = len(aspect_ratios_global)
        n_boxes = [n_boxes] * n_predictor_layers

    if steps is None:
        steps = [None] * n_predictor_layers
    if offsets is None:
        offsets = [None] * n_predictor_layers



    backbone = VGG16(include_top=False, input_shape=image_size, weights=weights)

    conv4_3 = backbone.get_layer('block4_conv3').output
    conv5_3 = backbone.get_layer('block5_conv3').output
    pool5 = MaxPooling2D(pool_size=(3, 3), strides=(1, 1), padding='same', name='pool5')(conv5_3)

    fc6 = Conv2D(1024, (3, 3), dilation_rate=(6, 6), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='fc6')(pool5)

    fc7 = Conv2D(1024, (1, 1), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='fc7')(fc6)

    conv6_1 = Conv2D(256, (1, 1), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv6_1')(fc7)
    conv6_1 = ZeroPadding2D(padding=((1, 1), (1, 1)), name='conv6_padding')(conv6_1)
    conv6_2 = Conv2D(512, (3, 3), strides=(2, 2), activation='relu', padding='valid', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv6_2')(conv6_1)

    conv7_1 = Conv2D(128, (1, 1), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv7_1')(conv6_2)
    conv7_1 = ZeroPadding2D(padding=((1, 1), (1, 1)), name='conv7_padding')(conv7_1)
    conv7_2 = Conv2D(256, (3, 3), strides=(2, 2), activation='relu', padding='valid', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv7_2')(conv7_1)

    conv8_1 = Conv2D(128, (1, 1), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv8_1')(conv7_2)
    conv8_2 = Conv2D(256, (3, 3), strides=(1, 1), activation='relu', padding='valid', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv8_2')(conv8_1)

    conv9_1 = Conv2D(128, (1, 1), activation='relu', padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv9_1')(conv8_2)
    conv9_2 = Conv2D(256, (3, 3), strides=(1, 1), activation='relu', padding='valid', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv9_2')(conv9_1)

    # Feed conv4_3 into the L2 normalization layer
    # conv4_3_norm = L2Normalization(gamma_init=20, name='conv4_3_norm')(conv4_3)

    conv4_3_norm = LayerNormalization(name='conv4_3_norm')(conv4_3)

    ### Build the convolutional predictor layers on top of the base network

    # We precidt `n_classes` confidence values for each box, hence the confidence predictors have depth `n_boxes * n_classes`
    # Output shape of the confidence layers: `(batch, height, width, n_boxes * n_classes)`
    conv4_3_norm_mbox_conf = Conv2D(n_boxes[0] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv4_3_norm_mbox_conf')(conv4_3_norm)
    fc7_mbox_conf = Conv2D(n_boxes[1] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='fc7_mbox_conf')(fc7)
    conv6_2_mbox_conf = Conv2D(n_boxes[2] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv6_2_mbox_conf')(conv6_2)
    conv7_2_mbox_conf = Conv2D(n_boxes[3] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv7_2_mbox_conf')(conv7_2)
    conv8_2_mbox_conf = Conv2D(n_boxes[4] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv8_2_mbox_conf')(conv8_2)
    conv9_2_mbox_conf = Conv2D(n_boxes[5] * n_classes, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv9_2_mbox_conf')(conv9_2)
    # We predict 4 box coordinates for each box, hence the localization predictors have depth `n_boxes * 4`
    # Output shape of the localization layers: `(batch, height, width, n_boxes * 4)`
    conv4_3_norm_mbox_loc = Conv2D(n_boxes[0] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv4_3_norm_mbox_loc')(conv4_3_norm)
    fc7_mbox_loc = Conv2D(n_boxes[1] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='fc7_mbox_loc')(fc7)
    conv6_2_mbox_loc = Conv2D(n_boxes[2] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv6_2_mbox_loc')(conv6_2)
    conv7_2_mbox_loc = Conv2D(n_boxes[3] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv7_2_mbox_loc')(conv7_2)
    conv8_2_mbox_loc = Conv2D(n_boxes[4] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv8_2_mbox_loc')(conv8_2)
    conv9_2_mbox_loc = Conv2D(n_boxes[5] * 4, (3, 3), padding='same', kernel_initializer='he_normal', kernel_regularizer=l2(l2_reg), name='conv9_2_mbox_loc')(conv9_2)

