Python backend.squeeze方法代码示例

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def step(self, x, states):  
        h = states[0]
        # states[1] necessary?
        
        # comes from the constants
        X_static = states[-2]
        # equals K.dot(static_x, self._W1) + self._b2 with X.shape=[bs, L, static_input_dim]
        total_x_static_prod = states[-1]

        # expand dims to add the vector which is only valid for this time step
        # to total_x_prod which is valid for all time steps
        hw = K.expand_dims(K.dot(h, self._W2), 1)
        additive_atn = total_x_static_prod + hw
        attention = K.softmax(K.dot(additive_atn, self._V), axis=1)
        static_x_weighted = K.sum(attention * X_static, [1])
        
        x = K.dot(K.concatenate([x, static_x_weighted], 1), self._W3) + self._b3

        h, new_states = self.layer.cell.call(x, states[:-2])
        
        # append attention to the states to "smuggle" it out of the RNN wrapper
        attention = K.squeeze(attention, -1)
        h = K.concatenate([h, attention])

        return h, new_states 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def rpn_class_loss_graph(rpn_match, rpn_class_logits):
    """RPN anchor classifier loss.
    rpn_match: [batch, anchors, 1]. Anchor match type. 1=positive,
               -1=negative, 0=neutral anchor.
    rpn_class_logits: [batch, anchors, 2]. RPN classifier logits for FG/BG.
    """
    # Squeeze last dim to simplify
    rpn_match = tf.squeeze(rpn_match, -1)
    # Get anchor classes. Convert the -1/+1 match to 0/1 values.
    anchor_class = K.cast(K.equal(rpn_match, 1), tf.int32)
    # Positive and Negative anchors contribute to the loss,
    # but neutral anchors (match value = 0) don't.
    indices = tf.where(K.not_equal(rpn_match, 0))
    # Pick rows that contribute to the loss and filter out the rest.
    rpn_class_logits = tf.gather_nd(rpn_class_logits, indices)
    anchor_class = tf.gather_nd(anchor_class, indices)
    # Cross entropy loss
    loss = K.sparse_categorical_crossentropy(target=anchor_class,
                                             output=rpn_class_logits,
                                             from_logits=True)
    loss = K.switch(tf.size(loss) > 0, K.mean(loss), tf.constant(0.0))
    return loss 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def rpn_class_loss_graph(rpn_match, rpn_class_logits):
    """RPN anchor classifier loss.

    rpn_match: [batch, anchors, 1]. Anchor match type. 1=positive,
               -1=negative, 0=neutral anchor.
    rpn_class_logits: [batch, anchors, 2]. RPN classifier logits for FG/BG.
    """
    # Squeeze last dim to simplify
    rpn_match = tf.squeeze(rpn_match, -1)
    # Get anchor classes. Convert the -1/+1 match to 0/1 values.
    anchor_class = K.cast(K.equal(rpn_match, 1), tf.int32)
    # Positive and Negative anchors contribute to the loss,
    # but neutral anchors (match value = 0) don't.
    indices = tf.where(K.not_equal(rpn_match, 0))
    # Pick rows that contribute to the loss and filter out the rest.
    rpn_class_logits = tf.gather_nd(rpn_class_logits, indices)
    anchor_class = tf.gather_nd(anchor_class, indices)
    # Cross entropy loss
    loss = K.sparse_categorical_crossentropy(target=anchor_class,
                                             output=rpn_class_logits,
                                             from_logits=True)
    loss = K.switch(tf.size(loss) > 0, K.mean(loss), tf.constant(0.0))
    return loss 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def step(self, x_input, states):
    	#print "x_input:", x_input, x_input.shape
    	# <TensorType(float32, matrix)>
    	
        input_shape = self.input_spec[0].shape
        en_seq = states[-1]
        _, [h, c] = super(PointerLSTM, self).step(x_input, states[:-1])

        # vt*tanh(W1*e+W2*d)
        dec_seq = K.repeat(h, input_shape[1])
        Eij = time_distributed_dense(en_seq, self.W1, output_dim=1)
        Dij = time_distributed_dense(dec_seq, self.W2, output_dim=1)
        U = self.vt * tanh(Eij + Dij)
        U = K.squeeze(U, 2)

        # make probability tensor
        pointer = softmax(U)
        return pointer, [h, c] 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def rpn_class_loss_graph(rpn_match, rpn_class_logits):
    """RPN anchor classifier loss.

