Fix the ImageDataGenerator methods to return Keras sequences instead of just generators. This makes it so that Keras fit avoids an infinite loop when users pass the results of ImageDataGenerator.flow* directly to fit/evaluate/predict.

PiperOrigin-RevId: 311028701
Change-Id: Ia5c3b01b3c8fa6b842bddb881ced64e4b89fe2ba
This commit is contained in:
Tomer Kaftan 2020-05-11 17:30:14 -07:00 committed by TensorFlower Gardener
parent 22a24beeee
commit b53ed4d560
3 changed files with 427 additions and 1 deletions

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@ -85,6 +85,7 @@ tf_py_test(
deps = [
":image",
"//tensorflow/python:client_testlib",
"//tensorflow/python/keras",
"//third_party/py/numpy",
],
)

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@ -14,6 +14,7 @@
# ==============================================================================
# pylint: disable=invalid-name
# pylint: disable=g-import-not-at-top
# pylint: disable=g-classes-have-attributes
"""Set of tools for real-time data augmentation on image data.
"""
from __future__ import absolute_import
@ -35,6 +36,7 @@ from tensorflow.python.keras.utils import data_utils
from tensorflow.python.ops import array_ops
from tensorflow.python.ops import image_ops
from tensorflow.python.ops import math_ops
from tensorflow.python.platform import tf_logging
from tensorflow.python.util import tf_inspect
from tensorflow.python.util.tf_export import keras_export
@ -459,6 +461,123 @@ class NumpyArrayIterator(image.NumpyArrayIterator, Iterator):
**kwargs)
class DataFrameIterator(image.DataFrameIterator, Iterator):
"""Iterator capable of reading images from a directory on disk as a dataframe.
Arguments:
dataframe: Pandas dataframe containing the filepaths relative to
`directory` (or absolute paths if `directory` is None) of the images in
a string column. It should include other column/s
depending on the `class_mode`: - if `class_mode` is `"categorical"`
(default value) it must include the `y_col` column with the class/es
of each image. Values in column can be string/list/tuple if a single
class or list/tuple if multiple classes. - if `class_mode` is
`"binary"` or `"sparse"` it must include the given `y_col` column
with class values as strings. - if `class_mode` is `"raw"` or
`"multi_output"` it should contain the columns specified in `y_col`.
- if `class_mode` is `"input"` or `None` no extra column is needed.
directory: string, path to the directory to read images from. If `None`,
data in `x_col` column should be absolute paths.
image_data_generator: Instance of `ImageDataGenerator` to use for random
transformations and normalization. If None, no transformations and
normalizations are made.
x_col: string, column in `dataframe` that contains the filenames (or
absolute paths if `directory` is `None`).
y_col: string or list, column/s in `dataframe` that has the target data.
weight_col: string, column in `dataframe` that contains the sample
weights. Default: `None`.
target_size: tuple of integers, dimensions to resize input images to.
color_mode: One of `"rgb"`, `"rgba"`, `"grayscale"`. Color mode to read
images.
classes: Optional list of strings, classes to use (e.g. `["dogs",
"cats"]`). If None, all classes in `y_col` will be used.
class_mode: one of "binary", "categorical", "input", "multi_output",
"raw", "sparse" or None. Default: "categorical".
Mode for yielding the targets:
- `"binary"`: 1D numpy array of binary labels,
- `"categorical"`: 2D numpy array of one-hot encoded labels. Supports
multi-label output.
