コード例 #1
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    def build_model(self):
        l2_regularization_kernel = 1e-5

        # Input Layer
        input = layers.Input(shape=(self.state_size,), name='input_states')

        # Hidden Layers
        model = layers.Dense(units=300, kernel_regularizer=regularizers.l2(l2_regularization_kernel))(input)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(1e-2)(model)

        model = layers.Dense(units=400, kernel_regularizer=regularizers.l2(l2_regularization_kernel))(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(1e-2)(model)

        model = layers.Dense(units=200, kernel_regularizer=regularizers.l2(l2_regularization_kernel))(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(1e-2)(model)

        # Our output layer - a fully connected layer
        output = layers.Dense(units=self.action_size, activation='tanh', kernel_regularizer=regularizers.l2(l2_regularization_kernel),
                               kernel_initializer=initializers.RandomUniform(minval=-3e-3, maxval=3e-3), name='output_actions')(model)

        # Keras model
        self.model = models.Model(inputs=input, outputs=output)

        # Define loss and optimizer
        action_gradients = layers.Input(shape=(self.action_size,))
        loss = K.mean(-action_gradients * output)
        optimizer = optimizers.Adam(lr=1e-4)

        update_operation = optimizer.get_updates(params=self.model.trainable_weights, loss=loss)
        self.train_fn = K.function(inputs=[self.model.input, action_gradients, K.learning_phase()],
            outputs=[], updates=update_operation)
コード例 #2
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    def build_model(self):
        l2_kernel_regularization = 1e-5

        # Define input layers
        input_states = layers.Input(shape=(self.state_size, ),
                                    name='input_states')
        input_actions = layers.Input(shape=(self.action_size, ),
                                     name='input_actions')

        # Hidden layers for states
        model_states = layers.Dense(
            units=32,
            kernel_regularizer=regularizers.l2(l2_kernel_regularization))(
                input_states)
        model_states = layers.BatchNormalization()(model_states)
        model_states = layers.LeakyReLU(1e-2)(model_states)

        model_states = layers.Dense(
            units=64,
            kernel_regularizer=regularizers.l2(l2_kernel_regularization))(
                model_states)
        model_states = layers.BatchNormalization()(model_states)
        model_states = layers.LeakyReLU(1e-2)(model_states)

        # Hidden layers for actions
        model_actions = layers.Dense(
            units=64,
            kernel_regularizer=regularizers.l2(l2_kernel_regularization))(
                input_actions)
        model_actions = layers.BatchNormalization()(model_actions)
        model_actions = layers.LeakyReLU(1e-2)(model_actions)

        # Both models merge here
        model = layers.add([model_states, model_actions])

        # Fully connected and batch normalization
        model = layers.Dense(units=32,
                             kernel_regularizer=regularizers.l2(
                                 l2_kernel_regularization))(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(1e-2)(model)

        # Q values / output layer
        Q_values = layers.Dense(
            units=1,
            activation=None,
            kernel_regularizer=regularizers.l2(l2_kernel_regularization),
            kernel_initializer=initializers.RandomUniform(minval=-5e-3,
                                                          maxval=5e-3),
            name='output_Q_values')(model)

        # Keras wrap the model
        self.model = models.Model(inputs=[input_states, input_actions],
                                  outputs=Q_values)
        optimizer = optimizers.Adam(lr=1e-2)
        self.model.compile(optimizer=optimizer, loss='mse')
        action_gradients = K.gradients(Q_values, input_actions)
        self.get_action_gradients = K.function(
            inputs=[*self.model.input, K.learning_phase()],
            outputs=action_gradients)
コード例 #3
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    def build_model(self):
        """Build an actor (policy) network that maps states -> actions."""
        # Define input layer (states)
        states = layers.Input(shape=(self.state_size, ), name='states')
        '''# Add hidden layers
        net = layers.Dense(units=32, activation='relu')(states)
        net = layers.Dense(units=64, activation='relu')(net)
        net = layers.Dense(units=32, activation='relu')(net)
        
        # Try different layer sizes, activations, add batch normalization, regularizers, etc.

        # Add final output layer with sigmoid activation
        raw_actions = layers.Dense(units=self.action_size, activation='sigmoid',
            name='raw_actions')(net)
        '''
        ###################################
        # Add hidden layers
        net = layers.Dense(units=400,
                           kernel_regularizer=regularizers.l2(1e-6))(states)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)
        net = layers.Dense(units=300,
                           kernel_regularizer=regularizers.l2(1e-6))(net)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)

        # Add final output layer with sigmoid activation
        raw_actions = layers.Dense(
            units=self.action_size,
            activation='sigmoid',
            name='raw_actions',
            kernel_initializer=initializers.RandomUniform(minval=-0.003,
                                                          maxval=0.003))(net)
        #######################################

        # Scale [0, 1] output for each action dimension to proper range
        actions = layers.Lambda(lambda x:
                                (x * self.action_range) + self.action_low,
                                name='actions')(raw_actions)

