Ejemplo n.º 1
0
  def get_updates(self, loss, params):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * K.cast(self.iterations,
                                            K.dtype(self.decay))))

    t = K.cast(self.iterations, K.floatx()) + 1
    lr_t = lr * (K.sqrt(1. - K.pow(self.beta_2, t)) /
                 (1. - K.pow(self.beta_1, t)))

    ms = [K.zeros(K.int_shape(p), dtype=K.dtype(p)) for p in params]
    vs = [K.zeros(K.int_shape(p), dtype=K.dtype(p)) for p in params]
    self.weights = [self.iterations] + ms + vs

    for p, g, m, v in zip(params, grads, ms, vs):
      m_t = (self.beta_1 * m) + (1. - self.beta_1) * g
      v_t = (self.beta_2 * v) + (1. - self.beta_2) * K.square(g)
      p_t = p - lr_t * m_t / (K.sqrt(v_t) + self.epsilon)

      self.updates.append(K.update(m, m_t))
      self.updates.append(K.update(v, v_t))
      new_p = p_t

      # Apply constraints.
      if getattr(p, 'constraint', None) is not None:
        new_p = p.constraint(new_p)

      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 2
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  def get_updates(self, loss, params):
    grads = self.get_gradients(loss, params)
    accumulators = [
        K.zeros(K.int_shape(p), dtype=K.dtype(p)) for p in params
    ]
    self.weights = accumulators
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * K.cast(self.iterations,
                                            K.dtype(self.decay))))

    for p, g, a in zip(params, grads, accumulators):
      # update accumulator
      new_a = self.rho * a + (1. - self.rho) * K.square(g)
      self.updates.append(K.update(a, new_a))
      new_p = p - lr * g / (K.sqrt(new_a) + self.epsilon)

      # Apply constraints.
      if getattr(p, 'constraint', None) is not None:
        new_p = p.constraint(new_p)

      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 3
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  def get_updates(self, loss, params):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * K.cast(self.iterations,
                                            K.dtype(self.decay))))

    # momentum
    shapes = [K.int_shape(p) for p in params]
    moments = [K.zeros(shape) for shape in shapes]
    self.weights = [self.iterations] + moments
    for p, g, m in zip(params, grads, moments):
      v = self.momentum * m - lr * g  # velocity
      self.updates.append(K.update(m, v))

      if self.nesterov:
        new_p = p + self.momentum * v - lr * g
      else:
        new_p = p + v

      # Apply constraints.
      if getattr(p, 'constraint', None) is not None:
        new_p = p.constraint(new_p)

      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 4
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  def call(self, inputs, mask=None):
    input_shape = K.int_shape(inputs)
    if input_shape[0]:
      # batch size matters, use rnn-based implementation
      def step(x, _):
        output = self.layer.call(x)
        return output, []

      _, outputs, _ = K.rnn(
          step,
          inputs,
          initial_states=[],
          input_length=input_shape[1],
          unroll=False)
      y = outputs
    else:
      # No batch size specified, therefore the layer will be able
      # to process batches of any size.
      # We can go with reshape-based implementation for performance.
      input_length = input_shape[1]
      if not input_length:
        input_length = K.shape(inputs)[1]
      # Shape: (num_samples * timesteps, ...)
      inputs = K.reshape(inputs, (-1,) + input_shape[2:])
      y = self.layer.call(inputs)  # (num_samples * timesteps, ...)
      # Shape: (num_samples, timesteps, ...)
      output_shape = self._compute_output_shape(input_shape).as_list()  # pylint: disable=protected-access
      y = K.reshape(y, [-1, input_length] + output_shape[2:])

    # Apply activity regularizer if any:
    if (hasattr(self.layer, 'activity_regularizer') and
        self.layer.activity_regularizer is not None):
      regularization_loss = self.layer.activity_regularizer(y)
      self.add_loss(regularization_loss, inputs)
    return y
Ejemplo n.º 5
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    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        shapes = [K.int_shape(p) for p in params]
        accumulators = [K.zeros(shape) for shape in shapes]
        delta_accumulators = [K.zeros(shape) for shape in shapes]
        self.weights = accumulators + delta_accumulators
        self.updates = []

        lr = self.lr
        if self.initial_decay > 0:
            lr *= (1. / (1. + self.decay * self.iterations))
            self.updates.append(K.update_add(self.iterations, 1))

        for p, g, a, d_a in zip(params, grads, accumulators,
                                delta_accumulators):
            # update accumulator
            new_a = self.rho * a + (1. - self.rho) * K.square(g)
            self.updates.append(K.update(a, new_a))

            # use the new accumulator and the *old* delta_accumulator
            update = g * K.sqrt(d_a + self.epsilon) / K.sqrt(new_a +
                                                             self.epsilon)

            new_p = p - lr * update
            # apply constraints
            if p in constraints:
                c = constraints[p]
                new_p = c(new_p)
            self.updates.append(K.update(p, new_p))

            # update delta_accumulator
            new_d_a = self.rho * d_a + (1 - self.rho) * K.square(update)
            self.updates.append(K.update(d_a, new_d_a))
        return self.updates
Ejemplo n.º 6
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    shapes = [K.int_shape(p) for p in params]
    accumulators = [K.zeros(shape) for shape in shapes]
    delta_accumulators = [K.zeros(shape) for shape in shapes]
    self.weights = accumulators + delta_accumulators
    self.updates = []

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * self.iterations))
      self.updates.append(K.update_add(self.iterations, 1))

    for p, g, a, d_a in zip(params, grads, accumulators, delta_accumulators):
      # update accumulator
      new_a = self.rho * a + (1. - self.rho) * K.square(g)
      self.updates.append(K.update(a, new_a))

      # use the new accumulator and the *old* delta_accumulator
      update = g * K.sqrt(d_a + self.epsilon) / K.sqrt(new_a + self.epsilon)

      new_p = p - lr * update
      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)
      self.updates.append(K.update(p, new_p))

      # update delta_accumulator
      new_d_a = self.rho * d_a + (1 - self.rho) * K.square(update)
      self.updates.append(K.update(d_a, new_d_a))
    return self.updates
Ejemplo n.º 7
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * self.iterations))

    t = self.iterations + 1
    lr_t = lr * (K.sqrt(1. - K.pow(self.beta_2, t)) /
                 (1. - K.pow(self.beta_1, t)))

    shapes = [K.int_shape(p) for p in params]
    ms = [K.zeros(shape) for shape in shapes]
    vs = [K.zeros(shape) for shape in shapes]
    self.weights = [self.iterations] + ms + vs

    for p, g, m, v in zip(params, grads, ms, vs):
      m_t = (self.beta_1 * m) + (1. - self.beta_1) * g
      v_t = (self.beta_2 * v) + (1. - self.beta_2) * K.square(g)
      p_t = p - lr_t * m_t / (K.sqrt(v_t) + self.epsilon)

      self.updates.append(K.update(m, m_t))
      self.updates.append(K.update(v, v_t))

      new_p = p_t
      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)
      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 8
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    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        self.updates = [K.update_add(self.iterations, 1)]

        lr = self.lr
        if self.initial_decay > 0:
            lr *= (1. / (1. + self.decay * self.iterations))

        t = self.iterations + 1
        lr_t = lr * (K.sqrt(1. - K.pow(self.beta_2, t)) /
                     (1. - K.pow(self.beta_1, t)))

        shapes = [K.int_shape(p) for p in params]
        ms = [K.zeros(shape) for shape in shapes]
        vs = [K.zeros(shape) for shape in shapes]
        self.weights = [self.iterations] + ms + vs

        for p, g, m, v in zip(params, grads, ms, vs):
            m_t = (self.beta_1 * m) + (1. - self.beta_1) * g
            v_t = (self.beta_2 * v) + (1. - self.beta_2) * K.square(g)
            p_t = p - lr_t * m_t / (K.sqrt(v_t) + self.epsilon)

            self.updates.append(K.update(m, m_t))
            self.updates.append(K.update(v, v_t))

            new_p = p_t
            # apply constraints
            if p in constraints:
                c = constraints[p]
                new_p = c(new_p)
            self.updates.append(K.update(p, new_p))
        return self.updates
Ejemplo n.º 9
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    self.updates = []

