# Copyright 2015 The TensorFlow Authors. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # ============================================================================== """Locally-connected layers. """ from __future__ import absolute_import from __future__ import division from __future__ import print_function from tensorflow.python.keras import activations from tensorflow.python.keras import backend as K from tensorflow.python.keras import constraints from tensorflow.python.keras import initializers from tensorflow.python.keras import regularizers from tensorflow.python.keras.engine.base_layer import InputSpec from tensorflow.python.keras.engine.base_layer import Layer from tensorflow.python.keras.utils import conv_utils from tensorflow.python.keras.utils import tf_utils from tensorflow.python.util.tf_export import tf_export @tf_export('keras.layers.LocallyConnected1D') class LocallyConnected1D(Layer): """Locally-connected layer for 1D inputs. The `LocallyConnected1D` layer works similarly to the `Conv1D` layer, except that weights are unshared, that is, a different set of filters is applied at each different patch of the input. Example: ```python # apply a unshared weight convolution 1d of length 3 to a sequence with # 10 timesteps, with 64 output filters model = Sequential() model.add(LocallyConnected1D(64, 3, input_shape=(10, 32))) # now model.output_shape == (None, 8, 64) # add a new conv1d on top model.add(LocallyConnected1D(32, 3)) # now model.output_shape == (None, 6, 32) ``` Arguments: filters: Integer, the dimensionality of the output space (i.e. the number of output filters in the convolution). kernel_size: An integer or tuple/list of a single integer, specifying the length of the 1D convolution window. strides: An integer or tuple/list of a single integer, specifying the stride length of the convolution. Specifying any stride value != 1 is incompatible with specifying any `dilation_rate` value != 1. padding: Currently only supports `"valid"` (case-insensitive). `"same"` may be supported in the future. data_format: A string, one of `channels_last` (default) or `channels_first`. The ordering of the dimensions in the inputs. `channels_last` corresponds to inputs with shape `(batch, length, channels)` while `channels_first` corresponds to inputs with shape `(batch, channels, length)`. It defaults to the `image_data_format` value found in your Keras config file at `~/.keras/keras.json`. If you never set it, then it will be "channels_last". activation: Activation function to use. If you don't specify anything, no activation is applied (ie. "linear" activation: `a(x) = x`). use_bias: Boolean, whether the layer uses a bias vector. kernel_initializer: Initializer for the `kernel` weights matrix. bias_initializer: Initializer for the bias vector. kernel_regularizer: Regularizer function applied to the `kernel` weights matrix. bias_regularizer: Regularizer function applied to the bias vector. activity_regularizer: Regularizer function applied to the output of the layer (its "activation").. kernel_constraint: Constraint function applied to the kernel matrix. bias_constraint: Constraint function applied to the bias vector. Input shape: 3D tensor with shape: `(batch_size, steps, input_dim)` Output shape: 3D tensor with shape: `(batch_size, new_steps, filters)` `steps` value might have changed due to padding or strides. """ def __init__(self, filters, kernel_size, strides=1, padding='valid', data_format=None, activation=None, use_bias=True, kernel_initializer='glorot_uniform', bias_initializer='zeros', kernel_regularizer=None, bias_regularizer=None, activity_regularizer=None, kernel_constraint=None, bias_constraint=None, **kwargs): super(LocallyConnected1D, self).__init__(**kwargs) self.filters = filters self.kernel_size = conv_utils.normalize_tuple(kernel_size, 1, 'kernel_size') self.strides = conv_utils.normalize_tuple(strides, 1, 'strides') self.padding = conv_utils.normalize_padding(padding) if self.padding != 'valid': raise ValueError('Invalid border mode for LocallyConnected1D ' '(only "valid" is supported): ' + padding) self.data_format = conv_utils.normalize_data_format(data_format) self.activation = activations.get(activation) self.use_bias = use_bias self.kernel_initializer = initializers.get(kernel_initializer) self.bias_initializer = initializers.get(bias_initializer) self.kernel_regularizer = regularizers.get(kernel_regularizer) self.bias_regularizer = regularizers.get(bias_regularizer) self.activity_regularizer = regularizers.get(activity_regularizer) self.kernel_constraint = constraints.get(kernel_constraint) self.bias_constraint = constraints.get(bias_constraint) self.input_spec = InputSpec(ndim=3) @tf_utils.shape_type_conversion def build(self, input_shape): if self.data_format == 'channels_first': input_dim, input_length = input_shape[1], input_shape[2] else: input_dim, input_length = input_shape[2], input_shape[1] if input_dim is None: raise ValueError('Axis 2 of input should be fully-defined. ' 