        # Create Keras model
        self.model = models.Model(inputs=states, outputs=actions)

        # Define loss function using action value (Q value) gradients
        action_gradients = layers.Input(shape=(self.action_size, ))
        loss = K.mean(-action_gradients * actions)

        # Incorporate any additional losses here (e.g. from regularizers)

        # Define optimizer and training function
        optimizer = optimizers.Adam(lr=1e-6)
        updates_op = optimizer.get_updates(params=self.model.trainable_weights,
                                           loss=loss)
        self.train_fn = K.function(
            inputs=[self.model.input, action_gradients,
                    K.learning_phase()],
            outputs=[],
            updates=updates_op)
コード例 #4
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    def build_model(self):
        """Build an actor (policy) network that maps states -> actions."""
        # Define input layer (states)
        states = layers.Input(shape=(self.state_size, ), name='states')

        #--------- copy from DDPG quadcopter -----------
        net = layers.Dense(units=400)(states)
        # net = layers.BatchNormalization()(net)
        net = layers.Activation("relu")(net)
        net = layers.Dense(units=200)(net)
        # net = layers.BatchNormalization()(net)
        net = layers.Activation("relu")(net)
        actions = layers.Dense(units=self.action_size,
                               activation='softmax',
                               name='actions',
                               kernel_initializer=initializers.RandomUniform(
                                   minval=-1, maxval=1))(net)

        # actions = layers.Dense(units=self.action_size, activation='sigmoid', name='actions',
        # 		kernel_initializer=initializers.RandomUniform(minval=-0.001, maxval=0.001))(net)

        # Add hidden layers
        # net = layers.Dense(units=16,activation=activations.sigmoid)(states)
        # net = layers.BatchNormalization()(net)

        # net = layers.Dense(units=16,activation=activations.sigmoid)(net)
        # net = layers.BatchNormalization()(net)

        # net = layers.Dense(units=128,activation=activations.relu)(net)
        # net = layers.BatchNormalization()(net)

        # Add final output layer with sigmoid activation
        # actions = layers.Dense(units=self.action_size, activation='linear', # sigmoid
        # 	name='raw_actions' )(net)

        # Scale [0, 1] output for each action dimension to proper range
        #         actions = layers.Lambda(lambda x: (x * self.action_range) + self.action_low,
        #             name='actions')(raw_actions)

        # Create Keras model
        self.model = models.Model(inputs=states, outputs=actions)
        action_gradients = layers.Input(shape=(self.action_size, ))
        loss = K.mean(-action_gradients * actions)

        # Define optimizer and training function
        optimizer = optimizers.Adam(lr=.0001)
        updates_op = optimizer.get_updates(params=self.model.trainable_weights,
                                           loss=loss)
        self.train_fn = K.function(
            inputs=[self.model.input, action_gradients,
                    K.learning_phase()],
            outputs=[],
            updates=updates_op)
コード例 #5
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    def build_model(self):
        #Define input layers
        inputStates = layers.Input(shape=(self.state_size, ),
                                   name='inputStates')
        inputActions = layers.Input(shape=(self.action_size, ),
                                    name='inputActions')

        # Hidden layers for states
        modelS = layers.Dense(units=128, activation='linear')(inputStates)
        modelS = layers.BatchNormalization()(modelS)
        modelS = layers.LeakyReLU(0.01)(modelS)
        modelS = layers.Dropout(0.3)(modelS)

        modelS = layers.Dense(units=256, activation='linear')(modelS)
        modelS = layers.BatchNormalization()(modelS)
        modelS = layers.LeakyReLU(0.01)(modelS)
        modelS = layers.Dropout(0.3)(modelS)

        modelA = layers.Dense(units=256, activation='linear')(inputActions)
        modelA = layers.LeakyReLU(0.01)(modelA)
        modelA = layers.BatchNormalization()(modelA)
        modelA = layers.Dropout(0.5)(modelA)

        #Merging the models
        model = layers.add([modelS, modelA])
        model = layers.Dense(units=256, activation='linear')(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(0.01)(model)

        #Q Layer
        Qvalues = layers.Dense(units=1, activation=None,
                               name='outputQvalues')(model)

        #Keras model
        self.model = models.Model(inputs=[inputStates, inputActions],
                                  outputs=Qvalues)
        optimizer = optimizers.Adam()
        self.model.compile(optimizer=optimizer, loss='mse')
        actionGradients = K.gradients(Qvalues, inputActions)
        self.get_action_gradients = K.function(
            inputs=[*self.model.input, K.learning_phase()],
            outputs=actionGradients)
コード例 #6
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    def build_model(self): 
        states = layers.Input(shape=(self.state_size,), name='inputStates')

