Python tensorflow keras加载json模型出错：无法找到类'Sequential

Question

我几周前建立并训练了我的模型，并把它保存在了model.json和model.h5这两个文件里。

今天，当我尝试用model_from_json来加载它时，出现了一个错误。

TypeError: Could not locate class 'Sequential'. Make sure custom classes are decorated with `@keras.saving.register_keras_serializable()`. Full object config: {'class_name': 'Sequential', 'config': {'name': 'sequential_7', 'layers': [{'module': 'keras.layers', 'class_name': 'InputLayer', 'config': {'batch_input_shape': [None, 244, 244, 3], 'dtype': 'float32', 'sparse': False, 'ragged': False, 'name': 'conv2d_15_input'}, 'registered_name': None}, {'module': 'keras.layers', 'class_name': 'Conv2D', 'config': {'name': 'conv2d_15', 'trainable': True, 'dtype': 'float32', 'batch_input_shape': [None, 244, 244, 3], 'filters': 32, 'kernel_size': [3, 3], 'strides': [1, 1], 'padding': 'valid', 'data_format': 'channels_last', 'dilation_rate': [1, 1], 'groups': 1, 'activation': 'relu', 'use_bias': True, 'kernel_initializer': {'module': 'keras.initializers', 'class_name': 'GlorotUniform', 'config': {'seed': None}, 'registered_name': None}, 'bias_initializer': {'module': 'keras.initializers', 'class_name': 'Zeros', 'config': {}, 'registered_name': None}, 'kernel_regularizer': None, 'bias_regularizer': None, 'activity_regularizer': None, 'kernel_constraint': None, 'bias_constraint': None}, 'registered_name': None, 'build_config': {'input_shape': [None, 244, 244, 3]}}, {'module': 'keras.layers', 'class_name': 'MaxPooling2D', 'config': {'name': 'max_pooling2d_14', 'trainable': True, 'dtype': 'float32', 'pool_size': [2, 2], 'padding': 'valid', 'strides': [2, 2], 'data_format': 'channels_last'}, 'registered_name': None, 'build_config': {'input_shape': [None, 242, 242, 32]}}, {'module': 'keras.layers', 'class_name': 'Conv2D', 'config': {'name': 'conv2d_16', 'trainable': True, 'dtype': 'float32', 'filters': 64, 'kernel_size': [3, 3], 'strides': [1, 1], 'padding': 'valid', 'data_format': 'channels_last', 'dilation_rate': [1, 1], 'groups': 1, 'activation': 'relu', 'use_bias': True, 'kernel_initializer': {'module': 'keras.initializers', 'class_name': 'GlorotUniform', 'config': {'seed': None}, 'registered_name': None}, 'bias_initializer': {'module': 'keras.initializers', 'class_name': 'Zeros', 'config': {}, 'registered_name': None}, 'kernel_regularizer': None, 'bias_regularizer': None, 'activity_regularizer': None, 'kernel_constraint': None, 'bias_constraint': None}, 'registered_name': None, 'build_config': {'input_shape': [None, 121, 121, 32]}}, {'module': 'keras.layers', 'class_name': 'MaxPooling2D', 'config': {'name': 'max_pooling2d_15', 'trainable': True, 'dtype': 'float32', 'pool_size': [2, 2], 'padding': 'valid', 'strides': [2, 2], 'data_format': 'channels_last'}, 'registered_name': None, 'build_config': {'input_shape': [None, 119, 119, 64]}}, {'module': 'keras.layers', 'class_name': 'Flatten', 'config': {'name': 'flatten_7', 'trainable': True, 'dtype': 'float32', 'data_format': 'channels_last'}, 'registered_name': None, 'build_config': {'input_shape': [None, 59, 59, 64]}}, {'module': 'keras.layers', 'class_name': 'Dense', 'config': {'name': 'dense_14', 'trainable': True, 'dtype': 'float32', 'units': 64, 'activation': 'relu', 'use_bias': True, 'kernel_initializer': {'module': 'keras.initializers', 'class_name': 'GlorotUniform', 'config': {'seed': None}, 'registered_name': None}, 'bias_initializer': {'module': 'keras.initializers', 'class_name': 'Zeros', 'config': {}, 'registered_name': None}, 'kernel_regularizer': None, 'bias_regularizer': None, 'activity_regularizer': None, 'kernel_constraint': None, 'bias_constraint': None}, 'registered_name': None, 'build_config': {'input_shape': [None, 222784]}}, {'module': 'keras.layers', 'class_name': 'Dense', 'config': {'name': 'dense_15', 'trainable': True, 'dtype': 'float32', 'units': 2, 'activation': 'softmax', 'use_bias': True, 'kernel_initializer': {'module': 'keras.initializers', 'class_name': 'GlorotUniform', 'config': {'seed': None}, 'registered_name': None}, 'bias_initializer': {'module': 'keras.initializers', 'class_name': 'Zeros', 'config': {}, 'registered_name': None}, 'kernel_regularizer': None, 'bias_regularizer': None, 'activity_regularizer': None, 'kernel_constraint': None, 'bias_constraint': None}, 'registered_name': None, 'build_config': {'input_shape': [None, 64]}}]}, 'keras_version': '2.13.1', 'backend': 'tensorflow'}

我已经导入了所有需要的库：

import numpy as np
from keras.preprocessing import image
from keras.models import model_from_json

from tensorflow.keras import layers
from tensorflow.keras.preprocessing.image import ImageDataGenerator, load_img, img_to_array
from tensorflow.keras.models import Sequential, Model
from tensorflow.keras.layers import Conv2D, MaxPooling2D, Dense, GlobalAveragePooling2D, Dropout, Flatten
from tensorflow.keras.applications import VGG16

这是我用来加载保存的json模型的代码：

json_file = open('./model/model.json', 'r')
loaded_model_json = json_file.read()
json_file.close()
loaded_model = model_from_json(loaded_model_json)
loaded_model.load_weights("model.h5")

我是不是漏掉了什么？

Answer 1

因为@kartoos的评论，我检查了一下版本。是的，我在Kaggle上的笔记本使用的是tensorflow 2.13.1版本，而我现在想加载的是2.16.1版本的tensorflow。

我尝试安装2.13.1版本，但找不到方法，所以我决定用2.16.1版本的tensorflow重新构建和训练我的模型，这样做成功了，没有再出现错误，模型在保存和重新加载时也能正常工作。

我把模型保存为keras格式，而不是json格式。

model.save('model.keras')

然后再加载模型。

loaded_model = keras.models.load_model("./model/model.keras")

谢谢！