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * self.iterations))
      self.updates.append(K.update_add(self.iterations, 1))

    # momentum
    shapes = [K.int_shape(p) for p in params]
    moments = [K.zeros(shape) for shape in shapes]
    self.weights = [self.iterations] + moments
    for p, g, m in zip(params, grads, moments):
      v = self.momentum * m - lr * g  # velocity
      self.updates.append(K.update(m, v))

      if self.nesterov:
        new_p = p + self.momentum * v - lr * g
      else:
        new_p = p + v

      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)

      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 10
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    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        self.updates = [K.update_add(self.iterations, 1)]

        lr = self.lr
        if self.initial_decay > 0:
            lr *= (1. / (1. + self.decay * self.iterations))

        t = self.iterations + 1
        lr_t = lr / (1. - K.pow(self.beta_1, t))

        shapes = [K.int_shape(p) for p in params]
        # zero init of 1st moment
        ms = [K.zeros(shape) for shape in shapes]
        # zero init of exponentially weighted infinity norm
        us = [K.zeros(shape) for shape in shapes]
        self.weights = [self.iterations] + ms + us

        for p, g, m, u in zip(params, grads, ms, us):

            m_t = (self.beta_1 * m) + (1. - self.beta_1) * g
            u_t = K.maximum(self.beta_2 * u, K.abs(g))
            p_t = p - lr_t * m_t / (u_t + self.epsilon)

            self.updates.append(K.update(m, m_t))
            self.updates.append(K.update(u, u_t))

            new_p = p_t
            # apply constraints
            if p in constraints:
                c = constraints[p]
                new_p = c(new_p)
            self.updates.append(K.update(p, new_p))
        return self.updates
Ejemplo n.º 11
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  def get_updates(self, loss, params):
    grads = self.get_gradients(loss, params)
    shapes = [K.int_shape(p) for p in params]
    accumulators = [K.zeros(shape) for shape in shapes]
    delta_accumulators = [K.zeros(shape) for shape in shapes]
    self.weights = accumulators + delta_accumulators
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * K.cast(self.iterations,
                                            K.dtype(self.decay))))

    for p, g, a, d_a in zip(params, grads, accumulators, delta_accumulators):
      # update accumulator
      new_a = self.rho * a + (1. - self.rho) * K.square(g)
      self.updates.append(K.update(a, new_a))

      # use the new accumulator and the *old* delta_accumulator
      update = g * K.sqrt(d_a + self.epsilon) / K.sqrt(new_a + self.epsilon)
      new_p = p - lr * update

      # Apply constraints.
      if getattr(p, 'constraint', None) is not None:
        new_p = p.constraint(new_p)

      self.updates.append(K.update(p, new_p))

      # update delta_accumulator
      new_d_a = self.rho * d_a + (1 - self.rho) * K.square(update)
      self.updates.append(K.update(d_a, new_d_a))
    return self.updates
Ejemplo n.º 12
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    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        self.updates = []

        lr = self.lr
        if self.initial_decay > 0:
            lr *= (1. / (1. + self.decay * self.iterations))
            self.updates.append(K.update_add(self.iterations, 1))

        # momentum
        shapes = [K.int_shape(p) for p in params]
        moments = [K.zeros(shape) for shape in shapes]
        self.weights = [self.iterations] + moments
        for p, g, m in zip(params, grads, moments):
            v = self.momentum * m - lr * g  # velocity
            self.updates.append(K.update(m, v))

            if self.nesterov:
                new_p = p + self.momentum * v - lr * g
            else:
                new_p = p + v

            # apply constraints
            if p in constraints:
                c = constraints[p]
                new_p = c(new_p)

            self.updates.append(K.update(p, new_p))
        return self.updates
Ejemplo n.º 13
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  def get_constants(self, inputs, training=None):
    constants = []
    if self.implementation != 0 and 0 < self.dropout < 1:
      input_shape = K.int_shape(inputs)
      input_dim = input_shape[-1]
      ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
      ones = K.tile(ones, (1, int(input_dim)))

      def dropped_inputs():
        return K.dropout(ones, self.dropout)

      dp_mask = [
          K.in_train_phase(dropped_inputs, ones, training=training)
          for _ in range(3)
      ]
      constants.append(dp_mask)
    else:
      constants.append([K.cast_to_floatx(1.) for _ in range(3)])

    if 0 < self.recurrent_dropout < 1:
      ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
      ones = K.tile(ones, (1, self.units))

      def dropped_inputs():  # pylint: disable=function-redefined
        return K.dropout(ones, self.recurrent_dropout)

      rec_dp_mask = [
          K.in_train_phase(dropped_inputs, ones, training=training)
          for _ in range(3)
      ]
      constants.append(rec_dp_mask)
    else:
      constants.append([K.cast_to_floatx(1.) for _ in range(3)])
    return constants
Ejemplo n.º 14
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  def get_constants(self, inputs, training=None):
    constants = []
    if self.implementation != 0 and 0 < self.dropout < 1:
      input_shape = K.int_shape(inputs)
      input_dim = input_shape[-1]
      ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
      ones = K.tile(ones, (1, int(input_dim)))

      def dropped_inputs():
        return K.dropout(ones, self.dropout)

      dp_mask = [
          K.in_train_phase(dropped_inputs, ones, training=training)
          for _ in range(3)
      ]
      constants.append(dp_mask)
    else:
      constants.append([K.cast_to_floatx(1.) for _ in range(3)])

    if 0 < self.recurrent_dropout < 1:
      ones = K.ones_like(K.reshape(inputs[:, 0, 0], (-1, 1)))
      ones = K.tile(ones, (1, self.units))

      def dropped_inputs():  # pylint: disable=function-redefined
        return K.dropout(ones, self.recurrent_dropout)

      rec_dp_mask = [
          K.in_train_phase(dropped_inputs, ones, training=training)
          for _ in range(3)
      ]
      constants.append(rec_dp_mask)
    else:
      constants.append([K.cast_to_floatx(1.) for _ in range(3)])
    return constants
Ejemplo n.º 15
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  def get_updates(self, loss, params):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * K.cast(self.iterations,
                                            K.dtype(self.decay))))

    t = K.cast(self.iterations, K.floatx()) + 1
    lr_t = lr / (1. - K.pow(self.beta_1, t))

    shapes = [K.int_shape(p) for p in params]
    # zero init of 1st moment
    ms = [K.zeros(shape) for shape in shapes]
    # zero init of exponentially weighted infinity norm
    us = [K.zeros(shape) for shape in shapes]
    self.weights = [self.iterations] + ms + us

    for p, g, m, u in zip(params, grads, ms, us):

      m_t = (self.beta_1 * m) + (1. - self.beta_1) * g
      u_t = K.maximum(self.beta_2 * u, K.abs(g))
      p_t = p - lr_t * m_t / (u_t + self.epsilon)

      self.updates.append(K.update(m, m_t))
      self.updates.append(K.update(u, u_t))
      new_p = p_t

      # Apply constraints.
      if getattr(p, 'constraint', None) is not None:
        new_p = p.constraint(new_p)

      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 16
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  def call(self, inputs, mask=None):
    input_shape = K.int_shape(inputs)
    if input_shape[0]:
      # batch size matters, use rnn-based implementation
      def step(x, _):
        output = self.layer.call(x)
        return output, []

      _, outputs, _ = K.rnn(
          step,
          inputs,
          initial_states=[],
          input_length=input_shape[1],
          unroll=False)
      y = outputs
    else:
      # No batch size specified, therefore the layer will be able
      # to process batches of any size.
      # We can go with reshape-based implementation for performance.
      input_length = input_shape[1]
      if not input_length:
        input_length = K.shape(inputs)[1]
      # Shape: (num_samples * timesteps, ...)
      inputs = K.reshape(inputs, (-1,) + input_shape[2:])
      y = self.layer.call(inputs)  # (num_samples * timesteps, ...)
      # Shape: (num_samples, timesteps, ...)
      output_shape = self._compute_output_shape(input_shape).as_list()  # pylint: disable=protected-access
      y = K.reshape(y, [-1, input_length] + output_shape[2:])