        # Hidden Layers
        model = layers.Dense(units=128, activation='linear')(states)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(0.01)(model)
        model = layers.Dropout(0.3)(model)
        
        model = layers.Dense(units=256, activation='linear')(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(0.01)(model)
        model = layers.Dropout(0.3)(model)

        model = layers.Dense(units=512, activation='linear')(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(0.01)(model)
        model = layers.Dropout(0.3)(model)

        model = layers.Dense(units=128, activation='linear')(model)
        model = layers.BatchNormalization()(model)
        model = layers.LeakyReLU(0.01)(model)
        model = layers.Dropout(0.3)(model)

        output = layers.Dense(
            units=self.action_size, 
            activation='tanh', 
            kernel_regularizer=regularizers.l2(0.01),
            name='outputActions')(model)

        #Keras
        self.model = models.Model(inputs=states, outputs=output)

        #Definint Optimizer
        actionGradients = layers.Input(shape=(self.action_size,))
        loss = K.mean(-actionGradients * output)
        optimizer = optimizers.Adam()
        update_operation = optimizer.get_updates(params=self.model.trainable_weights, loss=loss)
        self.train_fn = K.function(
            inputs=[self.model.input, actionGradients, K.learning_phase()],
            outputs=[], 
            updates=update_operation)
コード例 #7
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    def __init__(self, input_tensor, losses, input_range=(0, 255), wrt_tensor=None, norm_grads=True):
        """Creates an optimizer that minimizes weighted loss function.

        Args:
            input_tensor: An input tensor of shape: `(samples, channels, image_dims...)` if `image_data_format=
                channels_first` or `(samples, image_dims..., channels)` if `image_data_format=channels_last`.
            losses: List of ([Loss](vis.losses#Loss), weight) tuples.
            input_range: Specifies the input range as a `(min, max)` tuple. This is used to rescale the
                final optimized input to the given range. (Default value=(0, 255))
            wrt_tensor: Short for, with respect to. This instructs the optimizer that the aggregate loss from `losses`
                should be minimized with respect to `wrt_tensor`.
                `wrt_tensor` can be any tensor that is part of the model graph. Default value is set to None
                which means that loss will simply be minimized with respect to `input_tensor`.
            norm_grads: True to normalize gradients. Normalization avoids very small or large gradients and ensures
                a smooth gradient gradient descent process. If you want the actual gradient
                (for example, visualizing attention), set this to false.
        """
        self.input_tensor = input_tensor
        self.input_range = input_range
        self.loss_names = []
        self.loss_functions = []
        self.wrt_tensor = self.input_tensor if wrt_tensor is None else wrt_tensor

        overall_loss = None
        for loss, weight in losses:
            # Perf optimization. Don't build loss function with 0 weight.
            if weight != 0:
                loss_fn = weight * loss.build_loss()
                overall_loss = loss_fn if overall_loss is None else overall_loss + loss_fn
                self.loss_names.append(loss.name)
                self.loss_functions.append(loss_fn)

        # Compute gradient of overall with respect to `wrt` tensor.
        grads = K.gradients(overall_loss, self.wrt_tensor)[0]
        if norm_grads:
            grads = grads / (K.sqrt(K.mean(K.square(grads))) + K.epsilon())

        # The main function to compute various quantities in optimization loop.
        self.compute_fn = K.function([self.input_tensor, K.learning_phase()],
                                     self.loss_functions + [overall_loss, grads, self.wrt_tensor])
コード例 #8
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def gradCAM(model, dog_x, class_idx):
    model_class_output = model.output[:, class_idx]
    print('model_class_output shape', model_class_output.shape)
    last_conv_layer = model.get_layer('block5_conv3')

    grads_list = K.gradients(model_class_output, last_conv_layer.output)
    grads = grads_list[0]
    # grads shape: (?, 14, 14, 512)

    pooled_grads = K.mean(grads, axis=(0, 1, 2))
    # pooled_grads shape: (512,)

    iterate = K.function(inputs=[model.input],
                         outputs=[pooled_grads, last_conv_layer.output[0]])
    pooled_grads_value, conv_layer_output_value = iterate([dog_x])
    # conv_layer_output_value shape: (14, 14, 512)

    for i in range(last_conv_layer.filters):
        conv_layer_output_value[:, :, i] *= pooled_grads_value[i]

    heatmap = np.mean(conv_layer_output_value, axis=-1)
    # heatmap shape: (14, 14)
    heatmap = normalize_heatmap(heatmap)
    return heatmap
コード例 #9
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def generate_pattern(model, layer_name, filter_index, steps, learning_rate, size=224):
    layer_output = model.get_layer(layer_name).output
    loss = K.mean(layer_output[:, :, :, filter_index])

    # obtain the gradient of the loss with respect to the model's input image
    grads_list = K.gradients(loss, model.input)
    grads = grads_list[0]

    # gradient normalization trick
    grads /= (K.sqrt(K.mean(K.square(grads))) + EPSILON)

    # fetch loss and normalized-gradients for a given input
    iterate = K.function(inputs=[model.input], outputs=[loss, grads])

