ContrastBiasStretch

class astropy.visualization.ContrastBiasStretch(contrast, bias)[source]

Bases: astropy.visualization.BaseStretch

A stretch that takes into account contrast and bias.

The stretch is given by:

\[y = (x - {\rm bias}) * {\rm contrast} + 0.5\]

and the output values are clipped to the [0:1] range.

Parameters:
contrast : float

The contrast parameter (see the above formula).

bias : float

The bias parameter (see the above formula).

Attributes Summary

inverse A stretch object that performs the inverse operation.

Methods Summary

__call__(self, values[, clip, out]) Transform values using this stretch.

Attributes Documentation

inverse

A stretch object that performs the inverse operation.

Methods Documentation

__call__(self, values, clip=True, out=None)[source]

Transform values using this stretch.

Parameters:
values : array-like

The input values, which should already be normalized to the [0:1] range.

clip : bool, optional

If True (default), values outside the [0:1] range are clipped to the [0:1] range.

out : ndarray, optional

If specified, the output values will be placed in this array (typically used for in-place calculations).

Returns:
result : ndarray

The transformed values.