- `"input"`: images identical to input images (mainly used to work
with autoencoders),
- `"multi_output"`: list with the values of the different columns,
- `"raw"`: numpy array of values in `y_col` column(s),
- `"sparse"`: 1D numpy array of integer labels, - `None`, no targets
are returned (the generator will only yield batches of image data,
which is useful to use in `model.predict_generator()`).
batch_size: Integer, size of a batch.
shuffle: Boolean, whether to shuffle the data between epochs.
seed: Random seed for data shuffling.
data_format: String, one of `channels_first`, `channels_last`.
save_to_dir: Optional directory where to save the pictures being yielded,
in a viewable format. This is useful for visualizing the random
transformations being applied, for debugging purposes.
save_prefix: String prefix to use for saving sample images (if
`save_to_dir` is set).
save_format: Format to use for saving sample images (if `save_to_dir` is
set).
subset: Subset of data (`"training"` or `"validation"`) if
validation_split is set in ImageDataGenerator.
interpolation: Interpolation method used to resample the image if the
target size is different from that of the loaded image. Supported
methods are "nearest", "bilinear", and "bicubic". If PIL version 1.1.3
or newer is installed, "lanczos" is also supported. If PIL version 3.4.0
or newer is installed, "box" and "hamming" are also supported. By
default, "nearest" is used.
dtype: Dtype to use for the generated arrays.
validate_filenames: Boolean, whether to validate image filenames in
`x_col`. If `True`, invalid images will be ignored. Disabling this
option
can lead to speed-up in the instantiation of this class. Default: `True`.
"""
def __init__(
self,
dataframe,
directory=None,
image_data_generator=None,
x_col='filename',
y_col='class',
weight_col=None,
target_size=(256, 256),
color_mode='rgb',
classes=None,
class_mode='categorical',
batch_size=32,
shuffle=True,
seed=None,
data_format='channels_last',
save_to_dir=None,
save_prefix='',
save_format='png',
subset=None,
interpolation='nearest',
dtype='float32',
validate_filenames=True):
super(DataFrameIterator, self).__init__(
dataframe=dataframe,
directory=directory,
image_data_generator=image_data_generator,
x_col=x_col,
y_col=y_col,
weight_col=weight_col,
target_size=target_size,
color_mode=color_mode,
classes=classes,
class_mode=class_mode,
batch_size=batch_size,
shuffle=shuffle,
seed=seed,
data_format=data_format,
save_to_dir=save_to_dir,
save_prefix=save_prefix,
save_format=save_format,
subset=subset,
interpolation=interpolation,
dtype=dtype,
validate_filenames=validate_filenames
)
@keras_export('keras.preprocessing.image.ImageDataGenerator')
class ImageDataGenerator(image.ImageDataGenerator):
"""Generate batches of tensor image data with real-time data augmentation.
@ -686,6 +805,302 @@ class ImageDataGenerator(image.ImageDataGenerator):
validation_split=validation_split,
**kwargs)
def flow(self,
x,
y=None,
batch_size=32,
shuffle=True,
sample_weight=None,
seed=None,
save_to_dir=None,
save_prefix='',
save_format='png',
subset=None):
"""Takes data & label arrays, generates batches of augmented data.
Arguments:
x: Input data. Numpy array of rank 4 or a tuple. If tuple, the first
element should contain the images and the second element another numpy
array or a list of numpy arrays that gets passed to the output without
any modifications. Can be used to feed the model miscellaneous data
along with the images. In case of grayscale data, the channels axis of
the image array should have value 1, in case of RGB data, it should
have value 3, and in case of RGBA data, it should have value 4.
y: Labels.
batch_size: Int (default: 32).
shuffle: Boolean (default: True).
sample_weight: Sample weights.
seed: Int (default: None).
save_to_dir: None or str (default: None). This allows you to optionally
specify a directory to which to save the augmented pictures being
generated (useful for visualizing what you are doing).
save_prefix: Str (default: `''`). Prefix to use for filenames of saved
pictures (only relevant if `save_to_dir` is set).
save_format: one of "png", "jpeg"
(only relevant if `save_to_dir` is set). Default: "png".
subset: Subset of data (`"training"` or `"validation"`) if
`validation_split` is set in `ImageDataGenerator`.
