Ejemplo n.º 1
0
    def test_build_fc_layers(self, is_training):
        batch_size = 5
        num_units_fc_layers = [128, 64, 32]
        images = _construct_images(batch_size)
        image_shape = tuple(images.get_shape().as_list()[1:])

        net_input = tf.layers.flatten(images)

        number_params = 0
        num_units_prev = np.prod(image_shape)
        for num_units in num_units_fc_layers:
            filter_size = (num_units_prev, num_units)
            # Add filter parameters count.
            number_params += np.prod(filter_size)
            output_size = num_units
            num_units_prev = num_units
            # Add batch norm mean and variance parameters count.
            number_params += num_units * 4

        final_shape = (batch_size, output_size)
        net, _ = model_utils.build_fc_layers(
            net_input,
            num_units_fc_layers=num_units_fc_layers,
            activation=tf.nn.relu,
            batch_norm=True,
            regularizer=tf.nn.l2_loss,
            is_training=is_training)

        vars_list = tf.global_variables()

        self.assertEqual(_count_parameters(vars_list), number_params)

        init = tf.global_variables_initializer()
        self.evaluate(init)
        self.assertEqual(final_shape, self.evaluate(net).shape)
    def __call__(self, input_state):
        """Builds classification network.

    Args:
      input_state: 2-D Tensor of shape [batch, state dimensionality]

    Returns:
      logits: Network logits.
      endpoints: Dictionary with activations at different layers.
    """
        if self.var_list:
            reuse = True
        else:
            reuse = False

        tf.logging.info("Builds Classification Network")
        endpoints = {}
        net = input_state

        # Fully connected layers.
        with tf.variable_scope("classification_network", reuse=reuse):
            net, endpoints_ = model_utils.build_fc_layers(
                net,
                self.num_units_fc_layers,
                activation=self.activation,
                regularizer=self.regularizer)
        endpoints.update(endpoints_)

        # Linear output layer.
        with tf.variable_scope("classification_network/output", reuse=reuse):
            logits, _ = model_utils.build_fc_layers(
                net, [self.num_classes],
                activation=None,
                regularizer=self.regularizer)
        endpoints["logits"] = logits

        if not reuse:
            self.collect_variables()
        return logits, endpoints
Ejemplo n.º 3
0
    def __call__(self,
                 input_state,
                 location_scale,
                 prev_locations=None,
                 is_training=False,
                 policy="learned",
                 sampling_stddev=1e-5):
        """Builds emission network.

    Args:
      input_state: 2-D Tensor of shape [batch, state dimensionality]
      location_scale: <= 1. and >= 0. the normalized location range
        [-location_scale, location_scale]
      prev_locations: if not None add prev_location to current proposed location
        (ie using relative locations)
      is_training: (Boolean) to indicate training or inference modes.
      policy: (String) 'learned': uses learned policy, 'random': uses random
        policy, or 'center': uses center look policy.
      sampling_stddev: Sampling distribution standard deviation.

    Returns:
      locations: network output reflecting next location to look at
        (normalized to range [-location_scale, location_scale]).
        The image locations mapping to locs are as follows:
          (-1, -1): upper left corner.
          (-1, 1): upper right corner.
          (1, 1): lower right corner.
          (1, -1): lower left corner.
      endpoints: dictionary with activations at different layers.
    """
        if self.var_list:
            reuse = True
        else:
            reuse = False

        batch_size = input_state.shape.as_list()[0]

        tf.logging.info("BUILD Emission Network")
        endpoints = {}
        net = input_state

        # Fully connected layers.
        with tf.variable_scope("emission_network", reuse=reuse):
            net, endpoints_ = model_utils.build_fc_layers(
                net,
                self.num_units_fc_layers,
                activation=self.activation,
                regularizer=self.regularizer)
        endpoints.update(endpoints_)

        # Tanh output layer.
        with tf.variable_scope("emission_network/output", reuse=reuse):
            output, _ = model_utils.build_fc_layers(
                net, [self.location_dims],
                activation=tf.nn.tanh,
                regularizer=self.regularizer)

        # scale location ([-location_scale, location_scale] range
        mean_locations = location_scale * output
        if prev_locations is not None:
            mean_locations = prev_locations + mean_locations

        if policy == "learned":
            endpoints["mean_locations"] = mean_locations
            if is_training:
                # At training samples random location.
                locations = mean_locations + tf.random_normal(
                    shape=(batch_size, self.location_dims),
                    stddev=sampling_stddev)
                # Ensures range [-location_scale, location_scale]
                locations = tf.clip_by_value(locations, -location_scale,
                                             location_scale)
                tf.logging.info("Sampling locations.")
                tf.logging.info(
                    "====================================================")
            else:
                # At inference uses the mean value for the location.
                locations = mean_locations

            locations = tf.stop_gradient(locations)
        elif policy == "random":
            # Use random policy for location.
            locations = tf.random_uniform(shape=(batch_size,
                                                 self.location_dims),
                                          minval=-location_scale,
                                          maxval=location_scale)
            endpoints["mean_locations"] = mean_locations
        elif policy == "center":
            # Use center look policy.
            locations = tf.zeros(shape=(batch_size, self.location_dims))
            endpoints["mean_locations"] = mean_locations
        else:
            raise ValueError(
                "policy can be either 'learned', 'random', or 'center'")

        if not reuse:
            self.collect_variables()
        return locations, endpoints