1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
# Copyright 2015 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.
# ==============================================================================
"""For reading and writing TFRecords files."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from tensorflow.python import pywrap_tensorflow
from tensorflow.python.util import compat
class TFRecordCompressionType(object):
NONE = 0
ZLIB = 1
GZIP = 2
# NOTE(vrv): This will eventually be converted into a proto. to match
# the interface used by the C++ RecordWriter.
class TFRecordOptions(object):
def __init__(self, compression_type):
self.compression_type = compression_type
def get_type_as_string(self):
if self.compression_type == TFRecordCompressionType.ZLIB:
return "ZLIB"
elif self.compression_type == TFRecordCompressionType.GZIP:
return "GZIP"
else:
return ""
def tf_record_iterator(path, options=None):
"""An iterator that read the records from a TFRecords file.
Args:
path: The path to the TFRecords file.
options: (optional) A TFRecordOptions object.
Yields:
Strings.
Raises:
IOError: If `path` cannot be opened for reading.
"""
compression_type_string = options.get_type_as_string() if options else ""
reader = pywrap_tensorflow.PyRecordReader_New(
compat.as_bytes(path), 0, compat.as_bytes(compression_type_string))
if reader is None:
raise IOError("Could not open %s." % path)
while reader.GetNext():
yield reader.record()
reader.Close()
class TFRecordWriter(object):
"""A class to write records to a TFRecords file.
This class implements `__enter__` and `__exit__`, and can be used
in `with` blocks like a normal file.
@@__init__
@@write
@@close
"""
# TODO(josh11b): Support appending?
def __init__(self, path, options=None):
"""Opens file `path` and creates a `TFRecordWriter` writing to it.
Args:
path: The path to the TFRecords file.
options: (optional) A TFRecordOptions object.
Raises:
IOError: If `path` cannot be opened for writing.
"""
compression_type_string = options.get_type_as_string() if options else ""
self._writer = pywrap_tensorflow.PyRecordWriter_New(
compat.as_bytes(path), compat.as_bytes(compression_type_string))
if self._writer is None:
raise IOError("Could not write to %s." % path)
def __enter__(self):
"""Enter a `with` block."""
return self
def __exit__(self, unused_type, unused_value, unused_traceback):
"""Exit a `with` block, closing the file."""
self.close()
def write(self, record):
"""Write a string record to the file.
Args:
record: str
"""
self._writer.WriteRecord(record)
def close(self):
"""Close the file."""
self._writer.Close()
|