    # Apply activity regularizer if any:
    if (hasattr(self.layer, 'activity_regularizer') and
        self.layer.activity_regularizer is not None):
      regularization_loss = self.layer.activity_regularizer(y)
      self.add_loss(regularization_loss, inputs)
    return y
Ejemplo n.º 17
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  def call(self, inputs, mask=None, initial_state=None, training=None):
    # input shape: `(samples, time (padded with zeros), input_dim)`
    # note that the .build() method of subclasses MUST define
    # self.input_spec and self.state_spec with complete input shapes.
    if initial_state is not None:
      if not isinstance(initial_state, (list, tuple)):
        initial_states = [initial_state]
      else:
        initial_states = list(initial_state)
    if isinstance(inputs, list):
      initial_states = inputs[1:]
      inputs = inputs[0]
    elif self.stateful:
      initial_states = self.states
    else:
      initial_states = self.get_initial_states(inputs)

    if len(initial_states) != len(self.states):
      raise ValueError('Layer has ' + str(len(self.states)) +
                       ' states but was passed ' + str(len(initial_states)) +
                       ' initial states.')
    input_shape = K.int_shape(inputs)
    if self.unroll and input_shape[1] is None:
      raise ValueError('Cannot unroll a RNN if the '
                       'time dimension is undefined. \n'
                       '- If using a Sequential model, '
                       'specify the time dimension by passing '
                       'an `input_shape` or `batch_input_shape` '
                       'argument to your first layer. If your '
                       'first layer is an Embedding, you can '
                       'also use the `input_length` argument.\n'
                       '- If using the functional API, specify '
                       'the time dimension by passing a `shape` '
                       'or `batch_shape` argument to your Input layer.')
    constants = self.get_constants(inputs, training=None)
    preprocessed_input = self.preprocess_input(inputs, training=None)
    last_output, outputs, states = K.rnn(
        self.step,
        preprocessed_input,
        initial_states,
        go_backwards=self.go_backwards,
        mask=mask,
        constants=constants,
        unroll=self.unroll)
    if self.stateful:
      updates = []
      for i in range(len(states)):
        updates.append((self.states[i], states[i]))
      self.add_update(updates, inputs)

    # Properly set learning phase
    if 0 < self.dropout + self.recurrent_dropout:
      last_output._uses_learning_phase = True
      outputs._uses_learning_phase = True

    if self.return_sequences:
      return outputs
    else:
      return last_output
Ejemplo n.º 18
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 def call(self, x, mask=None):
     input_shape = K.int_shape(x)
     layer_width = input_shape[self.waxis]
     layer_height = input_shape[self.haxis]
     img_width = self.img_size[0]
     img_height = self.img_size[1]
     # define prior boxes shapes
     box_widths = []
     box_heights = []
     for ar in self.aspect_ratios:
         if ar == 1 and len(box_widths) == 0:
             box_widths.append(self.min_size)
             box_heights.append(self.min_size)
         elif ar == 1 and len(box_widths) > 0:
             box_widths.append(np.sqrt(self.min_size * self.max_size))
             box_heights.append(np.sqrt(self.min_size * self.max_size))
         elif ar != 1:
             box_widths.append(self.min_size * np.sqrt(ar))
             box_heights.append(self.min_size / np.sqrt(ar))
     box_widths = 0.5 * np.array(box_widths)
     box_heights = 0.5 * np.array(box_heights)
     # define centers of prior boxes
     step_x = img_width / layer_width
     step_y = img_height / layer_height
     linx = np.linspace(0.5 * step_x, img_width - 0.5 * step_x, layer_width)
     liny = np.linspace(0.5 * step_y, img_height - 0.5 * step_y,
                        layer_height)
     centers_x, centers_y = np.meshgrid(linx, liny)
     centers_x = centers_x.reshape(-1, 1)
     centers_y = centers_y.reshape(-1, 1)
     # define xmin, ymin, xmax, ymax of prior boxes
     num_priors_ = len(self.aspect_ratios)
     prior_boxes = np.concatenate((centers_x, centers_y), axis=1)
     prior_boxes = np.tile(prior_boxes, (1, 2 * num_priors_))
     prior_boxes[:, ::4] -= box_widths
     prior_boxes[:, 1::4] -= box_heights
     prior_boxes[:, 2::4] += box_widths
     prior_boxes[:, 3::4] += box_heights
     prior_boxes[:, ::2] /= img_width
     prior_boxes[:, 1::2] /= img_height
     prior_boxes = prior_boxes.reshape(-1, 4)
     if self.clip:
         prior_boxes = np.minimum(np.maximum(prior_boxes, 0.0), 1.0)
     # define variances
     num_boxes = len(prior_boxes)
     if len(self.variances) == 1:
         variances = np.ones((num_boxes, 4)) * self.variances[0]
     elif len(self.variances) == 4:
         variances = np.tile(self.variances, (num_boxes, 1))
     else:
         raise Exception('Must provide one or four variances.')
     prior_boxes = np.concatenate((prior_boxes, variances), axis=1)
     prior_boxes_tensor = K.expand_dims(K.variable(prior_boxes), 0)
     pattern = [tf.shape(x)[0], 1, 1]
     prior_boxes_tensor = tf.tile(prior_boxes_tensor, pattern)
     return prior_boxes_tensor
def resize_images_bilinear(x, height_factor, width_factor, data_format):
    """Resizes the images contained in a 4D tensor.
  Arguments:
      x: Tensor or variable to resize.
      height_factor: Positive integer.
      width_factor: Positive integer.
      data_format: One of `"channels_first"`, `"channels_last"`.
  Returns:
      A tensor.
  Raises:
      ValueError: if `data_format` is neither
          `channels_last` or `channels_first`.
  """
    if data_format == 'channels_first':
        original_shape = K.int_shape(x)
        new_shape = array_ops.shape(x)[2:]
        new_shape *= constant_op.constant(
            np.array([height_factor, width_factor]).astype('int32'))
        x = permute_dimensions(x, [0, 2, 3, 1])
        x = image_ops.resize_bilinear(x, new_shape)
        x = permute_dimensions(x, [0, 3, 1, 2])
        x.set_shape((None, None, original_shape[2] *
                     height_factor if original_shape[2] is not None else None,
                     original_shape[3] *
                     width_factor if original_shape[3] is not None else None))
        return x
    elif data_format == 'channels_last':
        original_shape = K.int_shape(x)
        new_shape = array_ops.shape(x)[1:3]
        new_shape *= constant_op.constant(
            np.array([height_factor, width_factor]).astype('int32'))
        x = image_ops.resize_bilinear(x, new_shape)
        x.set_shape(
            (None, original_shape[1] *
             height_factor if original_shape[1] is not None else None,
             original_shape[2] *
             width_factor if original_shape[2] is not None else None, None))
        return x
    else:
        raise ValueError('Invalid data_format:', data_format)
Ejemplo n.º 20
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  def call(self, inputs, training=None, mask=None):
    kwargs = {}
    if has_arg(self.layer.call, 'training'):
      kwargs['training'] = training
    uses_learning_phase = False  # pylint: disable=redefined-outer-name

    input_shape = K.int_shape(inputs)
    if input_shape[0]:
      # batch size matters, use rnn-based implementation
      def step(x, _):
        global uses_learning_phase  # pylint: disable=global-variable-undefined
        output = self.layer.call(x, **kwargs)
        if hasattr(output, '_uses_learning_phase'):
          uses_learning_phase = (output._uses_learning_phase or
                                 uses_learning_phase)
        return output, []

