我正在尝试keras.util.Sequence
用我的班级覆盖SequenceGenerator(Sequence)
并将其传递给fit_generator
,但fit_generator
引发了错误ValueError
这是我的自定义类
import os import numpy as np from keras.utils import Sequence from batchGenerator import BatchGenerator
从设置导入 batch_size、train_folder、test_folder
class SequenceGenerator(Sequence):
def __init__(self, batches_folder):
self.batch_generator = BatchGenerator(folder_name=batches_folder)
self.names = [f for f in os.listdir(batches_folder) if f.lower().endswith('.jpg')]
def __len__(self):
return int(np.ceil(len(self.names) / float(batch_size)))
def __getitem__(self, idx):
print('Getting a bacth{0}'.format(idx))
[X_batch, Y_batch] = self.batch_generator.load_batch_from_disk(idx)
return X_batch, Y_batch
def train_seq_genenrator():
return SequenceGenerator(train_folder)
def test_seq_generator():
return SequenceGenerator(test_folder)
在 jupyter notebook 中,我导入了以下内容
from sequenceGenerator import train_seq_genenrator, test_seq_generator
最后,你是 fit_generator 调用
history = new_model.fit_generator(train_seq_genenrator()
, steps_per_epoch=num_train_samples // batch_size
, validation_data=test_seq_generator()
, validation_steps=num_test_samples // batch_size
, epochs=epochs
, shuffle=True)
我收到以下错误:
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-63-347bef86c8c0> in <module>()
4 , validation_steps=num_test_samples // batch_size
5 , epochs=epochs
----> 6 , shuffle=True)
~\Anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training.py in fit_generator(self, generator, steps_per_epoch, epochs, verbose, callbacks, validation_data, validation_steps, class_weight, max_queue_size, workers, use_multiprocessing, shuffle, initial_epoch)
1759 use_multiprocessing=use_multiprocessing,
1760 shuffle=shuffle,
-> 1761 initial_epoch=initial_epoch)
1762
1763 def evaluate_generator(self,
~\Anaconda3\envs\tensorflow\lib\site-packages\tensorflow\python\keras\engine\training_generator.py in fit_generator(model, generator, steps_per_epoch, epochs, verbose, callbacks, validation_data, validation_steps, class_weight, max_queue_size, workers, use_multiprocessing, shuffle, initial_epoch)
121 '`validation_data` should be a tuple '
122 '`(val_x, val_y, val_sample_weight)` '
--> 123 'or `(val_x, val_y)`. Found: ' + str(validation_data))
124 val_x, val_y, val_sample_weights = model._standardize_user_data(
125 val_x, val_y, val_sample_weight)
ValueError: `validation_data` should be a tuple `(val_x, val_y, val_sample_weight)` or `(val_x, val_y)`. Found: <sequenceGenerator.SequenceGenerator object at 0x000001DCB58259B0>
我不知道为什么会这样,但是在https://keras.io/models/sequential/
validation_data:这可以是
- 验证数据的生成器或序列对象
- 元组 (x_val, y_val)
- 元组 (x_val, y_val, val_sample_weights)