    rpn_match: [batch, anchors, 1]. Anchor match type. 1=positive,
               -1=negative, 0=neutral anchor.
    rpn_class_logits: [batch, anchors, 2]. RPN classifier logits for FG/BG.
    """
    # Squeeze last dim to simplify
    rpn_match = tf.squeeze(rpn_match, -1)
    # Get anchor classes. Convert the -1/+1 match to 0/1 values.
    anchor_class = K.cast(K.equal(rpn_match, 1), tf.int32)
    # Positive and Negative anchors contribute to the loss,
    # but neutral anchors (match value = 0) don't.
    indices = tf.where(K.not_equal(rpn_match, 0))
    # Pick rows that contribute to the loss and filter out the rest.
    rpn_class_logits = tf.gather_nd(rpn_class_logits, indices)
    anchor_class = tf.gather_nd(anchor_class, indices)
    # Crossentropy loss
    loss = K.sparse_categorical_crossentropy(target=anchor_class,
                                             output=rpn_class_logits,
                                             from_logits=True)
    loss = K.switch(tf.size(loss) > 0, K.mean(loss), tf.constant(0.0))
    return loss 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def _backward(gamma, mask):
    '''Backward recurrence of the linear chain crf.'''
    gamma = K.cast(gamma, 'int32')

    def _backward_step(gamma_t, states):
        y_tm1 = K.squeeze(states[0], 0)
        y_t = batch_gather(gamma_t, y_tm1)
        return y_t, [K.expand_dims(y_t, 0)]

    initial_states = [K.expand_dims(K.zeros_like(gamma[:, 0, 0]), 0)]
    _, y_rev, _ = K.rnn(_backward_step,
                        gamma,
                        initial_states,
                        go_backwards=True)
    y = K.reverse(y_rev, 1)

    if mask is not None:
        mask = K.cast(mask, dtype='int32')
        # mask output
        y *= mask
        # set masked values to -1
        y += -(1 - mask)
    return y 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def _target_class_loss(
            self,
            target_class,
            box_scores,
            box_class_probs_logits):
        """ Evaluate target_class_loss w.r.t. the input.

        """
        box_scores = K.squeeze(box_scores, axis=0)
        box_class_probs_logits = K.squeeze(box_class_probs_logits, axis=0)
        import tensorflow as tf
        boi_idx = tf.where(box_scores[:, target_class] > self._score)
        loss_box_class_conf = tf.reduce_mean(
            tf.gather(box_class_probs_logits[:, target_class], boi_idx))

        # Avoid the propagation of nan
        return tf.cond(
            tf.is_nan(loss_box_class_conf),
            lambda: tf.constant(0.),
            lambda: loss_box_class_conf) 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def call(self, x, mask=None):
        # size of x :[batch_size, sel_len, attention_dim]
        # size of u :[batch_size, attention_dim]
        # uit = tanh(xW+b)
        uit = K.tanh(K.bias_add(K.dot(x, self.W), self.b))
        ait = K.dot(uit, self.u)
        ait = K.squeeze(ait, -1)

        ait = K.exp(ait)

        if mask is not None:
            # Cast the mask to floatX to avoid float64 upcasting in theano
            ait *= K.cast(mask, K.floatx())
        ait /= K.cast(K.sum(ait, axis=1, keepdims=True) + K.epsilon(), K.floatx())
        ait = K.expand_dims(ait)
        weighted_input = x * ait
        output = K.sum(weighted_input, axis=1)

        return output 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def preprocess_input(self, inputs, training=None):
        if self.window_size > 1:
            inputs = K.temporal_padding(inputs, (self.window_size - 1, 0))
        inputs = K.expand_dims(inputs, 2)  # add a dummy dimension

        output = K.conv2d(inputs, self.kernel, strides=self.strides,
                          padding='valid',
                          data_format='channels_last')
        output = K.squeeze(output, 2)  # remove the dummy dimension
        if self.use_bias:
            output = K.bias_add(output, self.bias, data_format='channels_last')

        if self.dropout is not None and 0. < self.dropout < 1.:
            z = output[:, :, :self.units]
            f = output[:, :, self.units:2 * self.units]
            o = output[:, :, 2 * self.units:]
            f = K.in_train_phase(1 - _dropout(1 - f, self.dropout), f, training=training)
            return K.concatenate([z, f, o], -1)
        else:
            return output 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def _compute_probabilities(self, energy, previous_attention=None):
        if self.is_monotonic:
            # add presigmoid noise to encourage discreteness
            sigmoid_noise = K.in_train_phase(1., 0.)
            noise = K.random_normal(K.shape(energy), mean=0.0, stddev=sigmoid_noise)
            # encourage discreteness in train
            energy = K.in_train_phase(energy + noise, energy)

            p = K.in_train_phase(K.sigmoid(energy),
                                 K.cast(energy > 0, energy.dtype))
            p = K.squeeze(p, -1)
            p_prev = K.squeeze(previous_attention, -1)
            # monotonic attention function from tensorflow
            at = K.in_train_phase(
                tf.contrib.seq2seq.monotonic_attention(p, p_prev, 'parallel'),
                tf.contrib.seq2seq.monotonic_attention(p, p_prev, 'hard'))
            at = K.expand_dims(at, -1)
        else:
            # softmax
            at = keras.activations.softmax(energy, axis=1)

        return at 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def rpn_class_loss_graph(rpn_match, rpn_class_logits):
    '''RPN anchor classifier loss.

