LinearizeDoubleSpline

class lsst.ip.isr.LinearizeDoubleSpline

Bases: LinearizeBase

Correct non-linearity with a spline model.

corrImage1 = uncorrImage - Spline1(coeffs, uncorrImage) corrImage = corrImage1 - Spline2(coeffs, corrImage1)

Notes

The spline fit calculates a correction as a function of the expected linear flux term. Because of this, the correction needs to be subtracted from the observed flux.

Attributes Summary

LinearityType

Methods Summary

__call__(image, **kwargs)

Correct for non-linearity.

Attributes Documentation

LinearityType = 'DoubleSpline'

Methods Documentation

__call__(image, **kwargs)

Correct for non-linearity.

Parameters:

imagelsst.afw.image.Image

Image to be corrected

kwargsdict

Dictionary of parameter keywords:

coeffs

Coefficient vector (list or np.ndarray).

log

Logger to handle messages (logging.Logger).

gain

Gain value to apply.

Returns:

outputtuple [bool, int]

If true, a correction was applied successfully. The integer indicates the number of pixels that were uncorrectable by being out of range.