      _, outputs, _ = K.rnn(
          step,
          inputs,
          initial_states=[],
          unroll=False)
      y = outputs
    else:
      # No batch size specified, therefore the layer will be able
      # to process batches of any size.
      # We can go with reshape-based implementation for performance.
      input_length = input_shape[1]
      if not input_length:
        input_length = K.shape(inputs)[1]
      # Shape: (num_samples * timesteps, ...). And track the
      # transformation in self._input_map.
      input_uid = tf_base_layers._object_list_uid(inputs)
      inputs = K.reshape(inputs, (-1,) + input_shape[2:])
      self._input_map[input_uid] = inputs
      # (num_samples * timesteps, ...)
      y = self.layer.call(inputs, **kwargs)
      if hasattr(y, '_uses_learning_phase'):
        uses_learning_phase = y._uses_learning_phase
      # Shape: (num_samples, timesteps, ...)
      output_shape = self._compute_output_shape(input_shape).as_list()
      y = K.reshape(y, (-1, input_length) + tuple(output_shape[2:]))

    # Apply activity regularizer if any:
    if (hasattr(self.layer, 'activity_regularizer') and
        self.layer.activity_regularizer is not None):
      regularization_loss = self.layer.activity_regularizer(y)
      self.add_loss(regularization_loss, inputs)

    if uses_learning_phase:
      y._uses_learning_phase = True
    return y
Ejemplo n.º 21
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    def call(self, inputs, training=None, mask=None):
        kwargs = {}
        if has_arg(self.layer.call, 'training'):
            kwargs['training'] = training
        uses_learning_phase = False  # pylint: disable=redefined-outer-name

        input_shape = K.int_shape(inputs)
        if input_shape[0]:
            # batch size matters, use rnn-based implementation
            def step(x, _):
                global uses_learning_phase  # pylint: disable=global-variable-undefined
                output = self.layer.call(x, **kwargs)
                if hasattr(output, '_uses_learning_phase'):
                    uses_learning_phase = (output._uses_learning_phase
                                           or uses_learning_phase)
                return output, []

            _, outputs, _ = K.rnn(step,
                                  inputs,
                                  initial_states=[],
                                  unroll=False)
            y = outputs
        else:
            # No batch size specified, therefore the layer will be able
            # to process batches of any size.
            # We can go with reshape-based implementation for performance.
            input_length = input_shape[1]
            if not input_length:
                input_length = K.shape(inputs)[1]
            # Shape: (num_samples * timesteps, ...). And track the
            # transformation in self._input_map.
            input_uid = tf_base_layers._object_list_uid(inputs)
            inputs = K.reshape(inputs, (-1, ) + input_shape[2:])
            self._input_map[input_uid] = inputs
            # (num_samples * timesteps, ...)
            y = self.layer.call(inputs, **kwargs)
            if hasattr(y, '_uses_learning_phase'):
                uses_learning_phase = y._uses_learning_phase
            # Shape: (num_samples, timesteps, ...)
            output_shape = self._compute_output_shape(input_shape).as_list()
            y = K.reshape(y, (-1, input_length) + tuple(output_shape[2:]))

        # Apply activity regularizer if any:
        if (hasattr(self.layer, 'activity_regularizer')
                and self.layer.activity_regularizer is not None):
            regularization_loss = self.layer.activity_regularizer(y)
            self.add_loss(regularization_loss, inputs)

        if uses_learning_phase:
            y._uses_learning_phase = True
        return y
Ejemplo n.º 22
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    t = self.iterations + 1

    # Due to the recommendations in [2], i.e. warming momentum schedule
    momentum_cache_t = self.beta_1 * (1. - 0.5 *
                                      (K.pow(0.96, t * self.schedule_decay)))
    momentum_cache_t_1 = self.beta_1 * (1. - 0.5 *
                                        (K.pow(0.96,
                                               (t + 1) * self.schedule_decay)))
    m_schedule_new = self.m_schedule * momentum_cache_t
    m_schedule_next = self.m_schedule * momentum_cache_t * momentum_cache_t_1
    self.updates.append((self.m_schedule, m_schedule_new))

    shapes = [K.int_shape(p) for p in params]
    ms = [K.zeros(shape) for shape in shapes]
    vs = [K.zeros(shape) for shape in shapes]

    self.weights = [self.iterations] + ms + vs

    for p, g, m, v in zip(params, grads, ms, vs):
      # the following equations given in [1]
      g_prime = g / (1. - m_schedule_new)
      m_t = self.beta_1 * m + (1. - self.beta_1) * g
      m_t_prime = m_t / (1. - m_schedule_next)
      v_t = self.beta_2 * v + (1. - self.beta_2) * K.square(g)
      v_t_prime = v_t / (1. - K.pow(self.beta_2, t))
      m_t_bar = (
          1. - momentum_cache_t) * g_prime + momentum_cache_t_1 * m_t_prime

      self.updates.append(K.update(m, m_t))
      self.updates.append(K.update(v, v_t))

      p_t = p - self.lr * m_t_bar / (K.sqrt(v_t_prime) + self.epsilon)
      new_p = p_t

      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)
      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 23
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    self.updates = [K.update_add(self.iterations, 1)]

    t = self.iterations + 1

    # Due to the recommendations in [2], i.e. warming momentum schedule
    momentum_cache_t = self.beta_1 * (1. - 0.5 *
                                      (K.pow(0.96, t * self.schedule_decay)))
    momentum_cache_t_1 = self.beta_1 * (1. - 0.5 *
                                        (K.pow(0.96,
                                               (t + 1) * self.schedule_decay)))
    m_schedule_new = self.m_schedule * momentum_cache_t
    m_schedule_next = self.m_schedule * momentum_cache_t * momentum_cache_t_1
    self.updates.append((self.m_schedule, m_schedule_new))

    shapes = [K.int_shape(p) for p in params]
    ms = [K.zeros(shape) for shape in shapes]
    vs = [K.zeros(shape) for shape in shapes]

    self.weights = [self.iterations] + ms + vs

    for p, g, m, v in zip(params, grads, ms, vs):
      # the following equations given in [1]
      g_prime = g / (1. - m_schedule_new)
      m_t = self.beta_1 * m + (1. - self.beta_1) * g
      m_t_prime = m_t / (1. - m_schedule_next)
      v_t = self.beta_2 * v + (1. - self.beta_2) * K.square(g)
      v_t_prime = v_t / (1. - K.pow(self.beta_2, t))
      m_t_bar = (
          1. - momentum_cache_t) * g_prime + momentum_cache_t_1 * m_t_prime

      self.updates.append(K.update(m, m_t))
      self.updates.append(K.update(v, v_t))

      p_t = p - self.lr * m_t_bar / (K.sqrt(v_t_prime) + self.epsilon)
      new_p = p_t

      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)
      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 24
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  def pop(self):
    """Removes the last layer in the model.

    Raises:
        TypeError: if there are no layers in the model.
    """
    if not self.layers:
      raise TypeError('There are no layers in the model.')

    self.layers.pop()
    if not self.layers:
      self.outputs = []
      self.inbound_nodes = []
      self.outbound_nodes = []
    else:
      self.layers[-1].outbound_nodes = []
      self.outputs = [self.layers[-1].output]
      # update self.inbound_nodes
      self.inbound_nodes[0].output_tensors = self.outputs
      self.inbound_nodes[0].output_shapes = [K.int_shape(self.outputs[0])]
    self.built = False
Ejemplo n.º 25
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  def pop(self):
    """Removes the last layer in the model.

