#!/usr/bin/env python3
# Copyright 2019 Christian Henning
#
# 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.
#
# @title :data/cifar100_data.py
# @author :ch
# @contact :henningc@ethz.ch
# @created :05/02/2019
# @version :1.0
# @python_version :3.6.8
"""
CIFAR-100 Dataset
-----------------
The module :mod:`data.cifar100_data` contains a handler for the CIFAR 100
dataset.
The dataset consists of 60000 32x32 colour images in 100 classes, with 600
images per class. There are 50000 training images and 10000 test images.
Information about the dataset can be retrieved from:
https://www.cs.toronto.edu/~kriz/cifar.html
"""
# FIXME: The content of this module is mostly a copy of the module
# 'cifar10_data'. These two should be merged in future.
import os
import numpy as np
import time
import _pickle as pickle
import urllib.request
import tarfile
import matplotlib.pyplot as plt
from hypnettorch.data.dataset import Dataset
from hypnettorch.data.cifar10_data import CIFAR10Data
[docs]class CIFAR100Data(Dataset):
"""An instance of the class shall represent the CIFAR-100 dataset.
Args:
data_path (str): Where should the dataset be read from? If not existing,
the dataset will be downloaded into this folder.
use_one_hot (bool): Whether the class labels should be represented in a
one-hot encoding.
use_data_augmentation (bool): Note, this option currently only applies
to input batches that are transformed using the class member
:meth:`input_to_torch_tensor` (hence, **only available for
PyTorch**, so far).
Note:
If activated, the statistics of test samples are changed as
a normalization is applied (identical to the of class
:class:`data.cifar10_data.CIFAR10Data`).
validation_size (int): The number of validation samples. Validation
samples will be taking from the training set (the first :math:`n`
samples).
use_cutout (bool): Whether option ``apply_cutout`` should be set of
method :meth:`torch_input_transforms`. We use cutouts of size
``8 x 8`` as recommended
`here <https://arxiv.org/pdf/1708.04552.pdf>`__.
Note:
Only applies if ``use_data_augmentation`` is set.
"""
_DOWNLOAD_PATH = 'https://www.cs.toronto.edu/~kriz/'
_DOWNLOAD_FILE = 'cifar-100-python.tar.gz'
_EXTRACTED_FOLDER = 'cifar-100-python'
_TRAIN_BATCH_FN = 'train'
_TEST_BATCH_FN = 'test'
_META_DATA_FN = 'meta'
def __init__(self, data_path, use_one_hot=False,
use_data_augmentation=False, validation_size=5000,
use_cutout=False):
super().__init__()
start = time.time()
print('Reading CIFAR-100 dataset ...')
if not os.path.exists(data_path):
print('Creating directory "%s" ...' % (data_path))
os.makedirs(data_path)
extracted_data_dir = os.path.join(data_path,
CIFAR100Data._EXTRACTED_FOLDER)
archive_fn = os.path.join(data_path, CIFAR100Data._DOWNLOAD_FILE)
if not os.path.exists(extracted_data_dir):
print('Downloading dataset ...')
urllib.request.urlretrieve(CIFAR100Data._DOWNLOAD_PATH + \
CIFAR100Data._DOWNLOAD_FILE, \
archive_fn)
# Extract downloaded dataset.
tar = tarfile.open(archive_fn, "r:gz")
tar.extractall(path=data_path)
tar.close()
os.remove(archive_fn)
train_batch_fn = os.path.join(extracted_data_dir,
CIFAR100Data._TRAIN_BATCH_FN)
test_batch_fn = os.path.join(extracted_data_dir,
CIFAR100Data._TEST_BATCH_FN)
meta_fn = os.path.join(extracted_data_dir,
CIFAR100Data._META_DATA_FN)
assert(os.path.exists(train_batch_fn) and
os.path.exists(test_batch_fn) and os.path.exists(meta_fn))
self._data['classification'] = True
self._data['sequence'] = False
self._data['num_classes'] = 100
self._data['is_one_hot'] = use_one_hot
self._data['in_shape'] = [32, 32, 3]
self._data['out_shape'] = [100 if use_one_hot else 1]
# Fill the remaining _data fields with the information read from
# the downloaded files.
self._read_meta(meta_fn)
self._read_batches(train_batch_fn, test_batch_fn, validation_size)
# Initialize PyTorch data augmentation.
self._augment_inputs = False
if use_data_augmentation:
self._augment_inputs = True
self._train_transform, self._test_transform = \
CIFAR10Data.torch_input_transforms(apply_rand_hflips=True,
apply_cutout=use_cutout, cutout_length=8)
end = time.time()
print('Elapsed time to read dataset: %f sec' % (end-start))
def _read_meta(self, filename):
"""Read the meta data file.
This method will add an additional field to the _data attribute named
"cifar100". This dictionary will be filled with two members:
* "fine_label_names": The names of the associated categorical class
labels.
* "coarse_label_names": The names of the 20 coarse labels that are
associated to each sample.
