def main():
# Read MNIST dataset (x_raw contains the original images):
(x_raw, y_raw), (x_raw_test, y_raw_test), min_, max_ = load_mnist(raw=True)
n_train = np.shape(x_raw)[0]
num_selection = 5000
random_selection_indices = np.random.choice(n_train, num_selection)
x_raw = x_raw[random_selection_indices]
y_raw = y_raw[random_selection_indices]
# Poison training data
perc_poison = 0.33
(is_poison_train, x_poisoned_raw,
y_poisoned_raw) = generate_backdoor(x_raw, y_raw, perc_poison)
x_train, y_train = preprocess(x_poisoned_raw, y_poisoned_raw)
# Add channel axis:
x_train = np.expand_dims(x_train, axis=3)
# Poison test data
(is_poison_test, x_poisoned_raw_test,
y_poisoned_raw_test) = generate_backdoor(x_raw_test, y_raw_test,
perc_poison)
x_test, y_test = preprocess(x_poisoned_raw_test, y_poisoned_raw_test)
# Add channel axis:
x_test = np.expand_dims(x_test, axis=3)
# Shuffle training data so poison is not together
n_train = np.shape(y_train)[0]
shuffled_indices = np.arange(n_train)
np.random.shuffle(shuffled_indices)
x_train = x_train[shuffled_indices]
y_train = y_train[shuffled_indices]
is_poison_train = is_poison_train[shuffled_indices]
# Create Keras convolutional neural network - basic architecture from Keras examples
# Source here: https://github.com/keras-team/keras/blob/master/examples/mnist_cnn.py
model = Sequential()
model.add(
Conv2D(32,
kernel_size=(3, 3),
activation="relu",
input_shape=x_train.shape[1:]))
model.add(Conv2D(64, (3, 3), activation="relu"))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.25))
model.add(Flatten())
model.add(Dense(128, activation="relu"))
model.add(Dropout(0.5))
model.add(Dense(10, activation="softmax"))
model.compile(loss="categorical_crossentropy",
optimizer="adam",
metrics=["accuracy"])
classifier = KerasClassifier(model=model, clip_values=(min_, max_))
classifier.fit(x_train, y_train, nb_epochs=30, batch_size=128)
# Evaluate the classifier on the test set
preds = np.argmax(classifier.predict(x_test), axis=1)
acc = np.sum(preds == np.argmax(y_test, axis=1)) / y_test.shape[0]
print("\nTest accuracy: %.2f%%" % (acc * 100))
# Evaluate the classifier on poisonous data
preds = np.argmax(classifier.predict(x_test[is_poison_test]), axis=1)
acc = np.sum(preds == np.argmax(y_test[is_poison_test],
axis=1)) / y_test[is_poison_test].shape[0]
print(
"\nPoisonous test set accuracy (i.e. effectiveness of poison): %.2f%%"
% (acc * 100))
# Evaluate the classifier on clean data
preds = np.argmax(classifier.predict(x_test[is_poison_test == 0]), axis=1)
acc = np.sum(preds == np.argmax(y_test[
is_poison_test == 0], axis=1)) / y_test[is_poison_test == 0].shape[0]
print("\nClean test set accuracy: %.2f%%" % (acc * 100))
# Calling poisoning defence:
defence = ActivationDefence(classifier, x_train, y_train)
# End-to-end method:
print("------------------- Results using size metric -------------------")
print(defence.get_params())
defence.detect_poison(nb_clusters=2, nb_dims=10, reduce="PCA")
# Evaluate method when ground truth is known:
is_clean = is_poison_train == 0
confusion_matrix = defence.evaluate_defence(is_clean)
print("Evaluation defence results for size-based metric: ")
jsonObject = json.loads(confusion_matrix)
for label in jsonObject:
print(label)
pprint.pprint(jsonObject[label])
# Visualize clusters:
print("Visualize clusters")
sprites_by_class = defence.visualize_clusters(x_train, "mnist_poison_demo")
# Show plots for clusters of class 5
n_class = 5
try:
import matplotlib.pyplot as plt
plt.imshow(sprites_by_class[n_class][0])
plt.title("Class " + str(n_class) + " cluster: 0")
plt.show()
plt.imshow(sprites_by_class[n_class][1])
plt.title("Class " + str(n_class) + " cluster: 1")
plt.show()
except ImportError:
print(
"matplotlib not installed. For this reason, cluster visualization was not displayed"
)
# Try again using distance analysis this time:
print(
"------------------- Results using distance metric -------------------"
)
print(defence.get_params())
defence.detect_poison(nb_clusters=2,
nb_dims=10,
reduce="PCA",
cluster_analysis="distance")
confusion_matrix = defence.evaluate_defence(is_clean)
print("Evaluation defence results for distance-based metric: ")
jsonObject = json.loads(confusion_matrix)
for label in jsonObject:
print(label)
pprint.pprint(jsonObject[label])
