lsst.ip.diffim  16.0-18-geff7d6b+4
Public Member Functions | Public Attributes | Static Public Attributes | List of all members
lsst.ip.diffim.zogy.ZogyImagePsfMatchTask Class Reference
Inheritance diagram for lsst.ip.diffim.zogy.ZogyImagePsfMatchTask:
lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask lsst.ip.diffim.psfMatch.PsfMatchTask

Public Member Functions

def __init__ (self, args, kwargs)
 
def subtractExposures (self, templateExposure, scienceExposure, doWarping=True, spatiallyVarying=True, inImageSpace=False, doPreConvolve=False)
 
def subtractMaskedImages (self, templateExposure, scienceExposure, doWarping=True, spatiallyVarying=True, inImageSpace=False, doPreConvolve=False)
 
def getFwhmPix (self, psf)
 Return the FWHM in pixels of a Psf. More...
 
def matchExposures (self, templateExposure, scienceExposure, templateFwhmPix=None, scienceFwhmPix=None, candidateList=None, doWarping=True, convolveTemplate=True)
 Warp and PSF-match an exposure to the reference. More...
 
def matchMaskedImages (self, templateMaskedImage, scienceMaskedImage, candidateList, templateFwhmPix=None, scienceFwhmPix=None)
 PSF-match a MaskedImage (templateMaskedImage) to a reference MaskedImage (scienceMaskedImage) More...
 
def subtractExposures (self, templateExposure, scienceExposure, templateFwhmPix=None, scienceFwhmPix=None, candidateList=None, doWarping=True, convolveTemplate=True)
 Register, Psf-match and subtract two Exposures. More...
 
def subtractMaskedImages (self, templateMaskedImage, scienceMaskedImage, candidateList, templateFwhmPix=None, scienceFwhmPix=None)
 Psf-match and subtract two MaskedImages. More...
 
def getSelectSources (self, exposure, sigma=None, doSmooth=True, idFactory=None)
 Get sources to use for Psf-matching. More...
 
def makeCandidateList (self, templateExposure, scienceExposure, kernelSize, candidateList=None)
 Make a list of acceptable KernelCandidates. More...
 

Public Attributes

 kConfig
 
 background
 
 selectSchema
 
 selectAlgMetadata
 
 useRegularization
 
 hMat
 

Static Public Attributes

 ConfigClass = ZogyImagePsfMatchConfig
 

Detailed Description

Task to perform Zogy PSF matching and image subtraction.

This class inherits from ImagePsfMatchTask to contain the _warper
subtask and related methods.

Definition at line 1043 of file zogy.py.

Constructor & Destructor Documentation

◆ __init__()

def lsst.ip.diffim.zogy.ZogyImagePsfMatchTask.__init__ (   self,
  args,
  kwargs 
)

Definition at line 1052 of file zogy.py.

Member Function Documentation

◆ getFwhmPix()

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.getFwhmPix (   self,
  psf 
)
inherited

Return the FWHM in pixels of a Psf.

Definition at line 297 of file imagePsfMatch.py.

◆ getSelectSources()

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.getSelectSources (   self,
  exposure,
  sigma = None,
  doSmooth = True,
  idFactory = None 
)
inherited

Get sources to use for Psf-matching.

This method runs detection and measurement on an exposure. The returned set of sources will be used as candidates for Psf-matching.

Parameters
exposureExposure on which to run detection/measurement
sigmaDetection threshold
doSmoothWhether or not to smooth the Exposure with Psf before detection
idFactoryFactory for the generation of Source ids
Returns
source catalog containing candidates for the Psf-matching

Definition at line 621 of file imagePsfMatch.py.

◆ makeCandidateList()

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.makeCandidateList (   self,
  templateExposure,
  scienceExposure,
  kernelSize,
  candidateList = None 
)
inherited

Make a list of acceptable KernelCandidates.

Accept or generate a list of candidate sources for Psf-matching, and examine the Mask planes in both of the images for indications of bad pixels

Parameters
templateExposureExposure that will be convolved
scienceExposureExposure that will be matched-to
kernelSizeDimensions of the Psf-matching Kernel, used to grow detection footprints
candidateListList of Sources to examine. Elements must be of type afw.table.Source or a type that wraps a Source and has a getSource() method, such as meas.algorithms.PsfCandidateF.
Returns
a list of dicts having a "source" and "footprint" field for the Sources deemed to be appropriate for Psf matching

Definition at line 669 of file imagePsfMatch.py.

◆ matchExposures()

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.matchExposures (   self,
  templateExposure,
  scienceExposure,
  templateFwhmPix = None,
  scienceFwhmPix = None,
  candidateList = None,
  doWarping = True,
  convolveTemplate = True 
)
inherited

Warp and PSF-match an exposure to the reference.

