nw_arcsinh

pydl.pydlutils.rgbcolor.nw_arcsinh(colors, nonlinearity=3.0)

Scales colors by a degree of nonlinearity specified by user.

The input image must have zero background (i.e., it must already be background-subtracted).

Parameters:

colors : ndarray

3D Array containing RGB image. The dimensions should be (X, Y, 3).

nonlinearity : float

Amount of nonlinear scaling. If set to zero, no scaling will be performed (this is equivalent to linear scaling).

Returns:

:class:`~numpy.ndarray`

The scaled image.

Raises:

:exc:`ValueError`

If colors has the wrong shape.