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- scale_image

# scale_image

`astropy.visualization.``scale_image`(image, scale='linear', power=1.0, asinh_a=0.1, min_cut=None, max_cut=None, min_percent=None, max_percent=None, percent=None, clip=True)

  Perform scaling/stretching of an image between minimum and maximum cut levels.

  Parameters:

  image : array-like

  > The array of values.

  scale : {{‘linear’, ‘sqrt’, ‘power’, log’, ‘asinh’}}

  > The scaling/stretch function to apply to the image. The default is ‘linear’.

  power : float, optional

  > The power index for `scale='power'` image scaling. The default is 1.0.

  asinh_a : float, optional

  > For `scale='asinh'` image scaling, the value where the asinh curve transitions from linear to logarithmic behavior, expressed as a fraction of the normalized image. Must be in the range between 0 and 1.

  min_cut : float, optional

  > The pixel value of the minimum cut level. Data values less than `min_cut` will set to `min_cut` before scaling the image. The default is the image minimum. `min_cut` overrides `min_percent`.

  max_cut : float, optional

  > The pixel value of the maximum cut level. Data values greater than `min_cut` will set to `min_cut` before scaling the image. The default is the image maximum. `max_cut` overrides `max_percent`.

  min_percent : float, optional

  > The percentile value used to determine the pixel value of minimum cut level. The default is 0.0. `min_percent` overrides `percent`.

  max_percent : float, optional

  > The percentile value used to determine the pixel value of maximum cut level. The default is 100.0. `max_percent` overrides `percent`.

  percent : float, optional

  > The percentage of the image values used to determine the pixel values of the minimum and maximum cut levels. The lower cut level will set at the `(100 - percent) / 2` percentile, while the upper cut level will be set at the `(100 + percent) / 2` percentile. The default is 100.0. `percent` is ignored if either `min_percent` or `max_percent` is input.

  clip : bool, optional

  > Whether to clip the result to the range [0:1].

  Returns:

  image : ndarray

  > The array of the scaled/stretched image with a minimum of 0.0 and a maximum of 1.0.