Keras 3 API 文档 / 层 API / 特定于后端的层 / TorchModuleWrapper 层

TorchModuleWrapper 层

[source]

TorchModuleWrapper class

keras.layers.TorchModuleWrapper(module, name=None, **kwargs)

Torch 模块包装层.

TorchModuleWrapper 是一个包装类,可以将任何 torch.nn.Module 转换为 Keras 层,特别是通过使其参数可被 Keras 跟踪.

TorchModuleWrapper 仅兼容 PyTorch 后端,不能与 TensorFlow 或 JAX 后端一起使用.

参数: module: torch.nn.Module 实例.如果它是 LazyModule 实例,则必须在将其传递给 TorchModuleWrapper 之前初始化其参数(例如,通过调用一次). name: 层的名称(字符串).

示例:

以下是如何将 TorchModuleWrapper 与普通 PyTorch 模块一起使用的示例.

import torch.nn as nn
import torch.nn.functional as F

import keras
from keras.src.layers import TorchModuleWrapper

class Classifier(keras.Model):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        # 如果包含参数,使用 `TorchModuleWrapper` 包装 `torch.nn.Module`
        self.conv1 = TorchModuleWrapper(
            nn.Conv2d(in_channels=1, out_channels=32, kernel_size=(3, 3))
        )
        self.conv2 = TorchModuleWrapper(
            nn.Conv2d(in_channels=32, out_channels=64, kernel_size=(3, 3))
        )
        self.pool = nn.MaxPool2d(kernel_size=(2, 2))
        self.flatten = nn.Flatten()
        self.dropout = nn.Dropout(p=0.5)
        self.fc = TorchModuleWrapper(nn.Linear(1600, 10))

    def call(self, inputs):
        x = F.relu(self.conv1(inputs))
        x = self.pool(x)
        x = F.relu(self.conv2(x))
        x = self.pool(x)
        x = self.flatten(x)
        x = self.dropout(x)
        x = self.fc(x)
        return F.softmax(x, dim=1)


model = Classifier()
model.build((1, 28, 28))
print("# Output shape", model(torch.ones(1, 1, 28, 28).to("cuda")).shape)

model.compile(
    loss="sparse_categorical_crossentropy",
    optimizer="adam",
    metrics=["accuracy"]
)
model.fit(train_loader, epochs=5)