Returns:
An `Iterator` yielding tuples of `(x, y)`
where `x` is a numpy array of image data
(in the case of a single image input) or a list
of numpy arrays (in the case with
additional inputs) and `y` is a numpy array
of corresponding labels. If 'sample_weight' is not None,
the yielded tuples are of the form `(x, y, sample_weight)`.
If `y` is None, only the numpy array `x` is returned.
"""
return NumpyArrayIterator(
x,
y,
self,
batch_size=batch_size,
shuffle=shuffle,
sample_weight=sample_weight,
seed=seed,
data_format=self.data_format,
save_to_dir=save_to_dir,
save_prefix=save_prefix,
save_format=save_format,
subset=subset)
def flow_from_directory(self,
directory,
target_size=(256, 256),
color_mode='rgb',
classes=None,
class_mode='categorical',
batch_size=32,
shuffle=True,
seed=None,
save_to_dir=None,
save_prefix='',
save_format='png',
follow_links=False,
subset=None,
interpolation='nearest'):
"""Takes the path to a directory & generates batches of augmented data.
Arguments:
directory: string, path to the target directory. It should contain one
subdirectory per class. Any PNG, JPG, BMP, PPM or TIF images inside
each of the subdirectories directory tree will be included in the
generator. See [this script](
https://gist.github.com/fchollet/0830affa1f7f19fd47b06d4cf89ed44d)
for more details.
target_size: Tuple of integers `(height, width)`, defaults to `(256,
256)`. The dimensions to which all images found will be resized.
color_mode: One of "grayscale", "rgb", "rgba". Default: "rgb". Whether
the images will be converted to have 1, 3, or 4 channels.
classes: Optional list of class subdirectories
(e.g. `['dogs', 'cats']`). Default: None. If not provided, the list
of classes will be automatically inferred from the subdirectory
names/structure under `directory`, where each subdirectory will be
treated as a different class (and the order of the classes, which
will map to the label indices, will be alphanumeric). The
dictionary containing the mapping from class names to class
indices can be obtained via the attribute `class_indices`.
class_mode: One of "categorical", "binary", "sparse",
"input", or None. Default: "categorical".
Determines the type of label arrays that are returned: -
"categorical" will be 2D one-hot encoded labels, - "binary" will
be 1D binary labels, "sparse" will be 1D integer labels, - "input"
will be images identical to input images (mainly used to work with
autoencoders). - If None, no labels are returned (the generator
will only yield batches of image data, which is useful to use with
`model.predict_generator()`). Please note that in case of
class_mode None, the data still needs to reside in a subdirectory
of `directory` for it to work correctly.
batch_size: Size of the batches of data (default: 32).
shuffle: Whether to shuffle the data (default: True) If set to False,
sorts the data in alphanumeric order.
seed: Optional random seed for shuffling and transformations.
save_to_dir: None or str (default: None). This allows you to optionally
specify a directory to which to save the augmented pictures being
generated (useful for visualizing what you are doing).
save_prefix: Str. Prefix to use for filenames of saved pictures (only
relevant if `save_to_dir` is set).
save_format: One of "png", "jpeg"
(only relevant if `save_to_dir` is set). Default: "png".
follow_links: Whether to follow symlinks inside
class subdirectories (default: False).
subset: Subset of data (`"training"` or `"validation"`) if
`validation_split` is set in `ImageDataGenerator`.
interpolation: Interpolation method used to resample the image if the
target size is different from that of the loaded image. Supported
methods are `"nearest"`, `"bilinear"`, and `"bicubic"`. If PIL version
1.1.3 or newer is installed, `"lanczos"` is also supported. If PIL
version 3.4.0 or newer is installed, `"box"` and `"hamming"` are also
supported. By default, `"nearest"` is used.
Returns:
A `DirectoryIterator` yielding tuples of `(x, y)`
where `x` is a numpy array containing a batch
of images with shape `(batch_size, *target_size, channels)`
and `y` is a numpy array of corresponding labels.
