adjust_gamma

torchvision.transforms.functional.adjust_gamma(img: torch.Tensor, gamma: float, gain: float = 1) → torch.Tensor

Perform gamma correction on an image.

Also known as Power Law Transform. Intensities in RGB mode are adjusted based on the following equation:

$$I_{\text{out}} = 255 \times \text{gain} \times \left(\frac{I_{\text{in}}}{255}\right)^{\gamma}$$

See Gamma Correction for more details.

Parameters

• img (PIL Image or Tensor) – PIL Image to be adjusted. If img is torch Tensor, it is expected to be in […, 1 or 3, H, W] format, where … means it can have an arbitrary number of leading dimensions. If img is PIL Image, modes with transparency (alpha channel) are not supported.

• gamma (float) – Non negative real number, same as $\gamma$ in the equation. gamma larger than 1 make the shadows darker, while gamma smaller than 1 make dark regions lighter.

• gain (float) – The constant multiplier.

Returns

Gamma correction adjusted image.

Return type

PIL Image or Tensor