Coverage for python/lsst/meas/extensions/gaap/_gaap.py: 27%
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1# This file is part of meas_extensions_gaap
2#
3# Developed for the LSST Data Management System.
4# This product includes software developed by the LSST Project
5# (http://www.lsst.org/).
6# See the COPYRIGHT file at the top-level directory of this distribution
7# for details of code ownership.
8#
9# This program is free software: you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation, either version 3 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the LSST License Statement and
20# the GNU General Public License along with this program. If not,
21# see <http://www.lsstcorp.org/LegalNotices/>.
23from __future__ import annotations
25__all__ = ("SingleFrameGaapFluxPlugin", "SingleFrameGaapFluxConfig",
26 "ForcedGaapFluxPlugin", "ForcedGaapFluxConfig")
28from typing import Generator, Optional, Union
29from functools import partial
30import itertools
31import logging
32import lsst.afw.detection as afwDetection
33import lsst.afw.image as afwImage
34import lsst.afw.geom as afwGeom
35import lsst.afw.table as afwTable
36import lsst.geom
37import lsst.meas.base as measBase
38import lsst.pex.config as pexConfig
39from lsst.pex.exceptions import InvalidParameterError
40import scipy.signal
41from ._gaussianizePsf import GaussianizePsfTask
43PLUGIN_NAME = "ext_gaap_GaapFlux"
46class GaapConvolutionError(measBase.MeasurementError):
47 """Collection of any unexpected errors in GAaP during PSF Gaussianization.
49 The PSF Gaussianization procedure using `modelPsfMatchTask` may throw
50 exceptions for certain target PSFs. Such errors are caught until all
51 measurements are at least attempted. The complete traceback information
52 is lost, but unique error messages are preserved.
54 Parameters
55 ----------
56 errors : `dict` [`str`, `Exception`]
57 The values are exceptions raised, while the keys are the loop variables
58 (in `str` format) where the exceptions were raised.
59 """
60 def __init__(self, errors: dict[str, Exception]):
61 self.errorDict = errors
62 message = "Problematic scaling factors = "
63 message += ", ".join(errors)
64 message += " Errors: "
65 message += " | ".join(set(msg.__repr__() for msg in errors.values())) # msg.cpp.what() misses type
66 super().__init__(message, 1) # the second argument does not matter.
69class NoPixelError(Exception):
70 """Raised when the footprint has no pixels.
72 This is caught by the measurement framework, which then calls the
73 `fail` method of the plugin without passing in a value for `error`.
74 """
77class BaseGaapFluxConfig(measBase.BaseMeasurementPluginConfig):
78 """Configuration parameters for Gaussian Aperture and PSF (GAaP) plugin.
79 """
80 def _greaterThanOrEqualToUnity(x: float) -> bool: # noqa: N805
81 """Returns True if the input ``x`` is greater than 1.0, else False.
82 """
83 return x >= 1
85 def _isOdd(x: int) -> bool: # noqa: N805
86 """Returns True if the input ``x`` is positive and odd, else False.
87 """
88 return (x%2 == 1) & (x > 0)
90 sigmas = pexConfig.ListField(
91 dtype=float,
92 default=[0.7, 1.0],
93 doc="List of sigmas (in arcseconds) of circular Gaussian apertures to apply on "
94 "pre-seeing galaxy images. These should be somewhat larger than the PSF "
95 "(determined by ``scalingFactors``) to avoid measurement failures."
96 )
98 scalingFactors = pexConfig.ListField(
99 dtype=float,
100 default=[1.15],
101 itemCheck=_greaterThanOrEqualToUnity,
102 doc="List of factors with which the seeing should be scaled to obtain the "
103 "sigma values of the target Gaussian PSF. The factor should not be less "
104 "than unity to avoid the PSF matching task to go into deconvolution mode "
105 "and should ideally be slightly greater than unity. The runtime of the "
106 "plugin scales linearly with the number of elements in the list."
107 )
109 _modelPsfMatch = pexConfig.ConfigurableField(
110 target=GaussianizePsfTask,
111 doc="PSF Gaussianization Task"
112 )
114 _modelPsfDimension = pexConfig.Field(
115 dtype=int,
116 default=65,
117 check=_isOdd,
118 doc="The dimensions (width and height) of the target PSF image in pixels. Must be odd."
119 )
121 doPsfPhotometry = pexConfig.Field(
122 dtype=bool,
123 default=False,
124 doc="Perform PSF photometry after PSF-Gaussianization to validate Gaussianization accuracy? "
125 "This does not produce consistent color estimates. If setting it to `True`, it must be done so "
126 "prior to registering the plugin for aperture correction if ``registerForApCorr`` is also `True`."
127 )
129 doOptimalPhotometry = pexConfig.Field(
130 dtype=bool,
131 default=True,
132 doc="Perform optimal photometry with near maximal SNR using an adaptive elliptical aperture? "
133 "This requires a shape algorithm to have been run previously."