'Found shape:', input_shape) self.output_length = conv_utils.conv_output_length( input_length, self.kernel_size[0], self.padding, self.strides[0]) self.kernel_shape = (self.output_length, self.kernel_size[0] * input_dim, self.filters) self.kernel = self.add_weight( shape=self.kernel_shape, initializer=self.kernel_initializer, name='kernel', regularizer=self.kernel_regularizer, constraint=self.kernel_constraint) if self.use_bias: self.bias = self.add_weight( shape=(self.output_length, self.filters), initializer=self.bias_initializer, name='bias', regularizer=self.bias_regularizer, constraint=self.bias_constraint) else: self.bias = None if self.data_format == 'channels_first': self.input_spec = InputSpec(ndim=3, axes={1: input_dim}) else: self.input_spec = InputSpec(ndim=3, axes={-1: input_dim}) self.built = True @tf_utils.shape_type_conversion def compute_output_shape(self, input_shape): if self.data_format == 'channels_first': input_length = input_shape[2] else: input_length = input_shape[1] length = conv_utils.conv_output_length(input_length, self.kernel_size[0], self.padding, self.strides[0]) if self.data_format == 'channels_first': return (input_shape[0], self.filters, length) elif self.data_format == 'channels_last': return (input_shape[0], length, self.filters) def call(self, inputs): output = K.local_conv(inputs, self.kernel, self.kernel_size, self.strides, (self.output_length,), self.data_format) if self.use_bias: output = K.bias_add(output, self.bias, data_format=self.data_format) output = self.activation(output) return output def get_config(self): config = { 'filters': self.filters, 'kernel_size': self.kernel_size, 'strides': self.strides, 'padding': self.padding, 'data_format': self.data_format, 'activation': activations.serialize(self.activation), 'use_bias': self.use_bias, 'kernel_initializer': initializers.serialize(self.kernel_initializer), 'bias_initializer': initializers.serialize(self.bias_initializer), 'kernel_regularizer': regularizers.serialize(self.kernel_regularizer), 'bias_regularizer': regularizers.serialize(self.bias_regularizer), 'activity_regularizer': regularizers.serialize(self.activity_regularizer), 'kernel_constraint': constraints.serialize(self.kernel_constraint), 'bias_constraint': constraints.serialize(self.bias_constraint) } base_config = super(LocallyConnected1D, self).get_config() return dict(list(base_config.items()) + list(config.items())) @tf_export('keras.layers.LocallyConnected2D') class LocallyConnected2D(Layer): """Locally-connected layer for 2D inputs. The `LocallyConnected2D` layer works similarly to the `Conv2D` layer, except that weights are unshared, that is, a different set of filters is applied at each different patch of the input. Examples: ```python # apply a 3x3 unshared weights convolution with 64 output filters on a 32x32 image # with `data_format="channels_last"`: model = Sequential() model.add(LocallyConnected2D(64, (3, 3), input_shape=(32, 32, 3))) # now model.output_shape == (None, 30, 30, 64) # notice that this layer will consume (30*30)*(3*3*3*64) + (30*30)*64 parameters # add a 3x3 unshared weights convolution on top, with 32 output filters: model.add(LocallyConnected2D(32, (3, 3))) # now model.output_shape == (None, 28, 28, 32) ``` Arguments: filters: Integer, the dimensionality of the output space (i.e. the number of output filters in the convolution). kernel_size: An integer or tuple/list of 2 integers, specifying the width and height of the 2D convolution window. Can be a single integer to specify the same value for all spatial dimensions. strides: An integer or tuple/list of 2 integers, specifying the strides of the convolution along the width and height. Can be a single integer to specify the same value for all spatial dimensions. padding: Currently only support `"valid"` (case-insensitive). `"same"` will be supported in future. data_format: A string, one of `channels_last` (default) or `channels_first`. The ordering of the dimensions in the inputs. `channels_last` corresponds to inputs with shape `(batch, height, width, channels)` while `channels_first` corresponds to inputs with shape `(batch, channels, height, width)`. It defaults to the `image_data_format` value found in your Keras config file at `~/.keras/keras.json`. If you never set it, then it will be "channels_last". activation: Activation function to use. If you don't specify anything, no activation is applied (ie. "linear" activation: `a(x) = x`). use_bias: Boolean, whether the layer uses a bias vector. kernel_initializer: Initializer for the `kernel` weights matrix. bias_initializer: Initializer for the bias vector. kernel_regularizer: Regularizer function applied to the `kernel` weights matrix. bias_regularizer: Regularizer function applied to the bias vector. activity_regularizer: Regularizer function applied to the output of the layer (its "activation").. kernel_constraint: Constraint function applied to the kernel matrix. bias_constraint: Constraint function applied to the bias