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MultiplicativeNoise

Description

Apply multiplicative noise to the input image.

    This transform multiplies each pixel in the image by a random value or array of values,
    effectively creating a noise pattern that scales with the image intensity.

    Args:
        multiplier (tuple[float, float]): The range for the random multiplier.
            Defines the range from which the multiplier is sampled.
            Default: (0.9, 1.1)

        per_channel (bool): If True, use a different random multiplier for each channel.
            If False, use the same multiplier for all channels.
            Setting this to False is slightly faster.
            Default: False

        elementwise (bool): If True, generates a unique multiplier for each pixel.
            If False, generates a single multiplier (or one per channel if per_channel=True).
            Default: False

        p (float): Probability of applying the transform. Default: 0.5

    Targets:
        image

    Image types:
        uint8, float32

    Number of channels:
        Any

    Note:
        - When elementwise=False and per_channel=False, a single multiplier is applied to the entire image.
        - When elementwise=False and per_channel=True, each channel gets a different multiplier.
        - When elementwise=True and per_channel=False, each pixel gets the same multiplier across all channels.
        - When elementwise=True and per_channel=True, each pixel in each channel gets a unique multiplier.
        - Setting per_channel=False is slightly faster, especially for larger images.
        - This transform can be used to simulate various lighting conditions or to create noise that
          scales with image intensity.

    Example:
        >>> import numpy as np
        >>> import albumentations as A
        >>> image = np.random.randint(0, 256, (100, 100, 3), dtype=np.uint8)
        >>> transform = A.MultiplicativeNoise(multiplier=(0.9, 1.1), per_channel=True, p=1.0)
        >>> result = transform(image=image)
        >>> noisy_image = result["image"]

    References:
        - Multiplicative noise: https://en.wikipedia.org/wiki/Multiplicative_noise
    

Parameters

  • p: float (default: 0.5)
  • multiplier: tuple[float, float] (default: (0.9, 1.1))
  • per_channel: bool (default: false)
  • elementwise: bool (default: false)

Targets

  • Image

Try it out

Original Image (width = 484, height = 733):

Original

Transformed Image:

Transform not yet applied