    ### Generate the anchor boxes (called "priors" in the original Caffe/C++ implementation, so I'll keep their layer names)

    # Output shape of anchors: `(batch, height, width, n_boxes, 8)`
    conv4_3_norm_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[0], next_scale=scales[1], aspect_ratios=aspect_ratios[0],
                                             two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[0], this_offsets=offsets[0], clip_boxes=clip_boxes,
                                             variances=variances, coords=coords, normalize_coords=normalize_coords, name='conv4_3_norm_mbox_priorbox')(conv4_3_norm_mbox_loc)
    fc7_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[1], next_scale=scales[2], aspect_ratios=aspect_ratios[1],
                                    two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[1], this_offsets=offsets[1], clip_boxes=clip_boxes,
                                    variances=variances, coords=coords, normalize_coords=normalize_coords, name='fc7_mbox_priorbox')(fc7_mbox_loc)
    conv6_2_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[2], next_scale=scales[3], aspect_ratios=aspect_ratios[2],
                                        two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[2], this_offsets=offsets[2], clip_boxes=clip_boxes,
                                        variances=variances, coords=coords, normalize_coords=normalize_coords, name='conv6_2_mbox_priorbox')(conv6_2_mbox_loc)
    conv7_2_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[3], next_scale=scales[4], aspect_ratios=aspect_ratios[3],
                                        two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[3], this_offsets=offsets[3], clip_boxes=clip_boxes,
                                        variances=variances, coords=coords, normalize_coords=normalize_coords, name='conv7_2_mbox_priorbox')(conv7_2_mbox_loc)
    conv8_2_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[4], next_scale=scales[5], aspect_ratios=aspect_ratios[4],
                                        two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[4], this_offsets=offsets[4], clip_boxes=clip_boxes,
                                        variances=variances, coords=coords, normalize_coords=normalize_coords, name='conv8_2_mbox_priorbox')(conv8_2_mbox_loc)
    conv9_2_mbox_priorbox = AnchorBoxes(img_height, img_width, this_scale=scales[5], next_scale=scales[6], aspect_ratios=aspect_ratios[5],
                                        two_boxes_for_ar1=two_boxes_for_ar1, this_steps=steps[5], this_offsets=offsets[5], clip_boxes=clip_boxes,
                                        variances=variances, coords=coords, normalize_coords=normalize_coords, name='conv9_2_mbox_priorbox')(conv9_2_mbox_loc)

    ### Reshape

    # Reshape the class predictions, yielding 3D tensors of shape `(batch, height * width * n_boxes, n_classes)`
    # We want the classes isolated in the last axis to perform softmax on them
    conv4_3_norm_mbox_conf_reshape = Reshape((-1, n_classes), name='conv4_3_norm_mbox_conf_reshape')(conv4_3_norm_mbox_conf)
    fc7_mbox_conf_reshape = Reshape((-1, n_classes), name='fc7_mbox_conf_reshape')(fc7_mbox_conf)
    conv6_2_mbox_conf_reshape = Reshape((-1, n_classes), name='conv6_2_mbox_conf_reshape')(conv6_2_mbox_conf)
    conv7_2_mbox_conf_reshape = Reshape((-1, n_classes), name='conv7_2_mbox_conf_reshape')(conv7_2_mbox_conf)
    conv8_2_mbox_conf_reshape = Reshape((-1, n_classes), name='conv8_2_mbox_conf_reshape')(conv8_2_mbox_conf)
    conv9_2_mbox_conf_reshape = Reshape((-1, n_classes), name='conv9_2_mbox_conf_reshape')(conv9_2_mbox_conf)
    # Reshape the box predictions, yielding 3D tensors of shape `(batch, height * width * n_boxes, 4)`
    # We want the four box coordinates isolated in the last axis to compute the smooth L1 loss
    conv4_3_norm_mbox_loc_reshape = Reshape((-1, 4), name='conv4_3_norm_mbox_loc_reshape')(conv4_3_norm_mbox_loc)
    fc7_mbox_loc_reshape = Reshape((-1, 4), name='fc7_mbox_loc_reshape')(fc7_mbox_loc)
    conv6_2_mbox_loc_reshape = Reshape((-1, 4), name='conv6_2_mbox_loc_reshape')(conv6_2_mbox_loc)
    conv7_2_mbox_loc_reshape = Reshape((-1, 4), name='conv7_2_mbox_loc_reshape')(conv7_2_mbox_loc)
    conv8_2_mbox_loc_reshape = Reshape((-1, 4), name='conv8_2_mbox_loc_reshape')(conv8_2_mbox_loc)
    conv9_2_mbox_loc_reshape = Reshape((-1, 4), name='conv9_2_mbox_loc_reshape')(conv9_2_mbox_loc)
    # Reshape the anchor box tensors, yielding 3D tensors of shape `(batch, height * width * n_boxes, 8)`
    conv4_3_norm_mbox_priorbox_reshape = Reshape((-1, 8), name='conv4_3_norm_mbox_priorbox_reshape')(conv4_3_norm_mbox_priorbox)
    fc7_mbox_priorbox_reshape = Reshape((-1, 8), name='fc7_mbox_priorbox_reshape')(fc7_mbox_priorbox)
    conv6_2_mbox_priorbox_reshape = Reshape((-1, 8), name='conv6_2_mbox_priorbox_reshape')(conv6_2_mbox_priorbox)
    conv7_2_mbox_priorbox_reshape = Reshape((-1, 8), name='conv7_2_mbox_priorbox_reshape')(conv7_2_mbox_priorbox)
    conv8_2_mbox_priorbox_reshape = Reshape((-1, 8), name='conv8_2_mbox_priorbox_reshape')(conv8_2_mbox_priorbox)
    conv9_2_mbox_priorbox_reshape = Reshape((-1, 8), name='conv9_2_mbox_priorbox_reshape')(conv9_2_mbox_priorbox)

