在Keras的自动编码器的最后一层中裁剪

Question

我有形状391 x 400的图像。我试图使用此处所述使用自动编码器。

具体来说，我使用了以下代码：

from keras.layers import Input, Dense, Conv2D, MaxPooling2D, UpSampling2D
from keras.models import Model
from keras import backend as K
input_img = Input(shape=(391, 400, 1))  # adapt this if using `channels_first` image data format
x = Conv2D(16, (3, 3), activation='relu', padding='same')(input_img)
x = MaxPooling2D((2, 2), padding='same')(x)
x = Conv2D(8, (3, 3), activation='relu', padding='same')(x)
x = MaxPooling2D((2, 2), padding='same')(x)
x = Conv2D(8, (3, 3), activation='relu', padding='same')(x)
encoded = MaxPooling2D((2, 2), padding='same')(x)
# at this point the representation is (4, 4, 8) i.e. 128-dimensional
x = Conv2D(8, (3, 3), activation='relu', padding='same')(encoded)
x = UpSampling2D((2, 2))(x)
x = Conv2D(8, (3, 3), activation='relu', padding='same')(x)
x = UpSampling2D((2, 2))(x)
x = Conv2D(16, (3, 3), activation='relu', padding='same')(x)
x = UpSampling2D((2, 2))(x)
decoded = Conv2D(1, (3, 3), activation='sigmoid', padding='same')(x)
autoencoder = Model(input_img, decoded)
autoencoder.compile(optimizer='adadelta', loss='binary_crossentropy')

我得到以下内容：

ValueError: Error when checking target: expected conv2d_37 to have shape (None, 392, 400, 1) but got array with shape (500, 391, 400, 1)

我需要的是：将掉落/裁剪/重塑最后一层从 392 x 400到 391 x 400。

感谢您的任何帮助。

Answer 1

有一个称为 Cropping2D的图层。要裁剪从392 x 400到391 x 400的最后一层，您可以使用它：

cropped = Cropping2D(cropping=((1, 0), (0, 0)))(decoded)
autoencoder = Model(input_img, cropped)

元组((1, 0), (0, 0))意味着从顶部裁剪1行。如果要从底部裁剪，请改用((0, 1), (0, 0))。您可以看到文档以获取有关cropping参数的更详细说明。