The Sparse convolution2d layer calculates the output based on the input, filter
and strides, paddings, dilations, groups parameters. Input(Input) and
Output(Output) are multidimensional SparseCooTensors with a shape of
:math:`[N, H, W, C]` . Where N is batch size, C is the number of
channels, H is the height of the feature,
and W is the width of the feature. If bias attribution is provided,
bias is added to the output of the convolution.
For each input :math:`X`, the equation is:
.. math::
Out = W \ast X + b
In the above equation:
* :math:`X`: Input value, a tensor with NHWC format.
* :math:`W`: Filter value, a tensor with HWCM format.
* :math:`\\ast`: Convolution operation.
* :math:`b`: Bias value, a 1-D tensor with shape [M].
* :math:`Out`: Output value, the shape of :math:`Out` and :math:`X` may be different.
Parameters:
in_channels(int): The number of input channels in the input image.
out_channels(int): The number of output channels produced by the convolution.
kernel_size(int|list|tuple): The size of the convolving kernel.
stride(int|list|tuple, optional): The stride size. If stride is a list/tuple, it must
contain three integers, (stride_H, stride_W). Otherwise, the
stride_H = stride_W = stride. The default value is 1.
padding(int|str|tuple|list, optional): The padding size. Padding coule be in one of the following forms.
1. a string in ['valid', 'same'].
2. an int, which means each spartial dimension(height, width) is zero paded by size of `padding`
3. a list[int] or tuple[int] whose length is the number of spartial dimensions, which contains the amount of padding on each side for each spartial dimension. It has the form [pad_d1, pad_d2, ...].
4. a list[int] or tuple[int] whose length is 2 * number of spartial dimensions. It has the form [pad_before, pad_after, pad_before, pad_after, ...] for all spartial dimensions.
5. a list or tuple of pairs of ints. It has the form [[pad_before, pad_after], [pad_before, pad_after], ...].
Note that, the batch dimension and channel dimension are also included. Each pair of integers correspond to the amount of padding for a dimension of the input. Padding in batch dimension and channel dimension should be [0, 0] or (0, 0).
The default value is 0.
dilation(int|list|tuple, optional): The dilation size. If dilation is a list/tuple, it must
contain three integers, (dilation_H, dilation_W). Otherwise, the
dilation_H = dilation_W = dilation. The default value is 1.
groups(int, optional): The groups number of the Conv2D Layer. According to grouped
convolution in Alex Krizhevsky's Deep CNN paper: when group=2,
the first half of the filters is only connected to the first half
of the input channels, while the second half of the filters is only
connected to the second half of the input channels. The default value is 1, currently, only support groups=1.
padding_mode(str, optional): ``'zeros'``, ``'reflect'``, ``'replicate'`` or ``'circular'``. Currently only support ``'zeros'``.
weight_attr(ParamAttr, optional): The parameter attribute for learnable parameters/weights
of conv2d. If it is set to None or one attribute of ParamAttr, conv2d
will create ParamAttr as param_attr. If it is set to None, the parameter
is initialized with :math:`Normal(0.0, std)`, and the :math:`std` is
:math:`(\frac{2.0 }{filter\_elem\_num})^{0.5}`. The default value is None.
bias_attr(ParamAttr|bool, optional): The parameter attribute for the bias of conv2d.
If it is set to False, no bias will be added to the output units.
If it is set to None or one attribute of ParamAttr, conv2d
will create ParamAttr as bias_attr. If the Initializer of the bias_attr
is not set, the bias is initialized zero. The default value is None.
data_format(str, optional): Data format that specifies the layout of input.
It can be "NCHW" or "NHWC". Currently, only support "NHWC".
Attribute:
**weight** (Parameter): the learnable weights of filters of this layer.
**bias** (Parameter): the learnable bias of this layer.
The submanifold sparse convolution2d layer calculates the output based on the input, filter
and strides, paddings, dilations, groups parameters. Input(Input) and
Output(Output) are multidimensional SparseCooTensors with a shape of
:math:`[N, H, W, C]` . Where N is batch size, C is the number of
channels, H is the height of the feature,
and W is the width of the feature. If bias attribution is provided,
bias is added to the output of the convolution.
