Grayscale¶

class paddle.vision.transforms. Grayscale ( num_output_channels=1, keys=None ) [source]

Converts image to grayscale.

Parameters

• num_output_channels (int, optional) – (1 or 3) number of channels desired for output image. Default: 1.

• keys (list[str]|tuple[str], optional) – Same as BaseTransform. Default: None.

Shape:

• img(PIL.Image|np.ndarray|Paddle.Tensor): The input image with shape (H x W x C).

• output(PIL.Image|np.ndarray|Paddle.Tensor): Grayscale version of the input image.

  • If output_channels == 1 : returned image is single channel

  • If output_channels == 3 : returned image is 3 channel with r == g == b

Returns

A callable object of Grayscale.

Examples

>>> import numpy as np
>>> from PIL import Image
>>> from paddle.vision.transforms import Grayscale

>>> transform = Grayscale()
>>> fake_img = Image.fromarray((np.random.rand(224, 224, 3) * 255.).astype(np.uint8))
>>> fake_img = transform(fake_img)
>>> print(np.array(fake_img).shape)
(224, 224)