You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Paddle/python/paddle/vision/image.py

163 lines
4.5 KiB

# Copyright (c) 2020 PaddlePaddle 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.
from PIL import Image
from paddle.utils import try_import
__all__ = ['set_image_backend', 'get_image_backend', 'image_load']
_image_backend = 'pil'
def set_image_backend(backend):
"""
Specifies the backend used to load images in class ``paddle.vision.datasets.ImageFolder``
and ``paddle.vision.datasets.DatasetFolder`` . Now support backends are pillow and opencv.
If backend not set, will use 'pil' as default.
Args:
backend (str): Name of the image load backend, should be one of {'pil', 'cv2'}.
Examples:
.. code-block:: python
import os
import shutil
import tempfile
import numpy as np
from PIL import Image
from paddle.vision import DatasetFolder
from paddle.vision import set_image_backend
set_image_backend('pil')
def make_fake_dir():
data_dir = tempfile.mkdtemp()
for i in range(2):
sub_dir = os.path.join(data_dir, 'class_' + str(i))
if not os.path.exists(sub_dir):
os.makedirs(sub_dir)
for j in range(2):
fake_img = Image.fromarray((np.random.random((32, 32, 3)) * 255).astype('uint8'))
fake_img.save(os.path.join(sub_dir, str(j) + '.png'))
return data_dir
temp_dir = make_fake_dir()
pil_data_folder = DatasetFolder(temp_dir)
for items in pil_data_folder:
break
# should get PIL.Image.Image
print(type(items[0]))
# use opencv as backend
# set_image_backend('cv2')
# cv2_data_folder = DatasetFolder(temp_dir)
# for items in cv2_data_folder:
# break
# should get numpy.ndarray
# print(type(items[0]))
shutil.rmtree(temp_dir)
"""
global _image_backend
if backend not in ['pil', 'cv2']:
raise ValueError(
"Expected backend are one of ['pil', 'cv2'], but got {}"
.format(backend))
_image_backend = backend
def get_image_backend():
"""
Gets the name of the package used to load images
Returns:
str: backend of image load.
Examples:
.. code-block:: python
from paddle.vision import get_image_backend
backend = get_image_backend()
print(backend)
"""
return _image_backend
def image_load(path, backend=None):
"""Load an image.
Args:
path (str): Path of the image.
backend (str, optional): The image decoding backend type. Options are
`cv2`, `pil`, `None`. If backend is None, the global _imread_backend
specified by ``paddle.vision.set_image_backend`` will be used. Default: None.
Returns:
PIL.Image or np.array: Loaded image.
Examples:
.. code-block:: python
import numpy as np
from PIL import Image
from paddle.vision import image_load, set_image_backend
fake_img = Image.fromarray((np.random.random((32, 32, 3)) * 255).astype('uint8'))
path = 'temp.png'
fake_img.save(path)
set_image_backend('pil')
pil_img = image_load(path).convert('RGB')
# should be PIL.Image.Image
print(type(pil_img))
# use opencv as backend
# set_image_backend('cv2')
# np_img = image_load(path)
# # should get numpy.ndarray
# print(type(np_img))
"""
if backend is None:
backend = _image_backend
if backend not in ['pil', 'cv2']:
raise ValueError(
"Expected backend are one of ['pil', 'cv2'], but got {}"
.format(backend))
if backend == 'pil':
return Image.open(path)
else:
cv2 = try_import('cv2')
return cv2.imread(path)