292 lines
11 KiB
Python
292 lines
11 KiB
Python
|
# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
|
||
|
#
|
||
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
# you may not use this file except in compliance with the License.
|
||
|
# You may obtain a copy of the License at
|
||
|
#
|
||
|
# http://www.apache.org/licenses/LICENSE-2.0
|
||
|
#
|
||
|
# Unless required by applicable law or agreed to in writing, software
|
||
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
# See the License for the specific language governing permissions and
|
||
|
# limitations under the License.
|
||
|
# ==============================================================================
|
||
|
"""Python wrappers for reader Datasets."""
|
||
|
from __future__ import absolute_import
|
||
|
from __future__ import division
|
||
|
from __future__ import print_function
|
||
|
|
||
|
from tensorflow.python.data.ops import dataset_ops
|
||
|
from tensorflow.python.data.util import convert
|
||
|
from tensorflow.python.framework import dtypes
|
||
|
from tensorflow.python.framework import ops
|
||
|
from tensorflow.python.framework import tensor_shape
|
||
|
from tensorflow.python.ops import array_ops
|
||
|
from tensorflow.python.ops import gen_dataset_ops
|
||
|
from tensorflow.python.util.tf_export import tf_export
|
||
|
|
||
|
|
||
|
# TODO(b/64974358): Increase default buffer size to 256 MB.
|
||
|
_DEFAULT_READER_BUFFER_SIZE_BYTES = 256 * 1024 # 256 KB
|
||
|
|
||
|
|
||
|
@tf_export("data.TextLineDataset")
|
||
|
class TextLineDataset(dataset_ops.Dataset):
|
||
|
"""A `Dataset` comprising lines from one or more text files."""
|
||
|
|
||
|
def __init__(self, filenames, compression_type=None, buffer_size=None):
|
||
|
"""Creates a `TextLineDataset`.
|
||
|
|
||
|
Args:
|
||
|
filenames: A `tf.string` tensor containing one or more filenames.
|
||
|
compression_type: (Optional.) A `tf.string` scalar evaluating to one of
|
||
|
`""` (no compression), `"ZLIB"`, or `"GZIP"`.
|
||
|
buffer_size: (Optional.) A `tf.int64` scalar denoting the number of bytes
|
||
|
to buffer. A value of 0 results in the default buffering values chosen
|
||
|
based on the compression type.
|
||
|
"""
|
||
|
super(TextLineDataset, self).__init__()
|
||
|
self._filenames = ops.convert_to_tensor(
|
||
|
filenames, dtype=dtypes.string, name="filenames")
|
||
|
self._compression_type = convert.optional_param_to_tensor(
|
||
|
"compression_type",
|
||
|
compression_type,
|
||
|
argument_default="",
|
||
|
argument_dtype=dtypes.string)
|
||
|
self._buffer_size = convert.optional_param_to_tensor(
|
||
|
"buffer_size", buffer_size, _DEFAULT_READER_BUFFER_SIZE_BYTES)
|
||
|
|
||
|
def _as_variant_tensor(self):
|
||
|
return gen_dataset_ops.text_line_dataset(
|
||
|
self._filenames, self._compression_type, self._buffer_size)
|
||
|
|
||
|
@property
|
||
|
def output_classes(self):
|
||
|
return ops.Tensor
|
||
|
|
||
|
@property
|
||
|
def output_shapes(self):
|
||
|
return tensor_shape.scalar()
|
||
|
|
||
|
@property
|
||
|
def output_types(self):
|
||
|
return dtypes.string
|
||
|
|
||
|
|
||
|
class _TFRecordDataset(dataset_ops.Dataset):
|
||
|
"""A `Dataset` comprising records from one or more TFRecord files."""
|
||
|
|
||
|
def __init__(self, filenames, compression_type=None, buffer_size=None):
|
||
|
"""Creates a `TFRecordDataset`.
|
||
|
|
||
|
Args:
|
||
|
filenames: A `tf.string` tensor containing one or more filenames.
|
||
|
compression_type: (Optional.) A `tf.string` scalar evaluating to one of
|
||
|
`""` (no compression), `"ZLIB"`, or `"GZIP"`.
|
||
|
buffer_size: (Optional.) A `tf.int64` scalar representing the number of
|
||
|
bytes in the read buffer. 0 means no buffering.
