def mnist_input_fn(params):
dataset, num_examples = mnist.load_mnist_as_dataset(flatten_images=True)
# Shuffle before repeat is correct unless you want repeat cases in the
# same batch.
dataset = (dataset.shuffle(num_examples).repeat().batch(
params['batch_size'],
drop_remainder=True).prefetch(tf.data.experimental.AUTOTUNE))
return dataset
def load_mnist():
"""Creates MNIST dataset and wraps it inside cached data reader.
Returns:
cached_reader: `data_reader.CachedReader` instance which wraps MNIST
dataset.
num_examples: int. The number of training examples.
"""
# Wrap the data set into cached_reader which provides variable sized training
# and caches the read train batch.
if not FLAGS.use_alt_data_reader:
# Version 1 using data_reader.py (slow!)
dataset, num_examples = mnist.load_mnist_as_dataset(
flatten_images=False)
if FLAGS.use_batch_size_schedule:
max_batch_size = num_examples
else:
max_batch_size = FLAGS.batch_size
# Shuffle before repeat is correct unless you want repeat cases in the
# same batch.
dataset = (dataset.shuffle(num_examples).repeat().batch(
max_batch_size).prefetch(5))
dataset = tf.compat.v1.data.make_one_shot_iterator(dataset).get_next()
# This version of CachedDataReader requires the dataset to be shuffled
return data_reader.CachedDataReader(dataset,
max_batch_size), num_examples
else:
# Version 2 using data_reader_alt.py (faster)
images, labels, num_examples = mnist.load_mnist_as_tensors(
flatten_images=False)
dataset = (images, labels)
# This version of CachedDataReader requires the dataset to NOT be shuffled
return data_reader_alt.CachedDataReader(dataset,
num_examples), num_examples