mindspore.ops.avg_pool2d

mindspore.ops.avg_pool2d(input_x, kernel_size=1, stride=1, padding=0, ceil_mode=False, count_include_pad=True, divisor_override=0)

Applies a 2D average pooling over an input Tensor which can be regarded as a composition of 2D input planes. Typically the input is of shape \((N_{in}, C_{in}, H_{in}, W_{in})\), outputs regional average in the \((H_{in}, W_{in})\)-dimension. Given kernel size \((k_{h}, k_{w})\) and strides , the operation is as follows.

\[\text{output}(N_i, C_j, h, w) = \frac{1}{k_{h} * k_{w}} \sum_{m=0}^{k_{h}-1} \sum_{n=0}^{k_{w}-1} \text{input}(N_i, C_j, stride[0] \times h + m, stride[1] \times w + n)\]

Warning

kernel_size is in the range [1, 255]. stride is in the range [1, 63].

Parameters

• input_x (Tensor) – Tensor of shape \((N, C_{in}, H_{in}, W_{in})\).

• kernel_size (Union[int, tuple[int]]) – The size of kernel used to take the average value. It is an int number that represents height and width of the kernel, or a tuple of two int numbers that represent height and width respectively. Default: 1 .

• stride (Union[int, tuple[int]]) – The distance of kernel moving, an int number that represents the height and width of movement are both strides, or a tuple of two int numbers that represent height and width of movement respectively. Default: 1 .

• padding (Union(int, tuple[int])) – The pad value to be filled. Default: 0. If padding is an integer, the paddings of top, bottom, left and right are the same, equal to pad. If padding is a tuple of 4 integers, the padding of top, bottom, left and right equal to padding[0], padding[1], padding[2] and padding[3] correspondingly. Default: 0 .

• ceil_mode (bool) – If True, apply ceil instead of floor to compute the output shape. Default: False.

• count_include_pad (bool) – If True, include the zero-padding in the averaging calculation. Default: True .

• divisor_override (int) – If specified, it will be used as divisor in the averaging calculation, otherwise kernel_size will be used. Default: 0, which means not specified.

Returns

Tensor, with shape \((N, C_{out}, H_{out}, W_{out})\).

Raises

• TypeError – If input_x is not an Tensor.

• TypeError – If kernel_size or stride is neither int nor tuple.

• TypeError – If ceil_mode or count_include_pad is not a bool.

• TypeError – If divisor_override is not an int.

• ValueError – If length of shape of input_x is not equal to 4.

• ValueError – If kernel_size or stride is less than 1.

• ValueError – If kernel_size or stride is a tuple whose length is not equal to 2.

• ValueError – If padding is not int nor a tuple whose length is equal to 4.

• ValueError – If value(s) of padding is less than 0.

Supported Platforms:

Ascend GPU CPU

Examples

>>> import mindspore
>>> import numpy as np
>>> from mindspore import Tensor, ops
>>> x = Tensor(np.arange(1 * 3 * 3 * 4).reshape(1, 3, 3, 4), mindspore.float32)
>>> output = ops.avg_pool2d(x, kernel_size=2, stride=1)
>>> print(output)
[[[[ 2.5   3.5   4.5]
   [ 6.5   7.5   8.5]]
  [[14.5  15.5  16.5]
   [18.5  19.5  20.5]]
  [[26.5  27.5  28.5]
   [30.5  31.5  32.5]]]]