    Raises:
        TypeError: if there are no layers in the model.
    """
    if not self.layers:
      raise TypeError('There are no layers in the model.')

    self.layers.pop()
    if not self.layers:
      self.outputs = []
      self.inbound_nodes = []
      self.outbound_nodes = []
    else:
      self.layers[-1].outbound_nodes = []
      self.outputs = [self.layers[-1].output]
      # update self.inbound_nodes
      self.inbound_nodes[0].output_tensors = self.outputs
      self.inbound_nodes[0].output_shapes = [K.int_shape(self.outputs[0])]
    self.built = False
Ejemplo n.º 26
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  def get_updates(self, params, constraints, loss):
    grads = self.get_gradients(loss, params)
    shapes = [K.int_shape(p) for p in params]
    accumulators = [K.zeros(shape) for shape in shapes]
    self.weights = accumulators
    self.updates = []

    lr = self.lr
    if self.initial_decay > 0:
      lr *= (1. / (1. + self.decay * self.iterations))
      self.updates.append(K.update_add(self.iterations, 1))

    for p, g, a in zip(params, grads, accumulators):
      new_a = a + K.square(g)  # update accumulator
      self.updates.append(K.update(a, new_a))
      new_p = p - lr * g / (K.sqrt(new_a) + self.epsilon)
      # apply constraints
      if p in constraints:
        c = constraints[p]
        new_p = c(new_p)
      self.updates.append(K.update(p, new_p))
    return self.updates
Ejemplo n.º 27
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    def get_updates(self, params, constraints, loss):
        grads = self.get_gradients(loss, params)
        shapes = [K.int_shape(p) for p in params]
        accumulators = [K.zeros(shape) for shape in shapes]
        self.weights = accumulators
        self.updates = []

        lr = self.lr
        if self.initial_decay > 0:
            lr *= (1. / (1. + self.decay * self.iterations))
            self.updates.append(K.update_add(self.iterations, 1))

        for p, g, a in zip(params, grads, accumulators):
            new_a = a + K.square(g)  # update accumulator
            self.updates.append(K.update(a, new_a))
            new_p = p - lr * g / (K.sqrt(new_a) + self.epsilon)
            # apply constraints
            if p in constraints:
                c = constraints[p]
                new_p = c(new_p)
            self.updates.append(K.update(p, new_p))
        return self.updates
Ejemplo n.º 28
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def inception_resnet_block(x, scale, block_type, block_idx, activation='relu'):
    """Adds a Inception-ResNet block.
    This function builds 3 types of Inception-ResNet blocks mentioned
    in the paper, controlled by the `block_type` argument (which is the
    block name used in the official TF-slim implementation):
        - Inception-ResNet-A: `block_type='block35'`
        - Inception-ResNet-B: `block_type='block17'`
        - Inception-ResNet-C: `block_type='block8'`
    # Arguments
        x: input tensor.
        scale: scaling factor to scale the residuals (i.e., the output of
            passing `x` through an inception module) before adding them
            to the shortcut branch. Let `r` be the output from the residual branch,
            the output of this block will be `x + scale * r`.
        block_type: `'block35'`, `'block17'` or `'block8'`, determines
            the network structure in the residual branch.
        block_idx: an `int` used for generating layer names. The Inception-ResNet blocks
            are repeated many times in this network. We use `block_idx` to identify
            each of the repetitions. For example, the first Inception-ResNet-A block
            will have `block_type='block35', block_idx=0`, ane the layer names will have
            a common prefix `'block35_0'`.
        activation: activation function to use at the end of the block
            (see [activations](../activations.md)).
            When `activation=None`, no activation is applied
            (i.e., "linear" activation: `a(x) = x`).
    # Returns
        Output tensor for the block.
    # Raises
        ValueError: if `block_type` is not one of `'block35'`,
            `'block17'` or `'block8'`.
    """
    if block_type == 'block35':
        branch_0 = conv2d_bn(x, 32, 1)
        branch_1 = conv2d_bn(x, 32, 1)
        branch_1 = conv2d_bn(branch_1, 32, 3)
        branch_2 = conv2d_bn(x, 32, 1)
        branch_2 = conv2d_bn(branch_2, 48, 3)
        branch_2 = conv2d_bn(branch_2, 64, 3)
        branches = [branch_0, branch_1, branch_2]
    elif block_type == 'block17':
        branch_0 = conv2d_bn(x, 192, 1)
        branch_1 = conv2d_bn(x, 128, 1)
        branch_1 = conv2d_bn(branch_1, 160, [1, 7])
        branch_1 = conv2d_bn(branch_1, 192, [7, 1])
        branches = [branch_0, branch_1]
    elif block_type == 'block8':
        branch_0 = conv2d_bn(x, 192, 1)
        branch_1 = conv2d_bn(x, 192, 1)
        branch_1 = conv2d_bn(branch_1, 224, [1, 3])
        branch_1 = conv2d_bn(branch_1, 256, [3, 1])
        branches = [branch_0, branch_1]
    else:
        raise ValueError('Unknown Inception-ResNet block type. '
                         'Expects "block35", "block17" or "block8", '
                         'but got: ' + str(block_type))

    block_name = block_type + '_' + str(block_idx)
    channel_axis = 1 if K.image_data_format() == 'channels_first' else 3
    mixed = Concatenate(axis=channel_axis,
                        name=block_name + '_mixed')(branches)
    up = conv2d_bn(mixed,
                   K.int_shape(x)[channel_axis],
                   1,
                   activation=None,
                   use_bias=True,
                   name=block_name + '_conv')

    x = Lambda(lambda inputs, scale: inputs[0] + inputs[1] * scale,
               output_shape=K.int_shape(x)[1:],
               arguments={'scale': scale},
               name=block_name)([x, up])
    if activation is not None:
        x = Activation(activation, name=block_name + '_ac')(x)
    return x
Ejemplo n.º 29
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  def set_model(self, model):
    self.model = model
    self.sess = K.get_session()
    if self.histogram_freq and self.merged is None:
      for layer in self.model.layers:
        for weight in layer.weights:
          mapped_weight_name = weight.name.replace(':', '_')
          tf_summary.histogram(mapped_weight_name, weight)
          if self.write_grads:
            grads = model.optimizer.get_gradients(model.total_loss, weight)
            tf_summary.histogram('{}_grad'.format(mapped_weight_name), grads)
          if self.write_images:
            w_img = array_ops.squeeze(weight)
            shape = K.int_shape(w_img)
            if len(shape) == 2:  # dense layer kernel case
              if shape[0] > shape[1]:
                w_img = array_ops.transpose(w_img)
                shape = K.int_shape(w_img)
              w_img = array_ops.reshape(w_img, [1, shape[0], shape[1], 1])
            elif len(shape) == 3:  # convnet case
              if K.image_data_format() == 'channels_last':
                # switch to channels_first to display
                # every kernel as a separate image
                w_img = array_ops.transpose(w_img, perm=[2, 0, 1])
                shape = K.int_shape(w_img)
              w_img = array_ops.reshape(w_img,
                                        [shape[0], shape[1], shape[2], 1])
            elif len(shape) == 1:  # bias case
              w_img = array_ops.reshape(w_img, [1, shape[0], 1, 1])
            else:
              # not possible to handle 3D convnets etc.
              continue

            shape = K.int_shape(w_img)
            assert len(shape) == 4 and shape[-1] in [1, 3, 4]
            tf_summary.image(mapped_weight_name, w_img)

        if hasattr(layer, 'output'):
          tf_summary.histogram('{}_out'.format(layer.name), layer.output)
    self.merged = tf_summary.merge_all()

    if self.write_graph:
      self.writer = tf_summary.FileWriter(self.log_dir, self.sess.graph)
    else:
      self.writer = tf_summary.FileWriter(self.log_dir)

    if self.embeddings_freq:
      embeddings_layer_names = self.embeddings_layer_names

      if not embeddings_layer_names:
        embeddings_layer_names = [
            layer.name for layer in self.model.layers
            if type(layer).__name__ == 'Embedding'
        ]

      embeddings = {
          layer.name: layer.weights[0]
          for layer in self.model.layers if layer.name in embeddings_layer_names
      }

      self.saver = saver_lib.Saver(list(embeddings.values()))

      embeddings_metadata = {}

      if not isinstance(self.embeddings_metadata, str):
        embeddings_metadata = self.embeddings_metadata
      else:
        embeddings_metadata = {
            layer_name: self.embeddings_metadata
            for layer_name in embeddings.keys()
        }

      config = projector.ProjectorConfig()
      self.embeddings_ckpt_path = os.path.join(self.log_dir,
                                               'keras_embedding.ckpt')

      for layer_name, tensor in embeddings.items():
        embedding = config.embeddings.add()
        embedding.tensor_name = tensor.name

        if layer_name in embeddings_metadata:
          embedding.metadata_path = embeddings_metadata[layer_name]

      projector.visualize_embeddings(self.writer, config)
Ejemplo n.º 30
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    def add(self, layer):
        """Adds a layer instance on top of the layer stack.