Do the following, in order:

  • Warp templateExposure to match scienceExposure, if doWarping True and their WCSs do not already match
  • Determine a PSF matching kernel and differential background model that matches templateExposure to scienceExposure
  • Convolve templateExposure by PSF matching kernel
Parameters
templateExposureExposure to warp and PSF-match to the reference masked image
scienceExposureExposure whose WCS and PSF are to be matched to
templateFwhmPixFWHM (in pixels) of the Psf in the template image (image to convolve)
scienceFwhmPixFWHM (in pixels) of the Psf in the science image
candidateLista list of footprints/maskedImages for kernel candidates; if None then source detection is run.
  • Currently supported: list of Footprints or measAlg.PsfCandidateF
doWarpingwhat to do if templateExposure's and scienceExposure's WCSs do not match:
  • if True then warp templateExposure to match scienceExposure
  • if False then raise an Exception
convolveTemplateconvolve the template image or the science image
  • if True, templateExposure is warped if doWarping, templateExposure is convolved
  • if False, templateExposure is warped if doWarping, scienceExposure is convolved
Returns
a pipeBase.Struct containing these fields:
  • matchedImage: the PSF-matched exposure = warped templateExposure convolved by psfMatchingKernel. This has:
    • the same parent bbox, Wcs and Calib as scienceExposure
    • the same filter as templateExposure
    • no Psf (because the PSF-matching process does not compute one)
  • psfMatchingKernel: the PSF matching kernel
  • backgroundModel: differential background model
  • kernelCellSet: SpatialCellSet used to solve for the PSF matching kernel

Raise a RuntimeError if doWarping is False and templateExposure's and scienceExposure's WCSs do not match

Definition at line 305 of file imagePsfMatch.py.

◆ matchMaskedImages()

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.matchMaskedImages (   self,
  templateMaskedImage,
  scienceMaskedImage,
  candidateList,
  templateFwhmPix = None,
  scienceFwhmPix = None 
)
inherited

PSF-match a MaskedImage (templateMaskedImage) to a reference MaskedImage (scienceMaskedImage)

Do the following, in order:

  • Determine a PSF matching kernel and differential background model that matches templateMaskedImage to scienceMaskedImage
  • Convolve templateMaskedImage by the PSF matching kernel
Parameters
templateMaskedImagemasked image to PSF-match to the reference masked image; must be warped to match the reference masked image
scienceMaskedImagemaskedImage whose PSF is to be matched to
templateFwhmPixFWHM (in pixels) of the Psf in the template image (image to convolve)
scienceFwhmPixFWHM (in pixels) of the Psf in the science image
candidateLista list of footprints/maskedImages for kernel candidates; if None then source detection is run.
  • Currently supported: list of Footprints or measAlg.PsfCandidateF
Returns
a pipeBase.Struct containing these fields:
  • psfMatchedMaskedImage: the PSF-matched masked image = templateMaskedImage convolved with psfMatchingKernel. This has the same xy0, dimensions and wcs as scienceMaskedImage.
  • psfMatchingKernel: the PSF matching kernel
  • backgroundModel: differential background model
  • kernelCellSet: SpatialCellSet used to solve for the PSF matching kernel

Raise a RuntimeError if input images have different dimensions

Definition at line 389 of file imagePsfMatch.py.

◆ subtractExposures() [1/2]

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.subtractExposures (   self,
  templateExposure,
  scienceExposure,
  templateFwhmPix = None,
  scienceFwhmPix = None,
  candidateList = None,
  doWarping = True,
  convolveTemplate = True 
)
inherited

Register, Psf-match and subtract two Exposures.

Do the following, in order:

  • Warp templateExposure to match scienceExposure, if their WCSs do not already match
  • Determine a PSF matching kernel and differential background model that matches templateExposure to scienceExposure
  • PSF-match templateExposure to scienceExposure
  • Compute subtracted exposure (see return values for equation).
Parameters
templateExposureexposure to PSF-match to scienceExposure
scienceExposurereference Exposure
templateFwhmPixFWHM (in pixels) of the Psf in the template image (image to convolve)
scienceFwhmPixFWHM (in pixels) of the Psf in the science image
candidateLista list of footprints/maskedImages for kernel candidates; if None then source detection is run.
  • Currently supported: list of Footprints or measAlg.PsfCandidateF
doWarpingwhat to do if templateExposure's and scienceExposure's WCSs do not match:
  • if True then warp templateExposure to match scienceExposure
  • if False then raise an Exception
convolveTemplateconvolve the template image or the science image
  • if True, templateExposure is warped if doWarping, templateExposure is convolved
  • if False, templateExposure is warped if doWarping, scienceExposure is convolved
Returns
a pipeBase.Struct containing these fields:
  • subtractedExposure: subtracted Exposure = scienceExposure - (matchedImage + backgroundModel)
  • matchedImage: templateExposure after warping to match templateExposure (if doWarping true), and convolving with psfMatchingKernel
  • psfMatchingKernel: PSF matching kernel
  • backgroundModel: differential background model
  • kernelCellSet: SpatialCellSet used to determine PSF matching kernel

Definition at line 484 of file imagePsfMatch.py.

