On this page
tf.keras.layers.Conv3D
3D convolution layer (e.g. spatial convolution over volumes).
tf.keras.layers.Conv3D(
filters, kernel_size, strides=(1, 1, 1), padding='valid', data_format=None,
dilation_rate=(1, 1, 1), groups=1, 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
)
This layer creates a convolution kernel that is convolved with the layer input to produce a tensor of outputs. If use_bias
is True, a bias vector is created and added to the outputs. Finally, if activation
is not None
, it is applied to the outputs as well.
When using this layer as the first layer in a model, provide the keyword argument input_shape
(tuple of integers, does not include the sample axis), e.g. input_shape=(128, 128, 128, 1)
for 128x128x128 volumes with a single channel, in data_format="channels_last"
.
Examples:
# The inputs are 28x28x28 volumes with a single channel, and the
# batch size is 4
input_shape =(4, 28, 28, 28, 1)
x = tf.random.normal(input_shape)
y = tf.keras.layers.Conv3D(
2, 3, activation='relu', input_shape=input_shape[1:])(x)
print(y.shape)
(4, 26, 26, 26, 2)
# With extended batch shape [4, 7], e.g. a batch of 4 videos of 3D frames,
# with 7 frames per video.
input_shape = (4, 7, 28, 28, 28, 1)
x = tf.random.normal(input_shape)
y = tf.keras.layers.Conv3D(
2, 3, activation='relu', input_shape=input_shape[2:])(x)
print(y.shape)
(4, 7, 26, 26, 26, 2)
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 3 integers, specifying the depth, height and width of the 3D convolution window. Can be a single integer to specify the same value for all spatial dimensions. |
strides |
An integer or tuple/list of 3 integers, specifying the strides of the convolution along each spatial dimension. 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). |
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_shape + (spatial_dim1, spatial_dim2, spatial_dim3, channels) while channels_first corresponds to inputs with shape batch_shape + (channels, spatial_dim1, spatial_dim2, spatial_dim3) . 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 3 integers, specifying the dilation rate to use for dilated convolution. Can be a single integer to specify the same value for all spatial dimensions. Currently, specifying any dilation_rate value != 1 is incompatible with specifying any stride value != 1. |
groups |
A positive integer specifying the number of groups in which the input is split along the channel axis. Each group is convolved separately with filters / groups filters. The output is the concatenation of all the groups results along the channel axis. Input channels and filters must both be divisible by groups . |
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. |
kernel_initializer |
Initializer for the kernel weights matrix (see keras.initializers ). |
bias_initializer |
Initializer for the bias vector (see keras.initializers ). |
kernel_regularizer |
Regularizer function applied to the kernel weights 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 ). |
kernel_constraint |
Constraint function applied to the kernel matrix (see keras.constraints ). |
bias_constraint |
Constraint function applied to the bias vector (see keras.constraints ). |
Input shape:
5+D tensor with shape: batch_shape + (channels, conv_dim1, conv_dim2, conv_dim3)
if data_format='channels_first' or 5+D tensor with shape: batch_shape + (conv_dim1, conv_dim2, conv_dim3, channels)
if data_format='channels_last'.
Output shape:
5+D tensor with shape: batch_shape + (filters, new_conv_dim1, new_conv_dim2, new_conv_dim3)
if data_format='channels_first' or 5+D tensor with shape: batch_shape + (new_conv_dim1, new_conv_dim2, new_conv_dim3, filters)
if data_format='channels_last'. new_conv_dim1
, new_conv_dim2
and new_conv_dim3
values might have changed due to padding.
Returns | |
---|---|
A tensor of rank 5+ representing activation(conv3d(inputs, kernel) + bias) . |
Raises | |
---|---|
ValueError |
if padding is "causal". |
ValueError |
when both strides > 1 and dilation_rate > 1 . |
© 2020 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.3/api_docs/python/tf/keras/layers/Conv3D