    Arguments:
        layer: layer instance.

    Raises:
        TypeError: If `layer` is not a layer instance.
        ValueError: In case the `layer` argument does not
            know its input shape.
        ValueError: In case the `layer` argument has
            multiple output tensors, or is already connected
            somewhere else (forbidden in `Sequential` models).
    """
        if not isinstance(layer, Layer):
            raise TypeError('The added layer must be '
                            'an instance of class Layer. '
                            'Found: ' + str(layer))
        if not self.outputs:
            # first layer in model: check that it is an input layer
            if not layer.inbound_nodes:
                # create an input layer
                if not hasattr(layer, 'batch_input_shape'):
                    raise ValueError('The first layer in a '
                                     'Sequential model must '
                                     'get an `input_shape` or '
                                     '`batch_input_shape` argument.')
                # Instantiate the input layer.
                x = Input(batch_shape=layer.batch_input_shape,
                          dtype=layer.dtype,
                          name=layer.name + '_input')
                # This will build the current layer
                # and create the node connecting the current layer
                # to the input layer we just created.
                layer(x)

            if len(layer.inbound_nodes) != 1:
                raise ValueError('A layer added to a Sequential model must '
                                 'not already be connected somewhere else. '
                                 'Model received layer ' + layer.name +
                                 ' which has ' +
                                 str(len(layer.inbound_nodes)) +
                                 ' pre-existing inbound connections.')

            if len(layer.inbound_nodes[0].output_tensors) != 1:
                raise ValueError('All layers in a Sequential model '
                                 'should have a single output tensor. '
                                 'For multi-output layers, '
                                 'use the functional API.')

            self.outputs = [layer.inbound_nodes[0].output_tensors[0]]
            self.inputs = topology.get_source_inputs(self.outputs[0])

            # We create an input node, which we will keep updated
            # as we add more layers
            topology.Node(
                outbound_layer=self,
                inbound_layers=[],
                node_indices=[],
                tensor_indices=[],
                input_tensors=self.inputs,
                output_tensors=self.outputs,
                # no model-level masking for now
                input_masks=[None for _ in self.inputs],
                output_masks=[None])
        else:
            output_tensor = layer(self.outputs[0])
            if isinstance(output_tensor, list):
                raise TypeError('All layers in a Sequential model '
                                'should have a single output tensor. '
                                'For multi-output layers, '
                                'use the functional API.')
            self.outputs = [output_tensor]
            # update self.inbound_nodes
            self.inbound_nodes[0].output_tensors = self.outputs
            self.inbound_nodes[0].output_shapes = [
                K.int_shape(self.outputs[0])
            ]

        self.layers.append(layer)
        self.built = False
Ejemplo n.º 31
0
  def call(self, inputs, mask=None, training=None, initial_state=None):
    # input shape: `(samples, time (padded with zeros), input_dim)`
    # note that the .build() method of subclasses MUST define
    # self.input_spec and self.state_spec with complete input shapes.
    if isinstance(inputs, list):
      initial_state = inputs[1:]
      inputs = inputs[0]
    elif initial_state is not None:
      pass
    elif self.stateful:
      initial_state = self.states
    else:
      initial_state = self.get_initial_state(inputs)

    if isinstance(mask, list):
      mask = mask[0]

    if len(initial_state) != len(self.states):
      raise ValueError('Layer has ' + str(len(self.states)) +
                       ' states but was passed ' + str(len(initial_state)) +
                       ' initial states.')
    input_shape = K.int_shape(inputs)
    if self.unroll and input_shape[1] is None:
      raise ValueError('Cannot unroll a RNN if the '
                       'time dimension is undefined. \n'
                       '- If using a Sequential model, '
                       'specify the time dimension by passing '
                       'an `input_shape` or `batch_input_shape` '
                       'argument to your first layer. If your '
                       'first layer is an Embedding, you can '
                       'also use the `input_length` argument.\n'
                       '- If using the functional API, specify '
                       'the time dimension by passing a `shape` '
                       'or `batch_shape` argument to your Input layer.')
    constants = self.get_constants(inputs, training=None)
    preprocessed_input = self.preprocess_input(inputs, training=None)
    last_output, outputs, states = K.rnn(
        self.step,
        preprocessed_input,
        initial_state,
        go_backwards=self.go_backwards,
        mask=mask,
        constants=constants,
        unroll=self.unroll)
    if self.stateful:
      updates = []
      for i in range(len(states)):
        updates.append((self.states[i], states[i]))
      self.add_update(updates, inputs)

    # Properly set learning phase
    if 0 < self.dropout + self.recurrent_dropout:
      last_output._uses_learning_phase = True
      outputs._uses_learning_phase = True

    if not self.return_sequences:
      outputs = last_output

    if self.return_state:
      if not isinstance(states, (list, tuple)):
        states = [states]
      else:
        states = list(states)
      return [outputs] + states
    return outputs
Ejemplo n.º 32
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def SSD300(input_shape, num_classes=21):
    """SSD300 architecture.

    # Arguments
        input_shape: Shape of the input image,
            expected to be either (300, 300, 3) or (3, 300, 300)(not tested).
        num_classes: Number of classes including background.

    # References
        https://arxiv.org/abs/1512.02325
    """
    net = {}
    # Block 1
    input_tensor = input_tensor = Input(shape=input_shape)
    img_size = (input_shape[1], input_shape[0])
    net['input'] = input_tensor
    net['conv1_1'] = Convolution2D(64, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv1_1')(net['input'])

    net['conv1_2'] = Convolution2D(64, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv1_2')(net['conv1_1'])

    net['pool1'] = MaxPooling2D((2, 2),
                                strides=(2, 2),
                                padding='same',
                                name='pool1')(net['conv1_2'])
    # Block 2
    net['conv2_1'] = Convolution2D(128, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv2_1')(net['pool1'])

    net['conv2_2'] = Convolution2D(128, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv2_2')(net['conv2_1'])
    net['pool2'] = MaxPooling2D((2, 2),
                                strides=(2, 2),
                                padding='same',
                                name='pool2')(net['conv2_2'])

    # Block 3
    net['conv3_1'] = Convolution2D(256, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv3_1')(net['pool2'])
    net['conv3_2'] = Convolution2D(256, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv3_2')(net['conv3_1'])
    net['conv3_3'] = Convolution2D(256, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv3_3')(net['conv3_2'])
    net['pool3'] = MaxPooling2D((2, 2),
                                strides=(2, 2),
                                padding='same',
                                name='pool3')(net['conv3_3'])
    # Block 4
    net['conv4_1'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv4_1')(net['pool3'])
    net['conv4_2'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv4_2')(net['conv4_1'])
    net['conv4_3'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv4_3')(net['conv4_2'])
    net['pool4'] = MaxPooling2D((2, 2),
                                strides=(2, 2),
                                padding='same',
                                name='pool4')(net['conv4_3'])
    # Block 5
    net['conv5_1'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv5_1')(net['pool4'])
    net['conv5_2'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv5_2')(net['conv5_1'])
    net['conv5_3'] = Convolution2D(512, (3, 3),
                                   activation='relu',
                                   padding='same',
                                   name='conv5_3')(net['conv5_2'])
    net['pool5'] = MaxPooling2D((3, 3),
                                strides=(1, 1),
                                padding='same',
                                name='pool5')(net['conv5_3'])
    # FC6
    net['fc6'] = Convolution2D(1024, (3, 3),
                               dilation_rate=(6, 6),
                               activation='relu',
                               padding='same',
                               name='fc6')(net['pool5'])
    # x = Dropout(0.5, name='drop6')(x)
    # FC7
    net['fc7'] = Convolution2D(1024, (1, 1),
                               activation='relu',
                               padding='same',
                               name='fc7')(net['fc6'])
    # x = Dropout(0.5, name='drop7')(x)
    # Block 6
    net['conv6_1'] = Convolution2D(256, (1, 1),
                                   activation='relu',
                                   padding='same',
                                   name='conv6_1')(net['fc7'])