# Other ways to invoke the defence:
kwargs = {"nb_clusters": 2, "nb_dims": 10, "reduce": "PCA"}
defence.cluster_activations(**kwargs)
kwargs = {"cluster_analysis": "distance"}
defence.analyze_clusters(**kwargs)
defence.evaluate_defence(is_clean)
kwargs = {"cluster_analysis": "smaller"}
defence.analyze_clusters(**kwargs)
defence.evaluate_defence(is_clean)
print("done :) ")
def main():
# Read MNIST dataset (x_raw contains the original images):
(x_raw, y_raw), (x_raw_test, y_raw_test), min_, max_ = load_mnist(raw=True)
n_train = np.shape(x_raw)[0]
num_selection = 5000
random_selection_indices = np.random.choice(n_train, num_selection)
x_raw = x_raw[random_selection_indices]
y_raw = y_raw[random_selection_indices]
# Poison training data
perc_poison = .33
(is_poison_train, x_poisoned_raw, y_poisoned_raw) = generate_backdoor(x_raw, y_raw, perc_poison)
x_train, y_train = preprocess(x_poisoned_raw, y_poisoned_raw)
# Add channel axis:
x_train = np.expand_dims(x_train, axis=3)
# Poison test data
(is_poison_test, x_poisoned_raw_test, y_poisoned_raw_test) = generate_backdoor(x_raw_test, y_raw_test, perc_poison)
x_test, y_test = preprocess(x_poisoned_raw_test, y_poisoned_raw_test)
# Add channel axis:
x_test = np.expand_dims(x_test, axis=3)
# Shuffle training data so poison is not together
n_train = np.shape(y_train)[0]
shuffled_indices = np.arange(n_train)
np.random.shuffle(shuffled_indices)
x_train = x_train[shuffled_indices]
y_train = y_train[shuffled_indices]
is_poison_train = is_poison_train[shuffled_indices]
# Create Keras convolutional neural network - basic architecture from Keras examples
# Source here: https://github.com/keras-team/keras/blob/master/examples/mnist_cnn.py
k.set_learning_phase(1)
model = Sequential()
model.add(Conv2D(32, kernel_size=(3, 3), activation='relu', input_shape=x_train.shape[1:]))
model.add(Conv2D(64, (3, 3), activation='relu'))
model.add(MaxPooling2D(pool_size=(2, 2)))
model.add(Dropout(0.25))
model.add(Flatten())
model.add(Dense(128, activation='relu'))
model.add(Dropout(0.5))
model.add(Dense(10, activation='softmax'))
model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
classifier = KerasClassifier((min_, max_), model=model)
classifier.fit(x_train, y_train, nb_epochs=30, batch_size=128)
# Evaluate the classifier on the test set
preds = np.argmax(classifier.predict(x_test), axis=1)
acc = np.sum(preds == np.argmax(y_test, axis=1)) / y_test.shape[0]
print("\nTest accuracy: %.2f%%" % (acc * 100))
# Evaluate the classifier on poisonous data
preds = np.argmax(classifier.predict(x_test[is_poison_test]), axis=1)
acc = np.sum(preds == np.argmax(y_test[is_poison_test], axis=1)) / y_test[is_poison_test].shape[0]
print("\nPoisonous test set accuracy (i.e. effectiveness of poison): %.2f%%" % (acc * 100))
# Evaluate the classifier on clean data
preds = np.argmax(classifier.predict(x_test[is_poison_test == 0]), axis=1)
acc = np.sum(preds == np.argmax(y_test[is_poison_test == 0], axis=1)) / y_test[is_poison_test == 0].shape[0]
print("\nClean test set accuracy: %.2f%%" % (acc * 100))
# Calling poisoning defence:
defence = ActivationDefence(classifier, x_train, y_train, verbose=True)
# End-to-end method:
print("------------------- Results using size metric -------------------")
print(defence.get_params())
defence.detect_poison(n_clusters=2, ndims=10, reduce="PCA")
# Evaluate method when ground truth is known:
is_clean = (is_poison_train == 0)
confusion_matrix = defence.evaluate_defence(is_clean)
print("Evaluation defence results for size-based metric: ")
pprint.pprint(confusion_matrix)
# Visualize clusters:
print("Visualize clusters")
defence.visualize_clusters(x_train, 'mnist_poison_demo')
# Try again using distance analysis this time:
print("------------------- Results using distance metric -------------------")
print(defence.get_params())
defence.detect_poison(n_clusters=2, ndims=10, reduce="PCA", cluster_analysis='distance')
confusion_matrix = defence.evaluate_defence(is_clean)
print("Evaluation defence results for distance-based metric: ")
pprint.pprint(confusion_matrix)
# Other ways to invoke the defence:
defence.cluster_activations(n_clusters=2, ndims=10, reduce='PCA')
defence.analyze_clusters(cluster_analysis='distance')
defence.evaluate_defence(is_clean)
defence.analyze_clusters(cluster_analysis='smaller')
defence.evaluate_defence(is_clean)
print("done :) ")