TensorFlow 1 version | View source on GitHub |
Depthwise separable 2D convolution.
Inherits From: Conv2D
, Layer
, Module
tf.keras.layers.DepthwiseConv2D(
kernel_size, strides=(1, 1), padding='valid', depth_multiplier=1,
data_format=None, dilation_rate=(1, 1), activation=None, use_bias=True,
depthwise_initializer='glorot_uniform',
bias_initializer='zeros', depthwise_regularizer=None,
bias_regularizer=None, activity_regularizer=None, depthwise_constraint=None,
bias_constraint=None, **kwargs
)
Depthwise Separable convolutions consist of performing
just the first step in a depthwise spatial convolution
(which acts on each input channel separately).
The depth_multiplier
argument controls how many
output channels are generated per input channel in the depthwise step.
Arguments | |
---|---|
kernel_size
|
An integer or tuple/list of 2 integers, specifying the height and width 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 height and width.
Can be a single integer to specify the same value for
all spatial dimensions.
Specifying any stride value != 1 is incompatible with specifying
any dilation_rate value != 1.
|
padding
|
one of 'valid' or 'same' (case-insensitive).
"valid" means no padding. "same" results in padding evenly to
the left/right or up/down of the input such that output has the same
height/width dimension as the input.
|
depth_multiplier
|
The number of depthwise convolution output channels
for each input channel.
The total number of depthwise convolution output
channels will be equal to filters_in * depth_multiplier .
|
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_size, height, width, channels) while channels_first
corresponds to inputs with shape
(batch_size, 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'.
|
dilation_rate
|
An integer or tuple/list of 2 integers, specifying
the dilation rate to use for dilated convolution.
Currently, specifying any dilation_rate value != 1 is
incompatible with specifying any strides value != 1.
|
activation
|
Activation function to use.
If you don't specify anything, no activation is applied (
see keras.activations ).
|
use_bias
|
Boolean, whether the layer uses a bias vector. |
depthwise_initializer
|
Initializer for the depthwise kernel matrix (
see keras.initializers ).
|
bias_initializer
|
Initializer for the bias vector (
see keras.initializers ).
|
depthwise_regularizer
|
Regularizer function applied to
the depthwise kernel matrix (see keras.regularizers ).
|
bias_regularizer
|
Regularizer function applied to the bias vector (
see keras.regularizers ).
|
activity_regularizer
|
Regularizer function applied to
the output of the layer (its 'activation') (
see keras.regularizers ).
|
depthwise_constraint
|
Constraint function applied to
the depthwise kernel matrix (
see keras.constraints ).
|
bias_constraint
|
Constraint function applied to the bias vector (
see keras.constraints ).
|
Input shape:
4D tensor with shape:
[batch_size, channels, rows, cols]
if data_format='channels_first'
or 4D tensor with shape:
[batch_size, rows, cols, channels]
if data_format='channels_last'.
Output shape:
4D tensor with shape:
[batch_size, filters, new_rows, new_cols]
if data_format='channels_first'
or 4D tensor with shape:
[batch_size, new_rows, new_cols, filters]
if data_format='channels_last'.
rows
and cols
values might have changed due to padding.
Returns | |
---|---|
A tensor of rank 4 representing
activation(depthwiseconv2d(inputs, kernel) + bias) .
|
Raises | |
---|---|
ValueError
|
if padding is "causal".
|
ValueError
|
when both strides > 1 and dilation_rate > 1.
|