    # loss maximization via stochastic gradient descent
    input_img_data = np.random.random((1, size, size, 3)) * 20 + 128  # start from gray image with random noise
    for i in range(steps):
        loss_value, grads_value = iterate([input_img_data])
        print('@{:-4d}: {:.4f}'.format(i, loss_value))
        # gradient ascent: adjust the input image in the direction that maximizes the loss
        input_img_data += grads_value * learning_rate

    img_tensor = input_img_data[0]
    return tensor_to_image(img_tensor)
コード例 #10
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# in the form of total variation loss for spatial smootheness.
def total_variation_loss(x):
    a = K.square(x[:, :height-1, :width-1, :] - x[:, 1:, :width-1, :])
    b = K.square(x[:, :height-1, :width-1, :] - x[:, :height-1, 1:, :])
    return K.sum(K.pow(a + b, 1.25))

loss += total_variation_weight * total_variation_loss(combination_image)

# Define the gradients of the combination image w.r.t. the loss function
grads = K.gradients(loss, combination_image)

# Class that calculates loss and gradients on one pass. We do this becayse
# optimizer requires two separate functions for those but that is inefficient.
outputs = [loss]
outputs += grads
f_outputs = K.function([combination_image], outputs)
#print(f_outputs)
def eval_loss_and_grads(x):
    x = x.reshape((1, height, width, 3))
    outs = f_outputs([x])
    loss_value = outs[0]
    grad_values = outs[1].flatten().astype('float64')
    return loss_value, grad_values

class Evaluator(object):

    def __init__(self):
        self.loss_value = None
        self.grads_values = None

    def loss(self, x):
コード例 #11
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    def build_model(self):
        """Build a critic (value) network that maps (state, action) pairs -> Q-values."""
        # Define input layers
        states = layers.Input(shape=(self.state_size, ), name='states')
        actions = layers.Input(shape=(self.action_size, ), name='actions')

        # Add hidden layer(s) for state pathway
        net_states = layers.Dense(
            units=32,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(states)
        net_states = layers.BatchNormalization()(net_states)
        net_states = layers.LeakyReLU(1e-2)(net_states)

        net_states = layers.Dense(
            units=64,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(net_states)
        net_states = layers.BatchNormalization()(net_states)
        net_states = layers.LeakyReLU(1e-2)(net_states)

        net_states = layers.Dense(
            units=128,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(net_states)
        net_states = layers.BatchNormalization()(net_states)
        net_states = layers.LeakyReLU(1e-2)(net_states)

        # Add hidden layer(s) for action pathway
        net_actions = layers.Dense(
            units=32,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(actions)
        net_actions = layers.BatchNormalization()(net_actions)
        net_actions = layers.LeakyReLU(1e-2)(net_actions)

        net_actions = layers.Dense(
            units=64,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(net_actions)
        net_actions = layers.BatchNormalization()(net_actions)
        net_actions = layers.LeakyReLU(1e-2)(net_actions)

        net_actions = layers.Dense(
            units=128,
            activation='relu',
            use_bias=False,
            kernel_regularizer=regularizers.l2(0.01),
            activity_regularizer=regularizers.l1(0.01))(net_actions)
        net_actions = layers.BatchNormalization()(net_actions)
        net_actions = layers.LeakyReLU(1e-2)(net_actions)

        # Try different layer sizes, activations, add batch normalization, regularizers, etc.

        # Combine state and action pathways
        net = layers.Add()([net_states, net_actions])
        net = layers.Activation('relu')(net)

        # Add more layers to the combined network if needed

        # Add final output layer to prduce action values (Q values)
        Q_values = layers.Dense(units=1, name='q_values')(net)

        # Create Keras model
        self.model = models.Model(inputs=[states, actions], outputs=Q_values)

        # Define optimizer and compile model for training with built-in loss function
        optimizer = optimizers.Adam()
        self.model.compile(optimizer=optimizer, loss='mse')

        # Compute action gradients (derivative of Q values w.r.t. to actions)
        action_gradients = K.gradients(Q_values, actions)

        # Define an additional function to fetch action gradients (to be used by actor model)
        self.get_action_gradients = K.function(
            inputs=[*self.model.input, K.learning_phase()],
            outputs=action_gradients)
コード例 #12
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for filter_index in range(0, 50):
    print('start')
    # we build a loss function that maximizes the activation
    # of the nth filter of the layer considered
    layer_output = layer_dict[layer_name].output

    loss = K.mean(layer_output[:, :, :, filter_index])

    # we compute the gradient of the input picture wrt this loss
    grads = K.gradients(loss, input_img)[0]

    # normalization trick: we normalize the gradient by its L2 norm
    grads = normalize(grads)

    # this function returns the loss and grads given the input picture
    iterate = K.function([input_img], [loss, grads])

    # step size for gradient ascent
    step = 1.

    # we start from a gray image with some random noise
    input_img_data = np.random.random((1, resolution, resolution, 1))
    input_img_data = (input_img_data - 0.5) * 20 + 128