"""
return DirectoryIterator(
directory,
self,
target_size=target_size,
color_mode=color_mode,
classes=classes,
class_mode=class_mode,
data_format=self.data_format,
batch_size=batch_size,
shuffle=shuffle,
seed=seed,
save_to_dir=save_to_dir,
save_prefix=save_prefix,
save_format=save_format,
follow_links=follow_links,
subset=subset,
interpolation=interpolation)
def flow_from_dataframe(self,
dataframe,
directory=None,
x_col='filename',
y_col='class',
weight_col=None,
target_size=(256, 256),
color_mode='rgb',
classes=None,
class_mode='categorical',
batch_size=32,
shuffle=True,
seed=None,
save_to_dir=None,
save_prefix='',
save_format='png',
subset=None,
interpolation='nearest',
validate_filenames=True,
**kwargs):
"""Takes the dataframe and the path to a directory + generates batches.
The generated batches contain augmented/normalized data.
**A simple tutorial can be found **[here](
http://bit.ly/keras_flow_from_dataframe).
Arguments:
dataframe: Pandas dataframe containing the filepaths relative to
`directory` (or absolute paths if `directory` is None) of the images
in a string column. It should include other column/s
depending on the `class_mode`: - if `class_mode` is `"categorical"`
(default value) it must include the `y_col` column with the
class/es of each image. Values in column can be string/list/tuple
if a single class or list/tuple if multiple classes. - if
`class_mode` is `"binary"` or `"sparse"` it must include the given
`y_col` column with class values as strings. - if `class_mode` is
`"raw"` or `"multi_output"` it should contain the columns
specified in `y_col`. - if `class_mode` is `"input"` or `None` no
extra column is needed.
directory: string, path to the directory to read images from. If `None`,
data in `x_col` column should be absolute paths.
x_col: string, column in `dataframe` that contains the filenames (or
absolute paths if `directory` is `None`).
y_col: string or list, column/s in `dataframe` that has the target data.
weight_col: string, column in `dataframe` that contains the sample
weights. Default: `None`.
target_size: tuple of integers `(height, width)`, default: `(256, 256)`.
The dimensions to which all images found will be resized.
color_mode: one of "grayscale", "rgb", "rgba". Default: "rgb". Whether
the images will be converted to have 1 or 3 color channels.
classes: optional list of classes (e.g. `['dogs', 'cats']`). Default is
None. If not provided, the list of classes will be automatically
inferred from the `y_col`, which will map to the label indices, will
be alphanumeric). The dictionary containing the mapping from class
names to class indices can be obtained via the attribute
`class_indices`.
class_mode: one of "binary", "categorical", "input", "multi_output",
"raw", sparse" or None. Default: "categorical".
Mode for yielding the targets:
- `"binary"`: 1D numpy array of binary labels,
- `"categorical"`: 2D numpy array of one-hot encoded labels.
Supports multi-label output.
- `"input"`: images identical to input images (mainly used to work
with autoencoders),
- `"multi_output"`: list with the values of the different columns,
- `"raw"`: numpy array of values in `y_col` column(s),
- `"sparse"`: 1D numpy array of integer labels, - `None`, no targets
are returned (the generator will only yield batches of image data,
which is useful to use in `model.predict_generator()`).
batch_size: size of the batches of data (default: 32).
shuffle: whether to shuffle the data (default: True)
seed: optional random seed for shuffling and transformations.
save_to_dir: None or str (default: None). This allows you to optionally
specify a directory to which to save the augmented pictures being
generated (useful for visualizing what you are doing).
save_prefix: str. Prefix to use for filenames of saved pictures (only
relevant if `save_to_dir` is set).
save_format: one of "png", "jpeg"
(only relevant if `save_to_dir` is set). Default: "png".
subset: Subset of data (`"training"` or `"validation"`) if
`validation_split` is set in `ImageDataGenerator`.
interpolation: Interpolation method used to resample the image if the
target size is different from that of the loaded image. Supported
methods are `"nearest"`, `"bilinear"`, and `"bicubic"`. If PIL version
1.1.3 or newer is installed, `"lanczos"` is also supported. If PIL
version 3.4.0 or newer is installed, `"box"` and `"hamming"` are also
supported. By default, `"nearest"` is used.
validate_filenames: Boolean, whether to validate image filenames in
`x_col`. If `True`, invalid images will be ignored. Disabling this
option can lead to speed-up in the execution of this function.
