set_image_backend¶

paddle.vision.image. set_image_backend ( backend ) [源代码] ¶

在 ImageFolder 和 DatasetFolder 类中指定用于加载图像的后端。现在支持后端是 pillow 和 opencv。如果未设置后端，则默认使用 pil 。

参数¶

backend (str) - 加载图像的后端，必须为 pil 或者 cv2 。

代码示例¶

          >>> 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)

         