    # we run gradient ascent for 20 steps
    for i in range(20):
        loss_value, grads_value = iterate([input_img_data])
        input_img_data += grads_value * step

        print('Current loss value:', loss_value)
        if loss_value <= 0.:
コード例 #13
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#define input shape
input_shape = (360, 480)

#construct graph
inputs = tf.placeholder("float", shape=(1, input_shape[0], input_shape[1], 3))
logits, end_points = segnet(inputs)
sess = tf.Session()
saver = tf.train.Saver()
saver.restore(sess, 'weights/segnet_tf.ckpt')
K.set_session(sess)
K.manual_variable_initialization(True)
nimage = np.asarray([Image.open('ouzel.jpg').resize(input_shape).getdata()
                     ]).astype(np.float32)
nimage = np.reshape(nimage, (input_shape[0], input_shape[1], 3))
nimage = np.expand_dims(nimage, 0)
fn = K.function([inputs], [logits])
a = fn([nimage])

#visualize filters
name = 'conv1_1_D'
name = 'conv4_2_bn'
name = 'relu_2'
name = 'conv4_2'
name = 'conv3_1_D'
name = 'relu5_3'
idx = 8
#img = visualize_activation_tf(inputs,end_points,name, filter_indices=idx, tv_weight=.0,lp_norm_weight=0., input_modifiers=[Jitter(0.05)])
#img = visualize_activation_tf(inputs,end_points,name, filter_indices=idx, max_iter=1800, act_max_weight=0.1,tv_weight=0.01,lp_norm_weight=10000, input_modifiers=[Jitter(16)], verbose=True)
img = visualize_activation_tf(inputs,
                              end_points,
                              name,
コード例 #14
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    def build_model(self):
        kernel_l2_reg = 1e-5
        """Build an actor (policy) network that maps states -> actions."""
        # Define input layer (states)
        states = layers.Input(shape=(self.state_size, ), name='states')

        # size_repeat = 30
        # block_size = size_repeat*self.state_size
        # print("Actor block size = {}".format(block_size))
        #
        # net = layers.concatenate([states]*size_repeat)
        # # net = layers.Dense(block_size,
        # #                    # kernel_initializer=initializers.RandomNormal(mean=1.0, stddev=0.1),
        # #                    #  bias_initializer=initializers.RandomNormal(mean=0.0, stddev=0.01),
        # #                    activation=None,
        # #                    use_bias=False)(states)
        # net = layers.BatchNormalization()(net)
        # net = layers.Dropout(0.2)(net)
        # # net = layers.LeakyReLU(1e-2)(net)
        #
        # for _ in range(5):
        #     net = res_block(net, block_size)

        # Add hidden layers
        net = layers.Dense(
            units=300,
            kernel_regularizer=regularizers.l2(kernel_l2_reg))(states)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)

        net = layers.Dense(
            units=400, kernel_regularizer=regularizers.l2(kernel_l2_reg))(net)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)

        net = layers.Dense(
            units=200, kernel_regularizer=regularizers.l2(kernel_l2_reg))(net)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)

        # Try different layer sizes, activations, add batch normalization, regularizers, etc.

        # # Add final output layer with sigmoid activation
        # raw_actions = layers.Dense(units=self.action_size,
        #                            activation='sigmoid',
        #                            # kernel_regularizer=regularizers.l2(kernel_l2_reg),
        #                            kernel_initializer=initializers.RandomUniform(minval=-3e-3, maxval=3e-3),
        #                            # bias_initializer=initializers.RandomUniform(minval=-3e-3, maxval=3e-3),
        #                            name='raw_actions')(net)
        #
        # # Scale [0, 1] output for each action dimension to proper range
        # actions = layers.Lambda(lambda x: (x * self.action_range) + self.action_low, name='actions')(raw_actions)

        actions = layers.Dense(
            units=self.action_size,
            activation='tanh',
            kernel_regularizer=regularizers.l2(kernel_l2_reg),
            kernel_initializer=initializers.RandomUniform(minval=-3e-3,
                                                          maxval=3e-3),
            name='actions')(net)

        # Create Keras model
        self.model = models.Model(inputs=states, outputs=actions)

        # Define loss function using action value (Q value) gradients
        action_gradients = layers.Input(shape=(self.action_size, ))
        loss = K.mean(-action_gradients * actions)

        # Incorporate any additional losses here (e.g. from regularizers)

        # Define optimizer and training function
        optimizer = optimizers.Adam(lr=1e-4)

        updates_op = optimizer.get_updates(params=self.model.trainable_weights,
                                           loss=loss)
        self.train_fn = K.function(
            inputs=[self.model.input, action_gradients,
                    K.learning_phase()],
            outputs=[],
            updates=updates_op)
コード例 #15
0
    def build_model(self):

        # Define input layers
        input_states = layers.Input(shape=(self.state_size, ),
                                    name='input_states')
        input_actions = layers.Input(shape=(self.action_size, ),
                                     name='input_actions')