vector. Input shape: 4D tensor with shape: `(samples, channels, rows, cols)` if data_format='channels_first' or 4D tensor with shape: `(samples, rows, cols, channels)` if data_format='channels_last'. Output shape: 4D tensor with shape: `(samples, filters, new_rows, new_cols)` if data_format='channels_first' or 4D tensor with shape: `(samples, new_rows, new_cols, filters)` if data_format='channels_last'. `rows` and `cols` values might have changed due to padding. """ def __init__(self, filters, kernel_size, strides=(1, 1), padding='valid', data_format=None, activation=None, use_bias=True, kernel_initializer='glorot_uniform', bias_initializer='zeros', kernel_regularizer=None, bias_regularizer=None, activity_regularizer=None, kernel_constraint=None, bias_constraint=None, **kwargs): super(LocallyConnected2D, self).__init__(**kwargs) self.filters = filters self.kernel_size = conv_utils.normalize_tuple(kernel_size, 2, 'kernel_size') self.strides = conv_utils.normalize_tuple(strides, 2, 'strides') self.padding = conv_utils.normalize_padding(padding) if self.padding != 'valid': raise ValueError('Invalid border mode for LocallyConnected2D ' '(only "valid" is supported): ' + padding) self.data_format = conv_utils.normalize_data_format(data_format) self.activation = activations.get(activation) self.use_bias = use_bias self.kernel_initializer = initializers.get(kernel_initializer) self.bias_initializer = initializers.get(bias_initializer) self.kernel_regularizer = regularizers.get(kernel_regularizer) self.bias_regularizer = regularizers.get(bias_regularizer) self.activity_regularizer = regularizers.get(activity_regularizer) self.kernel_constraint = constraints.get(kernel_constraint) self.bias_constraint = constraints.get(bias_constraint) self.input_spec = InputSpec(ndim=4) @tf_utils.shape_type_conversion def build(self, input_shape): if self.data_format == 'channels_last': input_row, input_col = input_shape[1:-1] input_filter = input_shape[3] else: input_row, input_col = input_shape[2:] input_filter = input_shape[1] if input_row is None or input_col is None: raise ValueError('The spatial dimensions of the inputs to ' ' a LocallyConnected2D layer ' 'should be fully-defined, but layer received ' 'the inputs shape ' + str(input_shape)) output_row = conv_utils.conv_output_length(input_row, self.kernel_size[0], self.padding, self.strides[0]) output_col = conv_utils.conv_output_length(input_col, self.kernel_size[1], self.padding, self.strides[1]) self.output_row = output_row self.output_col = output_col self.kernel_shape = ( output_row * output_col, self.kernel_size[0] * self.kernel_size[1] * input_filter, self.filters) self.kernel = self.add_weight( shape=self.kernel_shape, initializer=self.kernel_initializer, name='kernel', regularizer=self.kernel_regularizer, constraint=self.kernel_constraint) if self.use_bias: self.bias = self.add_weight( shape=(output_row, output_col, self.filters), initializer=self.bias_initializer, name='bias', regularizer=self.bias_regularizer, constraint=self.bias_constraint) else: self.bias = None if self.data_format == 'channels_first': self.input_spec = InputSpec(ndim=4, axes={1: input_filter}) else: self.input_spec = InputSpec(ndim=4, axes={-1: input_filter}) self.built = True @tf_utils.shape_type_conversion def compute_output_shape(self, input_shape): if self.data_format == 'channels_first': rows = input_shape[2] cols = input_shape[3] elif self.data_format == 'channels_last': rows = input_shape[1] cols = input_shape[2] rows = conv_utils.conv_output_length(rows, self.kernel_size[0], self.padding, self.strides[0]) cols = conv_utils.conv_output_length(cols, self.kernel_size[1], self.padding, self.strides[1]) if self.data_format == 'channels_first': return (input_shape[0], self.filters, rows, cols) elif self.data_format == 'channels_last': return (input_shape[0], rows, cols, self.filters) def call(self, inputs): output = K.local_conv(inputs, self.kernel, self.kernel_size, self.strides, (self.output_row, self.output_col), self.data_format) if self.use_bias: output = K.bias_add(output, self.bias, data_format=self.data_format) output = self.activation(output) return output def get_config(self): config = { 'filters': self.filters, 'kernel_size': self.kernel_size, 'strides': self.strides, 'padding': self.padding, 'data_format': self.data_format, 'activation': activations.serialize(self.activation), 'use_bias': self.use_bias, 'kernel_initializer': initializers.serialize(self.kernel_initializer), 'bias_initializer': initializers.serialize(self.bias_initializer), 'kernel_regularizer': regularizers.serialize(self.kernel_regularizer), 'bias_regularizer': regularizers.serialize(self.bias_regularizer), 'activity_regularizer': regularizers.serialize(self.activity_regularizer), 'kernel_constraint': constraints.serialize(self.kernel_constraint), 'bias_constraint': constraints.serialize(self.bias_constraint) } base_config = super(LocallyConnected2D, self).get_config() return dict(list(base_config.items()) + list(config.items()))