我正在尝试在 Keras 中实现非池化掩码。我有一个 VGG 编码器,可以输出特定的特征图(例如 relu5_1)和反池化掩码列表。
def VGG19(input_tensor=None, input_shape=None, target_layer=1):
"""
VGG19, up to the target layer (1 for relu1_1, 2 for relu2_1, etc.)
"""
if input_tensor is None:
inputs = Input(shape=input_shape)
else:
inputs = Input(tensor=input_tensor, shape=input_shape)
layer, unpooling_masks = vgg_layers(inputs, target_layer)
model = Model(inputs, [layer, unpooling_masks], name='vgg19')
load_weights(model)
return model, unpooling_masks
def vgg_layers(inputs, target_layer):
unpooling_masks = []
# Block 1
x_b1 = Conv2D(64, (3, 3), activation='relu', padding='same', name='block1_conv1')(inputs)
x = Conv2D(64, (3, 3), activation='relu', padding='same', name='block1_conv2')(x_b1)
before_pooling = x
x = MaxPooling2D((2, 2), strides=(2, 2), name='block1_pool')(x)
unpooling_masks.append(make_unpooling_mask(x, before_pooling))
# Block 2
x_b2 = Conv2D(128, (3, 3), activation='relu', padding='same', name='block2_conv1')(x)
x = Conv2D(128, (3, 3), activation='relu', padding='same', name='block2_conv2')(x_b2)
before_pooling = x
x = MaxPooling2D((2, 2), strides=(2, 2), name='block2_pool')(x)
unpooling_masks.append(make_unpooling_mask(x, before_pooling))
# Block 3
x_b3 = Conv2D(256, (3, 3), activation='relu', padding='same', name='block3_conv1')(x)
x = Conv2D(256, (3, 3), activation='relu', padding='same', name='block3_conv2')(x_b3)
x = Conv2D(256, (3, 3), activation='relu', padding='same', name='block3_conv3')(x)
x = Conv2D(256, (3, 3), activation='relu', padding='same', name='block3_conv4')(x)
before_pooling = x
x = MaxPooling2D((2, 2), strides=(2, 2), name='block3_pool')(x)
unpooling_masks.append(make_unpooling_mask(x, before_pooling))
# Block 4
x_b4 = Conv2D(512, (3, 3), activation='relu', padding='same', name='block4_conv1')(x)
x = Conv2D(512, (3, 3), activation='relu', padding='same', name='block4_conv2')(x_b4)
x = Conv2D(512, (3, 3), activation='relu', padding='same', name='block4_conv3')(x)
x = Conv2D(512, (3, 3), activation='relu', padding='same', name='block4_conv4')(x)
before_pooling = x
x = MaxPooling2D((2, 2), strides=(2, 2), name='block4_pool')(x)
unpooling_masks.append(make_unpooling_mask(x, before_pooling))
# Block 5
x_b5 = Conv2D(512, (3, 3), activation='relu', padding='same', name='block5_conv1')(x)
if target_layer == 5:
return x_b5, unpooling_masks
elif target_layer == 4:
return x_b4, unpooling_masks
elif target_layer == 3:
return x_b3, unpooling_masks
elif target_layer == 2:
return x_b2, unpooling_masks
elif target_layer == 1:
return x_b1, unpooling_masks
这是unpooling函数
def make_unpooling_mask(x, before_pooling):
t = UpSampling2D()(x)
mask = Lambda(lambda x: K.cast(K.greater(x[0],x[1]), dtype='float32'))([t, before_pooling])
return mask
我收到此错误
Exception has occurred: ValueError Output tensors to a Model must be the output of a Keras
Layer
(thus holding past layer metadata).Found: [<tf.Tensor 'lambda_1/Cast:0' shape=(?, 256, 256, 64) dtype=float32>, <tf.Tensor 'lambda_2/Cast:0' shape=(?, 128, 128, 128) dtype=float32>, <tf.Tensor 'lambda_3/Cast:0' shape=(?, 64, 64, 256) dtype=float32>, <tf.Tensor 'lambda_4/Cast:0' shape=(?, 32, 32, 512) dtype=float32>]
在编译模型的行 model = Model(inputs, [layer, unpooling_masks], name='vgg19')
时会发生这种情况
可以做什么?
最佳答案
调用模型 API 时,输出参数的值应该是张量(或张量列表),在本例中它是张量列表的列表,因此存在问题。只需在调用 Model 时解压 unpooling_masks 列表(*unpooling_masks)即可。
model = Model(inputs, [layer, *unpooling_masks], name='vgg19')
关于python - Keras 模型的输出张量必须是 Keras `Layer` 的输出(因此保存过去层元数据),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/55133051/