diff --git a/examples/cifar10_nasnet.py b/examples/cifar10_nasnet.py new file mode 100644 index 0000000..8eee651 --- /dev/null +++ b/examples/cifar10_nasnet.py @@ -0,0 +1,97 @@ +""" +Adapted from keras example cifar10_cnn.py +Train NASNet-CIFAR on the CIFAR10 small images dataset. + +GPU run command with Theano backend (with TensorFlow, the GPU is automatically used): + THEANO_FLAGS=mode=FAST_RUN,device=gpu,floatX=float32 python cifar10_nasnet.py +""" +from __future__ import print_function +from keras.datasets import cifar10 +from keras.preprocessing.image import ImageDataGenerator +from keras.utils import np_utils +from keras.callbacks import ModelCheckpoint +from keras.callbacks import ReduceLROnPlateau +from keras.callbacks import CSVLogger +from keras_contrib.applications.nasnet import NASNetCIFAR + +import numpy as np + + +weights_file = 'NASNet-CIFAR-10.h5' +lr_reducer = ReduceLROnPlateau(factor=np.sqrt(0.5), cooldown=0, patience=5, min_lr=0.5e-6) +csv_logger = CSVLogger('NASNet-CIFAR-10.csv') +model_checkpoint = ModelCheckpoint(weights_file, monitor='val_predictions_acc', save_best_only=True, + save_weights_only=True, mode='max') + +batch_size = 128 +nb_classes = 10 +nb_epoch = 200 +data_augmentation = True + +# input image dimensions +img_rows, img_cols = 32, 32 +# The CIFAR10 images are RGB. +img_channels = 3 + +# The data, shuffled and split between train and test sets: +(X_train, y_train), (X_test, y_test) = cifar10.load_data() + +# Convert class vectors to binary class matrices. +Y_train = np_utils.to_categorical(y_train, nb_classes) +Y_test = np_utils.to_categorical(y_test, nb_classes) + +X_train = X_train.astype('float32') +X_test = X_test.astype('float32') + +# subtract mean and normalize +mean_image = np.mean(X_train, axis=0) +X_train -= mean_image +X_test -= mean_image +X_train /= 128. +X_test /= 128. + +# For training, the auxilary branch must be used to correctly train NASNet +model = NASNetCIFAR((img_rows, img_cols, img_channels), dropout=0.5, + use_auxilary_branch=True) +model.compile(loss=['categorical_crossentropy', 'categorical_crossentropy'], + optimizer='adam', + loss_weights=[1.0, 0.4], + metrics=['accuracy']) + +if not data_augmentation: + print('Not using data augmentation.') + model.fit(X_train, Y_train, + batch_size=batch_size, + nb_epoch=nb_epoch, + validation_data=(X_test, Y_test), + shuffle=True, + callbacks=[lr_reducer, csv_logger, model_checkpoint]) +else: + print('Using real-time data augmentation.') + # This will do preprocessing and realtime data augmentation: + datagen = ImageDataGenerator( + featurewise_center=False, # set input mean to 0 over the dataset + samplewise_center=False, # set each sample mean to 0 + featurewise_std_normalization=False, # divide inputs by std of the dataset + samplewise_std_normalization=False, # divide each input by its std + zca_whitening=False, # apply ZCA whitening + rotation_range=0, # randomly rotate images in the range (degrees, 0 to 180) + width_shift_range=0.1, # randomly shift images horizontally (fraction of total width) + height_shift_range=0.1, # randomly shift images vertically (fraction of total height) + horizontal_flip=True, # randomly flip images + vertical_flip=False) # randomly flip images + + # Compute quantities required for featurewise normalization + # (std, mean, and principal components if ZCA whitening is applied). + datagen.fit(X_train) + + # Fit the model on the batches generated by datagen.flow(). + model.fit_generator(datagen.flow(X_train, Y_train, batch_size=batch_size), + steps_per_epoch=X_train.shape[0] // batch_size, + validation_data=(X_test, Y_test), + epochs=nb_epoch, verbose=2, + callbacks=[lr_reducer, csv_logger, model_checkpoint]) + +scores = model.evaluate(X_test, Y_test, batch_size=batch_size) +for score, metric_name in zip(scores, model.metrics_names): + print("%s : %0.4f" % (metric_name, score)) diff --git a/keras_contrib/applications/nasnet.py b/keras_contrib/applications/nasnet.py index cddc682..072172d 100644 --- a/keras_contrib/applications/nasnet.py +++ b/keras_contrib/applications/nasnet.py @@ -215,7 +215,7 @@ def NASNet(input_shape=None, auxilary_x = Activation('relu')(auxilary_x) auxilary_x = GlobalAveragePooling2D()(auxilary_x) - auxilary_x = Dense(classes, activation='softmax')(auxilary_x) + auxilary_x = Dense(classes, activation='softmax', name='aux_predictions')(auxilary_x) x, p0 = _reduction_A(x, p, filters * filters_multiplier ** 2, id='reduce_%d' % (2 * nb_blocks))