|
||
|
"""
|
||
|
super(_TFRecordDataset, self).__init__()
|
||
|
# Force the type to string even if filenames is an empty list.
|
||
|
self._filenames = ops.convert_to_tensor(
|
||
|
filenames, dtypes.string, name="filenames")
|
||
|
self._compression_type = convert.optional_param_to_tensor(
|
||
|
"compression_type",
|
||
|
compression_type,
|
||
|
argument_default="",
|
||
|
argument_dtype=dtypes.string)
|
||
|
self._buffer_size = convert.optional_param_to_tensor(
|
||
|
"buffer_size",
|
||
|
buffer_size,
|
||
|
argument_default=_DEFAULT_READER_BUFFER_SIZE_BYTES)
|
||
|
|
||
|
def _as_variant_tensor(self):
|
||
|
return gen_dataset_ops.tf_record_dataset(
|
||
|
self._filenames, self._compression_type, self._buffer_size)
|
||
|
|
||
|
@property
|
||
|
def output_classes(self):
|
||
|
return ops.Tensor
|
||
|
|
||
|
@property
|
||
|
def output_shapes(self):
|
||
|
return tensor_shape.TensorShape([])
|
||
|
|
||
|
@property
|
||
|
def output_types(self):
|
||
|
return dtypes.string
|
||
|
|
||
|
|
||
|
class ParallelInterleaveDataset(dataset_ops.InterleaveDataset):
|
||
|
"""A `Dataset` that maps a function over its input and flattens the result."""
|
||
|
|
||
|
def __init__(self, input_dataset, map_func, cycle_length, block_length,
|
||
|
sloppy, buffer_output_elements, prefetch_input_elements):
|
||
|
"""See `tf.contrib.data.parallel_interleave()` for details."""
|
||
|
super(ParallelInterleaveDataset, self).__init__(input_dataset, map_func,
|
||
|
cycle_length, block_length)
|
||
|
self._sloppy = ops.convert_to_tensor(
|
||
|
sloppy, dtype=dtypes.bool, name="sloppy")
|
||
|
self._buffer_output_elements = convert.optional_param_to_tensor(
|
||
|
"buffer_output_elements",
|
||
|
buffer_output_elements,
|
||
|
argument_default=2 * block_length)
|
||
|
self._prefetch_input_elements = convert.optional_param_to_tensor(
|
||
|
"prefetch_input_elements",
|
||
|
prefetch_input_elements,
|
||
|
argument_default=2 * cycle_length)
|
||
|
|
||
|
def _as_variant_tensor(self):
|
||
|
# pylint: disable=protected-access
|
||
|
return gen_dataset_ops.parallel_interleave_dataset(
|
||
|
self._input_dataset._as_variant_tensor(),
|
||
|
self._map_func.captured_inputs,
|
||
|
self._cycle_length,
|
||
|
self._block_length,
|
||
|
self._sloppy,
|
||
|
self._buffer_output_elements,
|
||
|
self._prefetch_input_elements,
|
||
|
f=self._map_func,
|
||
|
**dataset_ops.flat_structure(self))
|
||
|
# pylint: enable=protected-access
|
||
|
|
||
|
def _transformation_name(self):
|
||
|
return "tf.contrib.data.parallel_interleave()"
|
||
|
|
||
|
|
||
|
@tf_export("data.TFRecordDataset")
|
||
|
class TFRecordDataset(dataset_ops.Dataset):
|
||
|
"""A `Dataset` comprising records from one or more TFRecord files."""
|
||
|
|
||
|
def __init__(self, filenames, compression_type=None, buffer_size=None,
|
||
|
num_parallel_reads=None):
|
||
|
"""Creates a `TFRecordDataset` to read for one or more TFRecord files.
|
||
|
|
||
|
NOTE: The `num_parallel_reads` argument can be used to improve performance
|
||
|
when reading from a remote filesystem.
|
||
|
|
||
|
Args:
|
||
|
filenames: A `tf.string` tensor or `tf.data.Dataset` containing one or
|
||
|
more filenames.
|
||
|
compression_type: (Optional.) A `tf.string` scalar evaluating to one of
|
||
|
`""` (no compression), `"ZLIB"`, or `"GZIP"`.
|
||
|
buffer_size: (Optional.) A `tf.int64` scalar representing the number of
|
||
|
bytes in the read buffer. 0 means no buffering.
|
||
|
num_parallel_reads: (Optional.) A `tf.int64` scalar representing the
|
||
|
number of files to read in parallel. Defaults to reading files
|
||
|
sequentially.
|
||
|
|
||
|
Raises:
|
||
|
TypeError: If any argument does not have the expected type.
|
||
|
ValueError: If any argument does not have the expected shape.
|
||
|
"""
|
||
|
super(TFRecordDataset, self).__init__()
|
||
|
if isinstance(filenames, dataset_ops.Dataset):
|
||
|
if filenames.output_types != dtypes.string:
|
||
|
raise TypeError(
|
||
|
"`filenames` must be a `tf.data.Dataset` of `tf.string` elements.")
|
||
|
if not filenames.output_shapes.is_compatible_with(tensor_shape.scalar()):
|
||
|
raise ValueError(
|
||
|
"`filenames` must be a `tf.data.Dataset` of scalar `tf.string` "
|
||
|
"elements.")