◆ subtractExposures() [2/2]

def lsst.ip.diffim.zogy.ZogyImagePsfMatchTask.subtractExposures (   self,
  templateExposure,
  scienceExposure,
  doWarping = True,
  spatiallyVarying = True,
  inImageSpace = False,
  doPreConvolve = False 
)
Register, PSF-match, and subtract two Exposures using the ZOGY algorithm.

Do the following, in order:
- Warp templateExposure to match scienceExposure, if their WCSs do not already match
- Compute subtracted exposure ZOGY image subtraction algorithm on the two exposures

Parameters
----------
templateExposure : `lsst.afw.image.Exposure`
    exposure to PSF-match to scienceExposure. The exposure's mean value is subtracted
    in-place.
scienceExposure : `lsst.afw.image.Exposure`
    reference Exposure. The exposure's mean value is subtracted in-place.
doWarping : `bool`
    what to do if templateExposure's and scienceExposure's WCSs do not match:
    - if True then warp templateExposure to match scienceExposure
    - if False then raise an Exception
spatiallyVarying : bool
    If True, perform the operation over a grid of patches across the two exposures
inImageSpace : `bool`
    If True, perform the Zogy convolutions in image space rather than in frequency space.
doPreConvolve : `bool`
    ***Currently not implemented.*** If True assume we are to compute the match filter-convolved
    exposure which can be thresholded for detection. In the case of Zogy this would mean
    we compute the Scorr image.

Returns
-------
A `lsst.pipe.base.Struct` containing these fields:
- subtractedExposure: subtracted Exposure
- warpedExposure: templateExposure after warping to match scienceExposure (if doWarping true)

Definition at line 1072 of file zogy.py.

◆ subtractMaskedImages() [1/2]

def lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.subtractMaskedImages (   self,
  templateMaskedImage,
  scienceMaskedImage,
  candidateList,
  templateFwhmPix = None,
  scienceFwhmPix = None 
)
inherited

Psf-match and subtract two MaskedImages.

Do the following, in order:

  • PSF-match templateMaskedImage to scienceMaskedImage
  • Determine the differential background
  • Return the difference: scienceMaskedImage - ((warped templateMaskedImage convolved with psfMatchingKernel) + backgroundModel)
Parameters
templateMaskedImageMaskedImage to PSF-match to scienceMaskedImage
scienceMaskedImagereference MaskedImage
templateFwhmPixFWHM (in pixels) of the Psf in the template image (image to convolve)
scienceFwhmPixFWHM (in pixels) of the Psf in the science image
candidateLista list of footprints/maskedImages for kernel candidates; if None then source detection is run.
  • Currently supported: list of Footprints or measAlg.PsfCandidateF
Returns
a pipeBase.Struct containing these fields:
  • subtractedMaskedImage = scienceMaskedImage - (matchedImage + backgroundModel)
  • matchedImage: templateMaskedImage convolved with psfMatchingKernel
  • psfMatchingKernel: PSF matching kernel
  • backgroundModel: differential background model
  • kernelCellSet: SpatialCellSet used to determine PSF matching kernel

Definition at line 567 of file imagePsfMatch.py.

◆ subtractMaskedImages() [2/2]

def lsst.ip.diffim.zogy.ZogyImagePsfMatchTask.subtractMaskedImages (   self,
  templateExposure,
  scienceExposure,
  doWarping = True,
  spatiallyVarying = True,
  inImageSpace = False,
  doPreConvolve = False 
)

Definition at line 1182 of file zogy.py.

Member Data Documentation

◆ background

lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.background
inherited

Definition at line 290 of file imagePsfMatch.py.

◆ ConfigClass

lsst.ip.diffim.zogy.ZogyImagePsfMatchTask.ConfigClass = ZogyImagePsfMatchConfig
static

Definition at line 1050 of file zogy.py.

◆ hMat

lsst.ip.diffim.psfMatch.PsfMatchTask.hMat
inherited

Definition at line 702 of file psfMatch.py.

◆ kConfig

lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.kConfig
inherited

Definition at line 286 of file imagePsfMatch.py.

◆ selectAlgMetadata

lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.selectAlgMetadata
inherited

Definition at line 293 of file imagePsfMatch.py.

◆ selectSchema

lsst.ip.diffim.imagePsfMatch.ImagePsfMatchTask.selectSchema
inherited

Definition at line 292 of file imagePsfMatch.py.

◆ useRegularization

lsst.ip.diffim.psfMatch.PsfMatchTask.useRegularization
inherited

Definition at line 697 of file psfMatch.py.


The documentation for this class was generated from the following file: