AsinhMapping¶
- class lsst.afw.display.AsinhMapping(minimum, dataRange, Q=8)¶
Bases:
Mapping
A mapping for an asinh stretch (preserving colours independent of brightness)
x = asinh(Q (I - minimum)/range)/Q
Notes
This reduces to a linear stretch if Q == 0
See http://adsabs.harvard.edu/abs/2004PASP..116..133L
Methods Summary
intensity
(imageR, imageG, imageB)Return the total intensity from the red, blue, and green intensities
makeRgbImage
([imageR, imageG, imageB, ...])Convert 3 arrays, imageR, imageG, and imageB into a numpy RGB image
mapIntensityToUint8
(intensity)Return an array which, when multiplied by an image, returns that image mapped to the range of a uint8, [0, 255] (but not converted to uint8)
Methods Documentation
- intensity(imageR, imageG, imageB)¶
Return the total intensity from the red, blue, and green intensities
Notes
This is a naive computation, and may be overridden by subclasses
- makeRgbImage(imageR=None, imageG=None, imageB=None, xSize=None, ySize=None, rescaleFactor=None)¶
Convert 3 arrays, imageR, imageG, and imageB into a numpy RGB image
- imageR
lsst.afw.image.Image
ornumpy.ndarray
, (Nx, Ny) Image to map to red (if
None
, use the image passed to the ctor)- imageG
lsst.afw.image.Image
ornumpy.ndarray
, (Nx, Ny), optional Image to map to green (if
None
, use imageR)- imageB
lsst.afw.image.Image
ornumpy.ndarray
, (Nx, Ny), optional Image to map to blue (if
None
, use imageR)- xSize
int
, optional Desired width of RGB image. If
ySize
isNone
, preserve aspect ratio- ySize
int
, optional Desired height of RGB image
- rescaleFactor
float
, optional Make size of output image
rescaleFactor*size
of the input image
- imageR
- mapIntensityToUint8(intensity)¶
Return an array which, when multiplied by an image, returns that image mapped to the range of a uint8, [0, 255] (but not converted to uint8)
The intensity is assumed to have had minimum subtracted (as that can be done per-band)