|
||
|
else:
|
||
|
filenames = ops.convert_to_tensor(filenames, dtype=dtypes.string)
|
||
|
filenames = array_ops.reshape(filenames, [-1], name="flat_filenames")
|
||
|
filenames = dataset_ops.Dataset.from_tensor_slices(filenames)
|
||
|
|
||
|
self._filenames = filenames
|
||
|
self._compression_type = compression_type
|
||
|
self._buffer_size = buffer_size
|
||
|
self._num_parallel_reads = num_parallel_reads
|
||
|
|
||
|
def read_one_file(filename):
|
||
|
return _TFRecordDataset(filename, compression_type, buffer_size)
|
||
|
|
||
|
if num_parallel_reads is None:
|
||
|
self._impl = filenames.flat_map(read_one_file)
|
||
|
else:
|
||
|
self._impl = ParallelInterleaveDataset(
|
||
|
filenames, read_one_file, cycle_length=num_parallel_reads,
|
||
|
block_length=1, sloppy=False, buffer_output_elements=None,
|
||
|
prefetch_input_elements=None)
|
||
|
|
||
|
def _clone(self,
|
||
|
filenames=None,
|
||
|
compression_type=None,
|
||
|
buffer_size=None,
|
||
|
num_parallel_reads=None):
|
||
|
return TFRecordDataset(filenames or self._filenames,
|
||
|
compression_type or self._compression_type,
|
||
|
buffer_size or self._buffer_size,
|
||
|
num_parallel_reads or self._num_parallel_reads)
|
||
|
|
||
|
def _as_variant_tensor(self):
|
||
|
return self._impl._as_variant_tensor() # pylint: disable=protected-access
|
||
|
|
||
|
@property
|
||
|
def output_classes(self):
|
||
|
return self._impl.output_classes
|
||
|
|
||
|
@property
|
||
|
def output_shapes(self):
|
||
|
return self._impl.output_shapes
|
||
|
|
||
|
@property
|
||
|
def output_types(self):
|
||
|
return self._impl.output_types
|
||
|
|
||
|
|
||
|
@tf_export("data.FixedLengthRecordDataset")
|
||
|
class FixedLengthRecordDataset(dataset_ops.Dataset):
|
||
|
"""A `Dataset` of fixed-length records from one or more binary files."""
|
||
|
|
||
|
def __init__(self,
|
||
|
filenames,
|
||
|
record_bytes,
|
||
|
header_bytes=None,
|
||
|
footer_bytes=None,
|
||
|
buffer_size=None):
|
||
|
"""Creates a `FixedLengthRecordDataset`.
|
||
|
|
||
|
Args:
|
||
|
filenames: A `tf.string` tensor containing one or more filenames.
|
||
|
record_bytes: A `tf.int64` scalar representing the number of bytes in
|
||
|
each record.
|
||
|
header_bytes: (Optional.) A `tf.int64` scalar representing the number of
|
||
|
bytes to skip at the start of a file.
|
||
|
footer_bytes: (Optional.) A `tf.int64` scalar representing the number of
|
||
|
bytes to ignore at the end of a file.
|
||
|
buffer_size: (Optional.) A `tf.int64` scalar representing the number of
|
||
|
bytes to buffer when reading.
|
||
|
"""
|
||
|
super(FixedLengthRecordDataset, self).__init__()
|
||
|
self._filenames = ops.convert_to_tensor(
|
||
|
filenames, dtype=dtypes.string, name="filenames")
|
||
|
self._record_bytes = ops.convert_to_tensor(
|
||
|
record_bytes, dtype=dtypes.int64, name="record_bytes")
|
||
|
|
||
|
self._header_bytes = convert.optional_param_to_tensor(
|
||
|
"header_bytes", header_bytes)
|
||
|
self._footer_bytes = convert.optional_param_to_tensor(
|
||
|
"footer_bytes", footer_bytes)
|
||
|
self._buffer_size = convert.optional_param_to_tensor(
|
||
|
"buffer_size", buffer_size, _DEFAULT_READER_BUFFER_SIZE_BYTES)
|
||
|
|
||
|
def _as_variant_tensor(self):
|
||
|
return gen_dataset_ops.fixed_length_record_dataset(
|
||
|
self._filenames, self._header_bytes, self._record_bytes,
|
||
|
self._footer_bytes, self._buffer_size)
|
||
|
|
||
|
@property
|
||
|
def output_classes(self):
|
||
|
return ops.Tensor
|
||
|
|
||
|
@property
|
||
|
def output_shapes(self):
|
||
|
return tensor_shape.scalar()
|
||
|
|
||
|
@property
|
||
|
def output_types(self):
|
||
|
return dtypes.string
|