    net['conv6_2'] = Convolution2D(512, (3, 3),
                                   strides=(2, 2),
                                   activation='relu',
                                   padding='same',
                                   name='conv6_2')(net['conv6_1'])
    # Block 7
    net['conv7_1'] = Convolution2D(128, (1, 1),
                                   activation='relu',
                                   padding='same',
                                   name='conv7_1')(net['conv6_2'])
    net['conv7_2'] = ZeroPadding2D()(net['conv7_1'])
    net['conv7_2'] = Convolution2D(256, (3, 3),
                                   strides=(2, 2),
                                   activation='relu',
                                   padding='valid',
                                   name='conv7_2')(net['conv7_2'])
    # Block 8
    net['conv8_1'] = Convolution2D(128, (1, 1),
                                   activation='relu',
                                   padding='same',
                                   name='conv8_1')(net['conv7_2'])
    net['conv8_2'] = Convolution2D(256, (3, 3),
                                   strides=(2, 2),
                                   activation='relu',
                                   padding='same',
                                   name='conv8_2')(net['conv8_1'])
    # Last Pool
    net['pool6'] = GlobalAveragePooling2D(name='pool6')(net['conv8_2'])
    # Prediction from conv4_3
    net['conv4_3_norm'] = Normalize(20, name='conv4_3_norm')(net['conv4_3'])
    num_priors = 3
    x = Convolution2D(num_priors * 4, (3, 3),
                      padding='same',
                      name='conv4_3_norm_mbox_loc')(net['conv4_3_norm'])
    net['conv4_3_norm_mbox_loc'] = x
    flatten = Flatten(name='conv4_3_norm_mbox_loc_flat')
    net['conv4_3_norm_mbox_loc_flat'] = flatten(net['conv4_3_norm_mbox_loc'])
    name = 'conv4_3_norm_mbox_conf'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    x = Convolution2D(num_priors * num_classes, (3, 3),
                      padding='same',
                      name=name)(net['conv4_3_norm'])
    net['conv4_3_norm_mbox_conf'] = x
    flatten = Flatten(name='conv4_3_norm_mbox_conf_flat')
    net['conv4_3_norm_mbox_conf_flat'] = flatten(net['conv4_3_norm_mbox_conf'])
    priorbox = PriorBox(img_size,
                        30.0,
                        aspect_ratios=[2],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='conv4_3_norm_mbox_priorbox')
    net['conv4_3_norm_mbox_priorbox'] = priorbox(net['conv4_3_norm'])
    # Prediction from fc7
    num_priors = 6
    net['fc7_mbox_loc'] = Convolution2D(num_priors * 4, (3, 3),
                                        padding='same',
                                        name='fc7_mbox_loc')(net['fc7'])
    flatten = Flatten(name='fc7_mbox_loc_flat')
    net['fc7_mbox_loc_flat'] = flatten(net['fc7_mbox_loc'])
    name = 'fc7_mbox_conf'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    net['fc7_mbox_conf'] = Convolution2D(num_priors * num_classes, (3, 3),
                                         padding='same',
                                         name=name)(net['fc7'])
    flatten = Flatten(name='fc7_mbox_conf_flat')
    net['fc7_mbox_conf_flat'] = flatten(net['fc7_mbox_conf'])
    priorbox = PriorBox(img_size,
                        60.0,
                        max_size=114.0,
                        aspect_ratios=[2, 3],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='fc7_mbox_priorbox')
    net['fc7_mbox_priorbox'] = priorbox(net['fc7'])
    # Prediction from conv6_2
    num_priors = 6
    x = Convolution2D(num_priors * 4, (3, 3),
                      padding='same',
                      name='conv6_2_mbox_loc')(net['conv6_2'])
    net['conv6_2_mbox_loc'] = x
    flatten = Flatten(name='conv6_2_mbox_loc_flat')
    net['conv6_2_mbox_loc_flat'] = flatten(net['conv6_2_mbox_loc'])
    name = 'conv6_2_mbox_conf'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    x = Convolution2D(num_priors * num_classes, (3, 3),
                      padding='same',
                      name=name)(net['conv6_2'])
    net['conv6_2_mbox_conf'] = x
    flatten = Flatten(name='conv6_2_mbox_conf_flat')
    net['conv6_2_mbox_conf_flat'] = flatten(net['conv6_2_mbox_conf'])
    priorbox = PriorBox(img_size,
                        114.0,
                        max_size=168.0,
                        aspect_ratios=[2, 3],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='conv6_2_mbox_priorbox')
    net['conv6_2_mbox_priorbox'] = priorbox(net['conv6_2'])
    # Prediction from conv7_2
    num_priors = 6
    x = Convolution2D(num_priors * 4, (3, 3),
                      padding='same',
                      name='conv7_2_mbox_loc')(net['conv7_2'])
    net['conv7_2_mbox_loc'] = x
    flatten = Flatten(name='conv7_2_mbox_loc_flat')
    net['conv7_2_mbox_loc_flat'] = flatten(net['conv7_2_mbox_loc'])
    name = 'conv7_2_mbox_conf'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    x = Convolution2D(num_priors * num_classes, (3, 3),
                      padding='same',
                      name=name)(net['conv7_2'])
    net['conv7_2_mbox_conf'] = x
    flatten = Flatten(name='conv7_2_mbox_conf_flat')
    net['conv7_2_mbox_conf_flat'] = flatten(net['conv7_2_mbox_conf'])
    priorbox = PriorBox(img_size,
                        168.0,
                        max_size=222.0,
                        aspect_ratios=[2, 3],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='conv7_2_mbox_priorbox')
    net['conv7_2_mbox_priorbox'] = priorbox(net['conv7_2'])
    # Prediction from conv8_2
    num_priors = 6
    x = Convolution2D(num_priors * 4, (3, 3),
                      padding='same',
                      name='conv8_2_mbox_loc')(net['conv8_2'])
    net['conv8_2_mbox_loc'] = x
    flatten = Flatten(name='conv8_2_mbox_loc_flat')
    net['conv8_2_mbox_loc_flat'] = flatten(net['conv8_2_mbox_loc'])
    name = 'conv8_2_mbox_conf'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    x = Convolution2D(num_priors * num_classes, (3, 3),
                      padding='same',
                      name=name)(net['conv8_2'])
    net['conv8_2_mbox_conf'] = x
    flatten = Flatten(name='conv8_2_mbox_conf_flat')
    net['conv8_2_mbox_conf_flat'] = flatten(net['conv8_2_mbox_conf'])
    priorbox = PriorBox(img_size,
                        222.0,
                        max_size=276.0,
                        aspect_ratios=[2, 3],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='conv8_2_mbox_priorbox')
    net['conv8_2_mbox_priorbox'] = priorbox(net['conv8_2'])
    # Prediction from pool6
    num_priors = 6
    x = Dense(num_priors * 4, name='pool6_mbox_loc_flat')(net['pool6'])
    net['pool6_mbox_loc_flat'] = x
    name = 'pool6_mbox_conf_flat'
    if num_classes != 21:
        name += '_{}'.format(num_classes)
    x = Dense(num_priors * num_classes, name=name)(net['pool6'])
    net['pool6_mbox_conf_flat'] = x
    priorbox = PriorBox(img_size,
                        276.0,
                        max_size=330.0,
                        aspect_ratios=[2, 3],
                        variances=[0.1, 0.1, 0.2, 0.2],
                        name='pool6_mbox_priorbox')
    target_shape = (1, 1, 256)
    net['pool6_reshaped'] = Reshape(target_shape,
                                    name='pool6_reshaped')(net['pool6'])
    net['pool6_mbox_priorbox'] = priorbox(net['pool6_reshaped'])
    # Gather all predictions
    net['mbox_loc'] = concatenate([
        net['conv4_3_norm_mbox_loc_flat'], net['fc7_mbox_loc_flat'],
        net['conv6_2_mbox_loc_flat'], net['conv7_2_mbox_loc_flat'],
        net['conv8_2_mbox_loc_flat'], net['pool6_mbox_loc_flat']
    ],
                                  axis=1,
                                  name='mbox_loc')
    net['mbox_conf'] = concatenate([
        net['conv4_3_norm_mbox_conf_flat'], net['fc7_mbox_conf_flat'],
        net['conv6_2_mbox_conf_flat'], net['conv7_2_mbox_conf_flat'],
        net['conv8_2_mbox_conf_flat'], net['pool6_mbox_conf_flat']
    ],
                                   axis=1,
                                   name='mbox_conf')
    net['mbox_priorbox'] = concatenate([
        net['conv4_3_norm_mbox_priorbox'], net['fc7_mbox_priorbox'],
        net['conv6_2_mbox_priorbox'], net['conv7_2_mbox_priorbox'],
        net['conv8_2_mbox_priorbox'], net['pool6_mbox_priorbox']
    ],
                                       axis=1,
                                       name='mbox_priorbox')
    num_boxes = K.int_shape(net['mbox_loc'])[-1] // 4
    net['mbox_loc'] = Reshape((num_boxes, 4),
                              name='mbox_loc_final')(net['mbox_loc'])
    net['mbox_conf'] = Reshape((num_boxes, num_classes),
                               name='mbox_conf_logits')(net['mbox_conf'])
    net['mbox_conf'] = Activation('softmax',
                                  name='mbox_conf_final')(net['mbox_conf'])
    net['predictions'] = concatenate(
        [net['mbox_loc'], net['mbox_conf'], net['mbox_priorbox']],
        axis=2,
        #axis = 0,
        name='predictions')
    model = Model(net['input'], net['predictions'])
    return model
Ejemplo n.º 33
0
  def add(self, layer):
    """Adds a layer instance on top of the layer stack.