        #---------- copy from DDPG quadcopter ---------
        # Add hidden layer(s) for state pathway
        net_states = layers.Dense(units=400)(input_states)
        # net_states = layers.BatchNormalization()(net_states)
        net_states = layers.Activation("relu")(net_states)

        net_states = layers.Dense(units=300)(net_states)
        net_states = layers.Activation("relu")(net_states)

        # Add hidden layer(s) for action pathway
        net_actions = layers.Dense(units=300)(input_actions)
        net_actions = layers.Activation("relu")(net_actions)

        # net_actions = layers.Dense(units=250,kernel_regularizer=regularizers.l2(1e-7))(net_actions)
        # net_actions = layers.BatchNormalization()(net_actions)
        # net_actions = layers.Activation("relu")(net_actions)

        # Combine state and action pathways
        net = layers.Add()([net_states, net_actions])
        net = layers.Activation('relu')(net)

        net = layers.Dense(units=200,
                           kernel_initializer=initializers.RandomUniform(
                               minval=-0.5, maxval=0.5))(net)
        net = layers.Activation('relu')(net)

        # Add final output layer to prduce action values (Q values)
        Q_values = layers.Dense(units=1, name='q_values')(net)

        # ---------------- Hidden layers for states ----------------
        # model_states = layers.Dense(units=32, activation=activations.sigmoid)(input_states)
        # # model_states = layers.BatchNormalization()(model_states)

        # model_states = layers.Dense(units=16, activation=activations.sigmoid)(model_states)
        # # model_states = layers.BatchNormalization()(model_states)

        # # model_states = layers.Dense(units=64)(model_states)
        # # model_states = layers.BatchNormalization()(model_states)

        # # ---------------- Hidden layers for actions ----------------
        # model_actions = layers.Dense(units=16, activation=activations.sigmoid)(input_actions)
        # # model_actions = layers.BatchNormalization()(model_actions)

        # model_actions = layers.Dense(units=16, activation=activations.sigmoid)(model_actions)
        # # model_actions = layers.BatchNormalization()(model_actions)

        # # Both models merge here
        # model = layers.add([model_states, model_actions])

        # # Fully connected and batch normalization
        # model = layers.Dense(units=8, activation=activations.sigmoid)(model)
        # # model = layers.BatchNormalization()(model)

        # # model = layers.Dense(units=64, activation=activations.relu)(model)
        # # model = layers.BatchNormalization()(model)

        # # Q values / output layer
        # Q_values = layers.Dense(units=1, name='Q_s_a')(model)
        # # model = layers.BatchNormalization()(model)

        #  Keras wrap the model
        self.model = models.Model(inputs=[input_states, input_actions],
                                  outputs=Q_values)

        optimizer = optimizers.Adam(lr=0.0001)
        self.model.compile(optimizer=optimizer, loss='mse')

        action_gradients = K.gradients(Q_values, input_actions)
        self.get_action_gradients = K.function(
            inputs=[*self.model.input, K.learning_phase()],
            outputs=action_gradients)
コード例 #16
0
    def build_model(self):
        kernel_l2_reg = 1e-5

        # Dense Options
        # units = 200,
        # activation='relu',
        # activation = None,
        # activity_regularizer=regularizers.l2(0.01),
        # kernel_regularizer=regularizers.l2(kernel_l2_reg),
        # bias_initializer=initializers.Constant(1e-2),
        # use_bias = True
        # use_bias=False
        """Build a critic (value) network that maps (state, action) pairs -> Q-values."""
        # Define input layers
        states = layers.Input(shape=(self.state_size, ), name='states')
        actions = layers.Input(shape=(self.action_size, ), name='actions')

        # size_repeat = 30
        # state_size = size_repeat*self.state_size
        # action_size = size_repeat*self.action_size
        # block_size = size_repeat*self.state_size + size_repeat*self.action_size
        # print("Critic block size = {}".format(block_size))
        #
        # net_states = layers.concatenate(size_repeat * [states])
        # net_states = layers.BatchNormalization()(net_states)
        # net_states = layers.Dropout(0.2)(net_states)
        #
        # net_actions = layers.concatenate(size_repeat * [actions])
        # net_actions = layers.BatchNormalization()(net_actions)
        # net_actions = layers.Dropout(0.2)(net_actions)
        #
        # # State pathway
        # for _ in range(3):
        #     net_states = res_block(net_states, state_size)
        #
        # # Action pathway
        # for _ in range(2):
        #     net_actions = res_block(net_actions, action_size)
        #
        # # Merge state and action pathways
        # net = layers.concatenate([net_states, net_actions])
        #
        # # Final blocks
        # for _ in range(3):
        #     net = res_block(net, block_size)