    ### Concatenate the predictions from the different layers

    # Axis 0 (batch) and axis 2 (n_classes or 4, respectively) are identical for all layer predictions,
    # so we want to concatenate along axis 1, the number of boxes per layer
    # Output shape of `mbox_conf`: (batch, n_boxes_total, n_classes)
    mbox_conf = Concatenate(axis=1, name='mbox_conf')([conv4_3_norm_mbox_conf_reshape,
                                                       fc7_mbox_conf_reshape,
                                                       conv6_2_mbox_conf_reshape,
                                                       conv7_2_mbox_conf_reshape,
                                                       conv8_2_mbox_conf_reshape,
                                                       conv9_2_mbox_conf_reshape])

    # Output shape of `mbox_loc`: (batch, n_boxes_total, 4)
    mbox_loc = Concatenate(axis=1, name='mbox_loc')([conv4_3_norm_mbox_loc_reshape,
                                                     fc7_mbox_loc_reshape,
                                                     conv6_2_mbox_loc_reshape,
                                                     conv7_2_mbox_loc_reshape,
                                                     conv8_2_mbox_loc_reshape,
                                                     conv9_2_mbox_loc_reshape])

    # Output shape of `mbox_priorbox`: (batch, n_boxes_total, 8)
    mbox_priorbox = Concatenate(axis=1, name='mbox_priorbox')([conv4_3_norm_mbox_priorbox_reshape,
                                                               fc7_mbox_priorbox_reshape,
                                                               conv6_2_mbox_priorbox_reshape,
                                                               conv7_2_mbox_priorbox_reshape,
                                                               conv8_2_mbox_priorbox_reshape,
                                                               conv9_2_mbox_priorbox_reshape])

    # The box coordinate predictions will go into the loss function just the way they are,
    # but for the class predictions, we'll apply a softmax activation layer first
    mbox_conf_softmax = Activation('softmax', name='mbox_conf_softmax')(mbox_conf)

    # Concatenate the class and box predictions and the anchors to one large predictions vector
    # Output shape of `predictions`: (batch, n_boxes_total, n_classes + 4 + 8)
    predictions = Concatenate(axis=2, name='predictions')([mbox_conf_softmax, mbox_loc, mbox_priorbox])

    if mode == 'training':
        model = Model(inputs=backbone.input, outputs=predictions)
    elif mode == 'inference':
        decoded_predictions = DecodeDetections(confidence_thresh=confidence_thresh,
                                               iou_threshold=iou_threshold,
                                               top_k=top_k,
                                               nms_max_output_size=nms_max_output_size,
                                               coords=coords,
                                               normalize_coords=normalize_coords,
                                               img_height=img_height,
                                               img_width=img_width,
                                               name='decoded_predictions')(predictions)
        model = Model(inputs=backbone.input, outputs=decoded_predictions)
    elif mode == 'inference_fast':
        decoded_predictions = DecodeDetectionsFast(confidence_thresh=confidence_thresh,
                                                   iou_threshold=iou_threshold,
                                                   top_k=top_k,
                                                   nms_max_output_size=nms_max_output_size,
                                                   coords=coords,
                                                   normalize_coords=normalize_coords,
                                                   img_height=img_height,
                                                   img_width=img_width,
                                                   name='decoded_predictions')(predictions)
        model = Model(inputs=backbone.input, outputs=decoded_predictions)
    else:
        raise ValueError("`mode` must be one of 'training', 'inference' or 'inference_fast', but received '{}'.".format(mode))

    if return_predictor_sizes:
        predictor_sizes = np.array([conv4_3_norm_mbox_conf.get_shape()[1:3],
                                     fc7_mbox_conf.get_shape()[1:3],
                                     conv6_2_mbox_conf.get_shape()[1:3],
                                     conv7_2_mbox_conf.get_shape()[1:3],
                                     conv8_2_mbox_conf.get_shape()[1:3],
                                     conv9_2_mbox_conf.get_shape()[1:3]])
        return model, preprocess_input,predictor_sizes
    else:
        return model, preprocess_input