tf.keras.layers.MaxPooling2D

2D最大池化层

keras.layers.MaxPooling2D(pool_size=(2, 2), 
                          strides=None, 
                          padding='valid', 
                          data_format=None)

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参数详解

• pool_size: 池化窗口大小
• strides: 池化步长，默认值等于 pool_size
• padding: 'VALID' 或 'SAME'，'VALID'表示无填充，'SAME'表示用0填充
• data_format: 表示输入张量的维度顺序，默认为 [batch, height, width, channel]

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示例

from tensorflow.keras.layers import MaxPool2D
import tensorflow as tf
import numpy as np

# 定义一个最大池化层，用0填充
pool1 = MaxPool2D(pool_size=(2, 2),
                  strides=None,
                  padding='SAME',
                  data_format=None)

# 定义一个最大池化层，不填充
pool2 = MaxPool2D(pool_size=(2, 2),
                  strides=None,
                  padding='VALID',
                  data_format=None)

# 生成一个维度为[64, 101, 101, 3]的矩阵
x = np.random.random((64, 101, 101, 3))

# 转成tensor类型,第一个维度64表示batch
x = tf.convert_to_tensor(x)
print(x.shape) # [64, 101, 101, 3]

# 进行最大池化
y1 = pool1(x)
print(y1.shape) # [64, 51, 51, 3]

# 进行最大池化
y2 = pool2(x)
print(y2.shape) # [64, 50, 50, 3]