        # Add hidden layer(s) for state pathway
        net_states = layers.Dense(
            units=300,
            kernel_regularizer=regularizers.l2(kernel_l2_reg))(states)
        net_states = layers.BatchNormalization()(net_states)
        net_states = layers.LeakyReLU(1e-2)(net_states)

        net_states = layers.Dense(
            units=400,
            kernel_regularizer=regularizers.l2(kernel_l2_reg))(net_states)
        net_states = layers.BatchNormalization()(net_states)
        net_states = layers.LeakyReLU(1e-2)(net_states)

        # Add hidden layer(s) for action pathway
        net_actions = layers.Dense(
            units=400,
            kernel_regularizer=regularizers.l2(kernel_l2_reg))(actions)
        net_actions = layers.BatchNormalization()(net_actions)
        net_actions = layers.LeakyReLU(1e-2)(net_actions)

        # Merge state and action pathways
        net = layers.add([net_states, net_actions])

        net = layers.Dense(
            units=200, kernel_regularizer=regularizers.l2(kernel_l2_reg))(net)
        net = layers.BatchNormalization()(net)
        net = layers.LeakyReLU(1e-2)(net)

        # Add final output layer to prduce action values (Q values)
        Q_values = layers.Dense(
            units=1,
            activation=None,
            kernel_regularizer=regularizers.l2(kernel_l2_reg),
            kernel_initializer=initializers.RandomUniform(minval=-5e-3,
                                                          maxval=5e-3),
            # bias_initializer=initializers.RandomUniform(minval=-3e-3, maxval=3e-3),
            name='q_values')(net)

        # Create Keras model
        self.model = models.Model(inputs=[states, actions], outputs=Q_values)

        # Define optimizer and compile model for training with built-in loss function
        optimizer = optimizers.Adam(lr=1e-2)

        self.model.compile(optimizer=optimizer, loss='mse')

        # Compute action gradients (derivative of Q values w.r.t. to actions)
        action_gradients = K.gradients(Q_values, actions)

        # Define an additional function to fetch action gradients (to be used by actor model)
        self.get_action_gradients = K.function(
            inputs=[*self.model.input, K.learning_phase()],
            outputs=action_gradients)
コード例 #17
0
def main(_):
    width, height = preprocessing.image.load_img(FLAGS.target_img_path).size
    gen_img_height = 400
    gen_img_width = int(width * gen_img_height / height)

    target_x = preprocess_img(FLAGS.target_img_path, target_size=(gen_img_height, gen_img_width))
    target_img = K.constant(target_x)
    style_x = preprocess_img(FLAGS.style_img_path, target_size=(gen_img_height, gen_img_width))
    style_img = K.constant(style_x)
    combination_img = K.placeholder(shape=(1, gen_img_height, gen_img_width, 3))

    input_tensor = K.concatenate([
        target_img,
        style_img,
        combination_img
    ], axis=0)

    model = applications.vgg19.VGG19(input_tensor=input_tensor,
                                     weights='imagenet',
                                     include_top=False)
    model.summary()

    outputs_dict = dict([(layer.name, layer.output) for layer in model.layers])
    content_layer = 'block5_conv2'
    style_layers = [
        'block1_conv1',
        'block2_conv1',
        'block3_conv1',
        'block4_conv1',
        'block5_conv1'
    ]

    total_variation_weight = 1e-4
    style_weight = 1.0
    content_weight = 0.025

    loss = K.variable(0.)
    layer_features = outputs_dict[content_layer]
    target_img_features = layer_features[0, :, :, :]
    combination_features = layer_features[2, :, :, :]
    loss += content_weight * content_loss(target_img_features, combination_features)

    for layer_name in style_layers:
        layer_features = outputs_dict[layer_name]
        style_features = layer_features[1, :, :, :]
        combination_features = layer_features[2, :, :, :]
        sl = style_loss(style_features, combination_features,
                        target_size=(gen_img_height, gen_img_width))
        loss += (style_weight / len(style_layers)) * sl

    loss += total_variation_weight * total_variation_loss(combination_img, target_size=(gen_img_height, gen_img_width))

    # setup gradient-descent
    grads_list = K.gradients(loss, combination_img)
    grads = grads_list[0]

    fetch_loss_and_grads = K.function(inputs=[combination_img],
                                      outputs=[loss, grads])

    lossAndGradsCache = LossAndGradsCache(fetch_loss_and_grads,
                                          target_size=(gen_img_height, gen_img_width))

    x = preprocess_img(FLAGS.target_img_path, target_size=(gen_img_height, gen_img_width))
    x = x.flatten()

    for i in range(FLAGS.iterations):
        start_time = time.time()

        x, min_val, info = fmin_l_bfgs_b(lossAndGradsCache.loss,
                                         x,
                                         fprime=lossAndGradsCache.grads,
                                         maxfun=20)
        print('@{:4d}: {:.4f}'.format(i + 1, min_val))