    Arguments:
        layer: layer instance.

    Raises:
        TypeError: If `layer` is not a layer instance.
        ValueError: In case the `layer` argument does not
            know its input shape.
        ValueError: In case the `layer` argument has
            multiple output tensors, or is already connected
            somewhere else (forbidden in `Sequential` models).
    """
    if not isinstance(layer, Layer):
      raise TypeError('The added layer must be '
                      'an instance of class Layer. '
                      'Found: ' + str(layer))
    if not self.outputs:
      # first layer in model: check that it is an input layer
      if not layer.inbound_nodes:
        # create an input layer
        if not hasattr(layer, 'batch_input_shape'):
          raise ValueError('The first layer in a '
                           'Sequential model must '
                           'get an `input_shape` or '
                           '`batch_input_shape` argument.')
        # Instantiate the input layer.
        x = Input(
            batch_shape=layer.batch_input_shape,
            dtype=layer.dtype,
            name=layer.name + '_input')
        # This will build the current layer
        # and create the node connecting the current layer
        # to the input layer we just created.
        layer(x)

      if len(layer.inbound_nodes) != 1:
        raise ValueError('A layer added to a Sequential model must '
                         'not already be connected somewhere else. '
                         'Model received layer ' + layer.name + ' which has ' +
                         str(len(layer.inbound_nodes)) +
                         ' pre-existing inbound connections.')

      if len(layer.inbound_nodes[0].output_tensors) != 1:
        raise ValueError('All layers in a Sequential model '
                         'should have a single output tensor. '
                         'For multi-output layers, '
                         'use the functional API.')

      self.outputs = [layer.inbound_nodes[0].output_tensors[0]]
      self.inputs = topology.get_source_inputs(self.outputs[0])

      # We create an input node, which we will keep updated
      # as we add more layers
      topology.Node(
          outbound_layer=self,
          inbound_layers=[],
          node_indices=[],
          tensor_indices=[],
          input_tensors=self.inputs,
          output_tensors=self.outputs,
          # no model-level masking for now
          input_masks=[None for _ in self.inputs],
          output_masks=[None])
    else:
      output_tensor = layer(self.outputs[0])
      if isinstance(output_tensor, list):
        raise TypeError('All layers in a Sequential model '
                        'should have a single output tensor. '
                        'For multi-output layers, '
                        'use the functional API.')
      self.outputs = [output_tensor]
      # update self.inbound_nodes
      self.inbound_nodes[0].output_tensors = self.outputs
      self.inbound_nodes[0].output_shapes = [K.int_shape(self.outputs[0])]

    self.layers.append(layer)
    self.built = False
Ejemplo n.º 34
0
  def set_model(self, model):
    self.model = model
    self.sess = K.get_session()
    if self.histogram_freq and self.merged is None:
      for layer in self.model.layers:
        for weight in layer.weights:
          mapped_weight_name = weight.name.replace(':', '_')
          tf_summary.histogram(mapped_weight_name, weight)
          if self.write_grads:
            grads = model.optimizer.get_gradients(model.total_loss, weight)
            tf_summary.histogram('{}_grad'.format(mapped_weight_name), grads)
          if self.write_images:
            w_img = array_ops.squeeze(weight)
            shape = K.int_shape(w_img)
            if len(shape) == 2:  # dense layer kernel case
              if shape[0] > shape[1]:
                w_img = array_ops.transpose(w_img)
                shape = K.int_shape(w_img)
              w_img = array_ops.reshape(w_img, [1, shape[0], shape[1], 1])
            elif len(shape) == 3:  # convnet case
              if K.image_data_format() == 'channels_last':
                # switch to channels_first to display
                # every kernel as a separate image
                w_img = array_ops.transpose(w_img, perm=[2, 0, 1])
                shape = K.int_shape(w_img)
              w_img = array_ops.reshape(w_img,
                                        [shape[0], shape[1], shape[2], 1])
            elif len(shape) == 1:  # bias case
              w_img = array_ops.reshape(w_img, [1, shape[0], 1, 1])
            else:
              # not possible to handle 3D convnets etc.
              continue

            shape = K.int_shape(w_img)
            assert len(shape) == 4 and shape[-1] in [1, 3, 4]
            tf_summary.image(mapped_weight_name, w_img)

        if hasattr(layer, 'output'):
          tf_summary.histogram('{}_out'.format(layer.name), layer.output)
    self.merged = tf_summary.merge_all()

    if self.write_graph:
      self.writer = tf_summary.FileWriter(self.log_dir, self.sess.graph)
    else:
      self.writer = tf_summary.FileWriter(self.log_dir)

    if self.embeddings_freq:
      embeddings_layer_names = self.embeddings_layer_names

      if not embeddings_layer_names:
        embeddings_layer_names = [
            layer.name for layer in self.model.layers
            if type(layer).__name__ == 'Embedding'
        ]

      embeddings = {
          layer.name: layer.weights[0]
          for layer in self.model.layers if layer.name in embeddings_layer_names
      }

      self.saver = saver_lib.Saver(list(embeddings.values()))

      embeddings_metadata = {}

      if not isinstance(self.embeddings_metadata, str):
        embeddings_metadata = self.embeddings_metadata
      else:
        embeddings_metadata = {
            layer_name: self.embeddings_metadata
            for layer_name in embeddings.keys()
        }

      config = projector.ProjectorConfig()
      self.embeddings_ckpt_path = os.path.join(self.log_dir,
                                               'keras_embedding.ckpt')

      for layer_name, tensor in embeddings.items():
        embedding = config.embeddings.add()
        embedding.tensor_name = tensor.name

        if layer_name in embeddings_metadata:
          embedding.metadata_path = embeddings_metadata[layer_name]

      projector.visualize_embeddings(self.writer, config)