Defaults to `True`.
**kwargs: legacy arguments for raising deprecation warnings.
Returns:
A `DataFrameIterator` yielding tuples of `(x, y)`
where `x` is a numpy array containing a batch
of images with shape `(batch_size, *target_size, channels)`
and `y` is a numpy array of corresponding labels.
"""
if 'has_ext' in kwargs:
tf_logging.warn(
'has_ext is deprecated, filenames in the dataframe have '
'to match the exact filenames in disk.', DeprecationWarning)
if 'sort' in kwargs:
tf_logging.warn(
'sort is deprecated, batches will be created in the'
'same order than the filenames provided if shuffle'
'is set to False.', DeprecationWarning)
if class_mode == 'other':
tf_logging.warn(
'`class_mode` "other" is deprecated, please use '
'`class_mode` "raw".', DeprecationWarning)
class_mode = 'raw'
if 'drop_duplicates' in kwargs:
tf_logging.warn(
'drop_duplicates is deprecated, you can drop duplicates '
'by using the pandas.DataFrame.drop_duplicates method.',
DeprecationWarning)
return DataFrameIterator(
dataframe,
directory,
self,
x_col=x_col,
y_col=y_col,
weight_col=weight_col,
target_size=target_size,
color_mode=color_mode,
classes=classes,
class_mode=class_mode,
data_format=self.data_format,
batch_size=batch_size,
shuffle=shuffle,
seed=seed,
save_to_dir=save_to_dir,
save_prefix=save_prefix,
save_format=save_format,
subset=subset,
interpolation=interpolation,
validate_filenames=validate_filenames)
keras_export('keras.preprocessing.image.random_rotation')(random_rotation)
keras_export('keras.preprocessing.image.random_shift')(random_shift)
keras_export('keras.preprocessing.image.random_shear')(random_shear)

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@ -25,6 +25,9 @@ import tempfile
import numpy as np
from tensorflow.python.framework import test_util
from tensorflow.python.keras import keras_parameterized
from tensorflow.python.keras import layers
from tensorflow.python.keras.engine import sequential
from tensorflow.python.keras.preprocessing import image as preprocessing_image
from tensorflow.python.platform import test
@ -52,7 +55,7 @@ def _generate_test_images():
return [rgb_images, gray_images]
class TestImage(test.TestCase):
class TestImage(keras_parameterized.TestCase):
@test_util.run_v2_only
def test_smart_resize(self):
@ -319,14 +322,21 @@ class TestImage(test.TestCase):
self.assertEqual(
len(set(train_iterator.filenames) & set(filenames)), num_training)
model = sequential.Sequential([layers.Flatten(), layers.Dense(2)])
model.compile(optimizer='sgd', loss='mse')
model.fit(train_iterator, epochs=1)
shutil.rmtree(tmp_folder)
@keras_parameterized.run_all_keras_modes
def test_directory_iterator_with_validation_split_25_percent(self):
self.directory_iterator_with_validation_split_test_helper(0.25)
@keras_parameterized.run_all_keras_modes
def test_directory_iterator_with_validation_split_40_percent(self):
self.directory_iterator_with_validation_split_test_helper(0.40)
@keras_parameterized.run_all_keras_modes
def test_directory_iterator_with_validation_split_50_percent(self):
self.directory_iterator_with_validation_split_test_helper(0.50)