cnn.py

""" Convolutional Neural Network
"""

# Installing Theano
# pip install --upgrade --no-deps git+git://github.com/Theano/Theano.git

# Installing Tensorflow
# Install Tensorflow from the website: https://www.tensorflow.org/versions/r0.12/get_started/os_setup.html

# Installing Keras
# pip install --upgrade keras

# Part 1 - Building the CNN

# Importing the Keras libraries and packages
from keras.models import Sequential
from keras.layers import Convolution2D
from keras.layers import MaxPooling2D
from keras.layers import Flatten
from keras.layers import Dense
from keras.preprocessing.image import ImageDataGenerator


def main():
    # Initialising the CNN
    classifier = Sequential()

    # Step 1 - Convolution
    classifier.add(Convolution2D(32, 3, 3, input_shape=(64, 64, 3), activation='relu'))

    # Step 2 - Pooling
    classifier.add(MaxPooling2D(pool_size=(2, 2)))

    # Adding a second convolutional layer
    classifier.add(Convolution2D(32, 3, 3, activation='relu'))
    classifier.add(MaxPooling2D(pool_size=(2, 2)))

    # Step 3 - Flattening
    classifier.add(Flatten())

    # Step 4 - Full connection
    classifier.add(Dense(output_dim=128, activation='relu'))
    classifier.add(Dense(output_dim=1, activation='sigmoid'))

    # Compiling the CNN
    classifier.compile(optimizer='adam', loss='binary_crossentropy', metrics=['accuracy'])

    # Part 2 - Fitting the CNN to the images

    train_datagen = ImageDataGenerator(rescale=1. / 255,
                                       shear_range=0.2,
                                       zoom_range=0.2,
                                       horizontal_flip=True)

    test_datagen = ImageDataGenerator(rescale=1. / 255)

    training_set = train_datagen.flow_from_directory('dataset/training_set',
                                                     target_size=(64, 64),
                                                     batch_size=32,
                                                     class_mode='binary')

    test_set = test_datagen.flow_from_directory('dataset/test_set',
                                                target_size=(64, 64),
                                                batch_size=32,
                                                class_mode='binary')

    classifier.fit_generator(training_set,
                             samples_per_epoch=8000,
                             nb_epoch=25,
                             validation_data=test_set,
                             nb_val_samples=2000)


if __name__ == '__main__':
    main()