set_image_backend¶

paddle.vision. set_image_backend ( backend ) [source]

Specifies the backend used to load images in class api_paddle_datasets_ImageFolder and api_paddle_datasets_DatasetFolder . Now support backends are pillow and opencv. If backend not set, will use ‘pil’ as default.

Parameters

backend (str) – Name of the image load backend, should be one of {‘pil’, ‘cv2’}.

Examples

>>> 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

>>> print(type(items[0]))
<class 'PIL.Image.Image'>

>>> # use opencv as backend
>>> set_image_backend('cv2')

>>> cv2_data_folder = DatasetFolder(temp_dir)

>>> for items in cv2_data_folder:
...     break

>>> print(type(items[0]))
<class 'numpy.ndarray'>

>>> shutil.rmtree(temp_dir)