    rpn_match: [batch, anchors, 1]. Anchor match type. 1=positive,
               -1=negative, 0=neutral anchor.
    rpn_class_logits: [batch, anchors, 2]. RPN classifier logits for FG/BG.
    '''
    # Squeeze last dim to simplify
    rpn_match = tf.squeeze(rpn_match, -1)
    # Get anchor classes. Convert the -1/+1 match to 0/1 values.
    anchor_class = K.cast(K.equal(rpn_match, 1), tf.int32)
    # Positive and Negative anchors contribute to the loss,
    # but neutral anchors (match value = 0) don't.
    indices = tf.where(K.not_equal(rpn_match, 0))
    # Pick rows that contribute to the loss and filter out the rest.
    rpn_class_logits = tf.gather_nd(rpn_class_logits, indices)
    anchor_class = tf.gather_nd(anchor_class, indices)
    # Cross entropy loss
    loss = K.sparse_categorical_crossentropy(target=anchor_class,
                                             output=rpn_class_logits,
                                             from_logits=True)
    loss = K.switch(tf.size(loss) > 0, K.mean(loss), tf.constant(0.0))
    return loss 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def rpn_class_loss_graph(rpn_match, rpn_class_logits):
    """RPN anchor classifier loss.

    rpn_match: [batch, anchors, 1]. Anchor match type. 1=positive,
               -1=negative, 0=neutral anchor.
    rpn_class_logits: [batch, anchors, 2]. RPN classifier logits for BG/FG.
    """
    # Squeeze last dim to simplify
    rpn_match = tf.squeeze(rpn_match, -1)
    # Get anchor classes. Convert the -1/+1 match to 0/1 values.
    anchor_class = K.cast(K.equal(rpn_match, 1), tf.int32)
    # Positive and Negative anchors contribute to the loss,
    # but neutral anchors (match value = 0) don't.
    indices = tf.where(K.not_equal(rpn_match, 0))
    # Pick rows that contribute to the loss and filter out the rest.
    rpn_class_logits = tf.gather_nd(rpn_class_logits, indices)
    anchor_class = tf.gather_nd(anchor_class, indices)
    # Cross entropy loss
    loss = K.sparse_categorical_crossentropy(target=anchor_class,
                                             output=rpn_class_logits,
                                             from_logits=True)
    loss = K.switch(tf.size(loss) > 0, K.mean(loss), tf.constant(0.0))
    return loss 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def call(self, inputs, **kwargs):
        """Evaluate YOLO model on given input and return filtered boxes."""
        yolo_outputs = inputs[0:-1]
        input_image_shape = K.squeeze(inputs[-1], axis=0)
        num_layers = len(yolo_outputs)
        anchor_mask = [[6, 7, 8], [3, 4, 5], [0, 1, 2]] if num_layers == 3 else [[3, 4, 5],
                                                                                 [1, 2, 3]]  # default setting
        input_shape = K.shape(yolo_outputs[0])[1:3] * 32
        boxes = []
        box_scores = []
        for l in range(num_layers):
            _boxes, _box_scores = yolo_boxes_and_scores(yolo_outputs[l], self.anchors[anchor_mask[l]], self.num_classes,
                                                        input_shape, input_image_shape)
            boxes.append(_boxes)
            box_scores.append(_box_scores)
        boxes = K.concatenate(boxes, axis=0)
        box_scores = K.concatenate(box_scores, axis=0)
        return [boxes, box_scores] 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def gripper_coordinate_y_pred(y_true, y_pred):
    """ Get the predicted value at the coordinate found in y_true.

    # Arguments

        y_true: [ground_truth_label, y_height_coordinate, x_width_coordinate]
            Shape of y_true is [batch_size, 3].
        y_pred: Predicted values with shape [batch_size, img_height, img_width, 1].
    """
    with K.name_scope(name="gripper_coordinate_y_pred") as scope:
        if keras.backend.ndim(y_true) == 4:
            # sometimes the dimensions are expanded from 2 to 4
            # to meet Keras' expectations.
            # In that case reduce them back to 2
            y_true = K.squeeze(y_true, axis=-1)
            y_true = K.squeeze(y_true, axis=-1)
        yx_coordinate = K.cast(y_true[:, 1:], 'int32')
        yx_shape = K.shape(yx_coordinate)
        sample_index = K.expand_dims(K.arange(yx_shape[0]), axis=-1)
        byx_coordinate = K.concatenate([sample_index, yx_coordinate], axis=-1)

        # maybe need to transpose yx_coordinate?
        gripper_coordinate_y_predicted = tf.gather_nd(y_pred, byx_coordinate)
        return gripper_coordinate_y_predicted 

# 需要导入模块: from keras import backend [as 别名]
# 或者: from keras.backend import squeeze [as 别名]
def gripper_coordinate_y_true(y_true, y_pred=None):
    """ Get the label found in y_true which also contains coordinates.

    # Arguments

        y_true: [ground_truth_label, y_height_coordinate, x_width_coordinate]
            Shape of y_true is [batch_size, 3].
        y_pred: Predicted values with shape [batch_size, img_height, img_width, 1].
    """
    with K.name_scope(name="gripper_coordinate_y_true") as scope:
        if keras.backend.ndim(y_true) == 4:
            # sometimes the dimensions are expanded from 2 to 4
            # to meet Keras' expectations.
            # In that case reduce them back to 2
            y_true = K.squeeze(y_true, axis=-1)
            y_true = K.squeeze(y_true, axis=-1)
        label = K.cast(y_true[:, :1], 'float32')
        return label