Args:
filename: The path to the meta data file.
"""
with open(filename, 'rb') as f:
meta_data = pickle.load(f, encoding='UTF-8')
self._data['cifar100'] = dict()
self._data['cifar100']['fine_label_names'] = \
meta_data['fine_label_names']
self._data['cifar100']['coarse_label_names'] = \
meta_data['coarse_label_names']
def _read_batches(self, train_fn, test_fn, validation_size):
"""Read training and testing batch from files.
The method fills the remaining mandatory fields of the _data attribute,
that have not been set yet in the constructor.
The images are converted to match the output shape (32, 32, 3) and
scaled to have values between 0 and 1. For labels, the correct encoding
is enforced.
Args:
train_fn: Filepath of the train batch.
test_fn: Filepath of the test batch.
validation_size: Number of validation samples.
"""
# Read test batch.
with open(test_fn, 'rb') as f:
test_batch = pickle.load(f, encoding='bytes')
# Note, that we ignore the two keys: "batch_label", "coarse_labels" and
# "filenames".
test_labels = np.array(test_batch['fine_labels'.encode()])
test_samples = test_batch['data'.encode()]
# Read test batch.
with open(train_fn, 'rb') as f:
train_batch = pickle.load(f, encoding='bytes')
train_labels = np.array(train_batch['fine_labels'.encode()])
train_samples = train_batch['data'.encode()]
if validation_size > 0:
if validation_size >= train_labels.shape[0]:
raise ValueError('Validation set must contain less than %d ' \
% (train_labels.shape[0]) + 'samples!')
val_inds = np.arange(validation_size)
train_inds = np.arange(validation_size, train_labels.size)
else:
train_inds = np.arange(train_labels.size)
test_inds = np.arange(train_labels.size,
train_labels.size + test_labels.size)
labels = np.concatenate([train_labels, test_labels])
labels = np.reshape(labels, (-1, 1))
images = np.concatenate([train_samples, test_samples], axis=0)
# Note, images are currently encoded in a way, that there shape
# corresponds to (3, 32, 32). For consistency reasons, we would like to
# change that to (32, 32, 3).
images = np.reshape(images, (-1, 3, 32, 32))
images = np.rollaxis(images, 1, 4)
images = np.reshape(images, (-1, 32 * 32 * 3))
# Scale images into a range between 0 and 1.
images = images / 255
self._data['in_data'] = images
self._data['train_inds'] = train_inds
self._data['test_inds'] = test_inds
if validation_size > 0:
self._data['val_inds'] = val_inds
if self._data['is_one_hot']:
labels = self._to_one_hot(labels)
self._data['out_data'] = labels
[docs] def get_identifier(self):
"""Returns the name of the dataset."""
return 'CIFAR-100'
def _plot_sample(self, fig, inner_grid, num_inner_plots, ind, inputs,
outputs=None, predictions=None):
"""Implementation of abstract method
:meth:`data.dataset.Dataset._plot_sample`.
"""
ax = plt.Subplot(fig, inner_grid[0])
if outputs is None:
ax.set_title("CIFAR-100 Sample")
else:
assert(np.size(outputs) == 1)
label = np.asscalar(outputs)
label_name = self._data['cifar100']['fine_label_names'][label]
if predictions is None:
ax.set_title('Label of shown sample:\n%s (%d)' % \
(label_name, label))
else:
if np.size(predictions) == self.num_classes:
pred_label = np.argmax(predictions)
else:
pred_label = np.asscalar(predictions)
pred_label_name = \
self._data['cifar100']['fine_label_names'][pred_label]
ax.set_title('Label of shown sample:\n%s (%d)' % \
(label_name, label) + '\nPrediction: %s (%d)' % \
(pred_label_name, pred_label))
ax.set_axis_off()
ax.imshow(np.squeeze(np.reshape(inputs, self.in_shape)))
fig.add_subplot(ax)
if num_inner_plots == 2:
ax = plt.Subplot(fig, inner_grid[1])
ax.set_title('Predictions')
bars = ax.bar(range(self.num_classes), np.squeeze(predictions))
ax.set_xticks(range(self.num_classes))
if outputs is not None:
bars[int(label)].set_color('r')
fig.add_subplot(ax)
def _plot_config(self, inputs, outputs=None, predictions=None):
"""Re-Implementation of method
:meth:`data.dataset.Dataset._plot_config`.
This method has been overriden to ensure, that there are 2 subplots,
in case the predictions are given.
"""
plot_configs = super()._plot_config(inputs, outputs=outputs,
predictions=predictions)
if predictions is not None and \
np.shape(predictions)[1] == self.num_classes:
plot_configs['outer_hspace'] = 0.6
plot_configs['inner_hspace'] = 0.4
plot_configs['num_inner_rows'] = 2
#plot_configs['num_inner_cols'] = 1
plot_configs['num_inner_plots'] = 2
return plot_configs
if __name__ == '__main__':
pass