        x_copy = x.copy().reshape((gen_img_height, gen_img_width, 3))
        print(np.min(x_copy), np.mean(x_copy), np.max(x_copy))
        img = deprocess_img(x_copy)
        os.makedirs('out', exist_ok=True)
        filename = 'out/result_{:04d}.png'.format(i + 1)
        imsave(filename, img)
        print('Iteration took {:.1f}s'.format(time.time() - start_time))
コード例 #18
0
name = 'conv4_2'

name = 'conv5_3'
name = 'relu5_3'
name = 'relu3_3'
name = 'relu5_3'
name = 'conv1_1_D'
name = 'relu1_2_D'
name = 'relu4_3'
cvimg = cv2.resize(cv2.imread('car.png'), (input_shape[1], input_shape[0]))
nimage = cvimg
nimage = np.expand_dims(nimage, 0)
obj = 9

outputs = tf.argmax(logits, axis=3)
fn = K.function([inputs], [outputs])
mask = np.squeeze(np.asarray(fn([nimage])))
Image.fromarray(np.uint8(mask / 11. * 255)).save('recog.png')
mask[mask != obj] = 0
mask[mask == obj] = 1
Image.fromarray(np.uint8(mask / 11. * 255)).save('mask.png')
masks = np.zeros([1, input_shape[0], input_shape[1], 12])
masks[:, :, :, obj] = mask
signal = tf.multiply(logits, masks)
print logits
print masks.shape
loss = tf.reduce_mean(signal)
#loss = tf.reduce_sum((prob-masks)**2)
grads = tf.gradients(loss, end_points[name])[0]
# Normalizing the gradients
norm_grads = tf.div(
コード例 #19
0
    b = backend.square(x[:, :height - 1, :width - 1, :] -
                       x[:, :height - 1, 1:, :])
    return backend.sum(backend.pow(a + b, 1.25))


loss += total_variation_weight * total_variation_loss(combination_image)

# In[ ]:

grads = backend.gradients(loss, combination_image)

# In[ ]:

outputs = [loss]
outputs += grads
f_outputs = backend.function([combination_image], outputs)


def eval_loss_and_grads(x):
    x = x.reshape((1, height, width, 3))
    outs = f_outputs([x])
    loss_value = outs[0]
    grad_values = outs[1].flatten().astype('float64')
    return loss_value, grad_values


class Evaluator(object):
    def __init__(self):
        self.loss_value = None
        self.grads_values = None
コード例 #20
0
def main(_):
    # disable all training specific operations
    K.set_learning_phase(0)

    model = applications.inception_v3.InceptionV3(weights='imagenet',
                                                  include_top=False)
    layer_contributions = {
        'mixed2': 0.2,
        'mixed3': 3.0,
        'mixed4': 2.0,
        'mixed5': 1.5
    }

    layer_dict = dict([(layer.name, layer) for layer in model.layers])

    loss = K.variable(0.,)
    for layer_name in layer_contributions:
        coeff = layer_contributions[layer_name]
        activation = layer_dict[layer_name].output

        scaling = K.prod(K.cast(K.shape(activation), 'float32'))
        # avoid artifacts by only involving non-boarder pixels
        loss += coeff * K.sum(K.square(activation[:, 2:-2, 2:-2, :])) / scaling

    # start the gradient-ascent process
    dream = model.input

    grads_list = K.gradients(loss, dream)
    grads = grads_list[0]

    # trick: normalize gradients
    grads /= K.maximum(K.mean(K.abs(grads)), 1e-7)

    fetch_loss_and_grads = K.function(inputs=[dream],
                                      outputs=[loss, grads])

    def gradient_ascent(x, iterations, step_rate, max_loss=None):
        for i in range(iterations):
            loss_value, grads_value = fetch_loss_and_grads([x])
            if max_loss is not None and loss_value > max_loss:
                break
            print('@{:4d}: {:.4f}'.format(i, loss_value))
            x += step_rate * grads_value
        return x

    img = preprocess_img(FLAGS.img_path)

    original_shape = img.shape[1:3]
    successive_shapes = [original_shape]
    for i in range(1, NUM_OCTAVES):
        shape = tuple([int(dim / (OCTAVES_SCLAE ** i))
                      for dim in original_shape])
        successive_shapes.append(shape)

    # reverse
    successive_shapes = successive_shapes[::-1]

    original_img = np.copy(img)
    shrunk_original_img = resize_img(img, successive_shapes[0])

    for shape in successive_shapes:
        print('Preprocess image with shape: {}'.format(shape))
        img = resize_img(img, shape)
        img = gradient_ascent(img,
                              iterations=FLAGS.iterations,
                              step_rate=FLAGS.step_rate,
                              max_loss=MAX_LOSS)

        same_size_original = resize_img(original_img, shape)

        if FLAGS.repair_lost_detail:
            upscale_shrunk_original_img = resize_img(shrunk_original_img, shape)
            lost_detail = same_size_original - upscale_shrunk_original_img
            img += lost_detail

        shrunk_original_img = same_size_original
        save_img(img, filename='dream_at_scale_{}.png'.format(str(shape)))

    save_img(img, filename='dream.png')