def main(save_to):
batch_size = 365
feature_maps = [6, 16]
mlp_hiddens = [120, 84]
conv_sizes = [5, 5]
pool_sizes = [2, 2]
image_size = (28, 28)
output_size = 10
# The above are from LeCun's paper. The blocks example had:
# feature_maps = [20, 50]
# mlp_hiddens = [500]
# Use ReLUs everywhere and softmax for the final prediction
conv_activations = [Rectifier() for _ in feature_maps]
mlp_activations = [Rectifier() for _ in mlp_hiddens] + [Softmax()]
convnet = LeNet(conv_activations, 1, image_size,
filter_sizes=zip(conv_sizes, conv_sizes),
feature_maps=feature_maps,
pooling_sizes=zip(pool_sizes, pool_sizes),
top_mlp_activations=mlp_activations,
top_mlp_dims=mlp_hiddens + [output_size],
border_mode='valid',
weights_init=Uniform(width=.2),
biases_init=Constant(0))
# We push initialization config to set different initialization schemes
# for convolutional layers.
convnet.push_initialization_config()
convnet.layers[0].weights_init = Uniform(width=.2)
convnet.layers[1].weights_init = Uniform(width=.09)
convnet.top_mlp.linear_transformations[0].weights_init = Uniform(width=.08)
convnet.top_mlp.linear_transformations[1].weights_init = Uniform(width=.11)
convnet.initialize()
logging.info("Input dim: {} {} {}".format(
*convnet.children[0].get_dim('input_')))
for i, layer in enumerate(convnet.layers):
if isinstance(layer, Activation):
logging.info("Layer {} ({})".format(
i, layer.__class__.__name__))
else:
logging.info("Layer {} ({}) dim: {} {} {}".format(
i, layer.__class__.__name__, *layer.get_dim('output')))
x = tensor.tensor4('features')
# Normalize input and apply the convnet
probs = convnet.apply(x)
cg = ComputationGraph([probs])
outs = VariableFilter(
roles=[OUTPUT], bricks=[Convolutional, Linear])(cg.variables)
# Create an interior activation model
model = Model([probs] + outs)
# Load it with trained parameters
params = load_parameters(open(save_to, 'rb'))
model.set_parameter_values(params)
algorithm = MaximumActivationSearch(outputs=outs)
# Use the mnist test set, unshuffled
mnist_test = MNIST(("test",), sources=['features'])
mnist_test_stream = DataStream.default_stream(
mnist_test,
iteration_scheme=SequentialScheme(
mnist_test.num_examples, batch_size))
extensions = [Timing(),
FinishAfter(after_n_epochs=1),
DataStreamMonitoring(
[],
mnist_test_stream,
prefix="test"),
Checkpoint("maxact.tar"),
ProgressBar(),
Printing()]
main_loop = MainLoop(
algorithm,
mnist_test_stream,
model=model,
extensions=extensions)
main_loop.run()
examples = mnist_test.get_example_stream()
example = examples.get_data(0)[0]
layers = convnet.layers
for output, record in algorithm.maximum_activations.items():
layer = get_brick(output)
activations, indices, snapshots = (
r.get_value() if r else None for r in record[1:])
filmstrip = Filmstrip(
example.shape[-2:], (indices.shape[1], indices.shape[0]),
background='blue')
if layer in layers:
fieldmap = layerarray_fieldmap(layers[0:layers.index(layer) + 1])
for unit in range(indices.shape[1]):
for index in range(100):
mask = make_mask(example.shape[-2:], fieldmap, numpy.clip(
snapshots[index, unit, :, :], 0, numpy.inf))
imagenum = indices[index, unit, 0]
filmstrip.set_image((unit, index),
examples.get_data(imagenum)[0], mask)
else:
for unit in range(indices.shape[1]):
for index in range(100):
imagenum = indices[index, unit]
filmstrip.set_image((unit, index),
examples.get_data(imagenum)[0])
filmstrip.save(layer.name + '_maxact.jpg')