For each input :math:`X`, the equation is:
.. math::
Out = W \ast X + b
In the above equation:
* :math:`X`: Input value, a tensor with NDHWC format.
* :math:`W`: Filter value, a tensor with DHWCM format.
* :math:`\\ast`: Submanifold Convolution operation, refer to the paper: https://arxiv.org/abs/1706.01307.
* :math:`b`: Bias value, a 1-D tensor with shape [M].
* :math:`Out`: Output value, the shape of :math:`Out` and :math:`X` may be different.
Parameters:
in_channels(int): The number of input channels in the input image.
out_channels(int): The number of output channels produced by the convolution.
kernel_size(int|list|tuple): The size of the convolving kernel.
stride(int|list|tuple, optional): The stride size. If stride is a list/tuple, it must
contain two integers, (stride_H, stride_W). Otherwise, the
stride_H = stride_W = stride. The default value is 1.
padding(int|str|tuple|list, optional): The padding size. Padding coule be in one of the following forms.
1. a string in ['valid', 'same'].
2. an int, which means each spartial dimension(depth, height, width) is zero paded by size of `padding`
3. a list[int] or tuple[int] whose length is the number of spartial dimensions, which contains the amount of padding on each side for each spartial dimension. It has the form [pad_d1, pad_d2, ...].
4. a list[int] or tuple[int] whose length is 2 * number of spartial dimensions. It has the form [pad_before, pad_after, pad_before, pad_after, ...] for all spartial dimensions.
5. a list or tuple of pairs of ints. It has the form [[pad_before, pad_after], [pad_before, pad_after], ...].
Note that, the batch dimension and channel dimension are also included. Each pair of integers correspond to the amount of padding for a dimension of the input. Padding in batch dimension and channel dimension should be [0, 0] or (0, 0).
The default value is 0.
dilation(int|list|tuple, optional): The dilation size. If dilation is a list/tuple, it must
contain two integers, (dilation_H, dilation_W). Otherwise, the
dilation_H = dilation_W = dilation. The default value is 1.
groups(int, optional): The groups number of the Conv2D Layer. According to grouped
convolution in Alex Krizhevsky's Deep CNN paper: when group=2,
the first half of the filters is only connected to the first half
of the input channels, while the second half of the filters is only
connected to the second half of the input channels. The default value is 1.
padding_mode(str, optional): ``'zeros'``, ``'reflect'``, ``'replicate'`` or ``'circular'``. Currently only support ``'zeros'``.
key(str, optional): the key is used to save or use the same rulebook,
the definition and role of rulebook refers to
https://pdfs.semanticscholar.org/5125/a16039cabc6320c908a4764f32596e018ad3.pdf. The
default value is None.
weight_attr(ParamAttr, optional): The parameter attribute for learnable parameters/weights
of conv2d. If it is set to None or one attribute of ParamAttr, conv2d
will create ParamAttr as param_attr. If it is set to None, the parameter
is initialized with :math:`Normal(0.0, std)`, and the :math:`std` is
:math:`(\frac{2.0 }{filter\_elem\_num})^{0.5}`. The default value is None.
bias_attr(ParamAttr|bool, optional): The parameter attribute for the bias of conv2d.
If it is set to False, no bias will be added to the output units.
If it is set to None or one attribute of ParamAttr, conv2d
will create ParamAttr as bias_attr. If the Initializer of the bias_attr
is not set, the bias is initialized zero. The default value is None.
data_format(str, optional): Data format that specifies the layout of input.
It can be "NCHW" or "NHWC". Currently, only support "NHWC".
Attribute:
**weight** (Parameter): the learnable weights of filters of this layer.
**bias** (Parameter): the learnable bias of this layer.