134 )
136 registerForApCorr = pexConfig.Field(
137 dtype=bool,
138 default=True,
139 doc="Register measurements for aperture correction? "
140 "The aperture correction registration is done when the plugin is instatiated and not "
141 "during import because the column names are derived from the configuration rather than being "
142 "static. Sometimes you want to turn this off, e.g., when you use aperture corrections derived "
143 "from somewhere else through a 'proxy' mechanism."
144 )
146 # scaleByFwm is the only config field of modelPsfMatch Task that we allow
147 # the user to set without explicitly setting the modelPsfMatch config.
148 # It is intended to abstract away the underlying implementation.
149 @property
150 def scaleByFwhm(self) -> bool:
151 """Config parameter of the PSF Matching task.
152 Scale kernelSize, alardGaussians by input Fwhm?
153 """
154 return self._modelPsfMatch.kernel.active.scaleByFwhm
156 @scaleByFwhm.setter
157 def scaleByFwhm(self, value: bool) -> None:
158 self._modelPsfMatch.kernel.active.scaleByFwhm = value
160 @property
161 def gaussianizationMethod(self) -> str:
162 """Type of convolution to use for PSF-Gaussianization."""
163 return self._modelPsfMatch.convolutionMethod
165 @gaussianizationMethod.setter
166 def gaussianizationMethod(self, value: str) -> None:
167 self._modelPsfMatch.convolutionMethod = value
169 @property
170 def _sigmas(self) -> list:
171 """List of values set in ``sigmas`` along with special apertures such
172 as "PsfFlux" and "Optimal" if applicable.
173 """
174 return self.sigmas.list() + ["PsfFlux"]*self.doPsfPhotometry + ["Optimal"]*self.doOptimalPhotometry
176 def setDefaults(self) -> None:
177 # Docstring inherited
178 # TODO: DM-27482 might change these values.
179 self._modelPsfMatch.kernel.active.alardNGauss = 1
180 self._modelPsfMatch.kernel.active.alardDegGaussDeconv = 1
181 self._modelPsfMatch.kernel.active.alardDegGauss = [4]
182 self._modelPsfMatch.kernel.active.alardGaussBeta = 1.0
183 self._modelPsfMatch.kernel.active.spatialKernelOrder = 0
184 self.scaleByFwhm = True
186 def validate(self):
187 super().validate()
188 self._modelPsfMatch.validate()
189 assert self._modelPsfMatch.kernel.active.alardNGauss == 1
191 @staticmethod
192 def _getGaapResultName(scalingFactor: float, sigma: Union[float, str], name: Optional[str] = None) -> str:
193 """Return the base name for GAaP fields
195 For example, for a scaling factor of 1.15 for seeing and sigma of the
196 effective Gaussian aperture of 0.7 arcsec, the returned value would be
197 "ext_gaap_GaapFlux_1_15x_0_7".
199 Notes
200 -----
201 Being a static method, this does not check if measurements correspond
202 to the input arguments. Instead, users should use
203 `getAllGaapResultNames` to obtain the full list of base names.
205 This is not a config-y thing, but is placed here to make the fieldnames
206 from GAaP measurements available outside the plugin.
208 Parameters
209 ----------
210 scalingFactor : `float`
211 The factor by which the trace radius of the PSF must be scaled.
212 sigma : `float` or `str`
213 Sigma of the effective Gaussian aperture (PSF-convolved explicit
214 aperture) or "PsfFlux" for PSF photometry post PSF-Gaussianization.
215 name : `str`, optional
216 The exact registered name of the GAaP plugin, typically either
217 "ext_gaap_GaapFlux" or "undeblended_ext_gaap_GaapFlux". If ``name``
218 is None, then only the middle part (1_15x_0_7 in the example)
219 without the leading underscore is returned.
221 Returns
222 -------
223 baseName : `str`
224 Base name for GAaP field.
225 """
226 suffix = "_".join((str(scalingFactor).replace(".", "_")+"x", str(sigma).replace(".", "_")))
227 if name is None:
228 return suffix
229 return "_".join((name, suffix))
231 def getAllGaapResultNames(self, name: Optional[str] = PLUGIN_NAME) -> Generator[str]:
232 """Generate the base names for all of the GAaP fields.
234 For example, if the plugin is configured with `scalingFactors` = [1.15]
235 and `sigmas` = [0.7, 1.0] the returned expression would yield
236 ("ext_gaap_GaapFlux_1_15x_0_7", "ext_gaap_GaapFlux_1_15x_1_0") when
237 called with ``name`` = "ext_gaap_GaapFlux". It will also generate
238 "ext_gaap_GaapFlux_1_15x_PsfFlux" if `doPsfPhotometry` is True.
240 Parameters
241 ----------
242 name : `str`, optional
243 The exact registered name of the GAaP plugin, typically either
244 "ext_gaap_GaapFlux" or "undeblended_ext_gaap_GaapFlux". If ``name``
245 is None, then only the middle parts (("1_15x_0_7", "1_15x_1_0"),
246 for example) without the leading underscores are returned.
248 Returns
249 -------
250 baseNames : `generator`
251 A generator expression yielding all the base names.
252 """
253 scalingFactors = self.scalingFactors
254 sigmas = self._sigmas
255 baseNames = (self._getGaapResultName(scalingFactor, sigma, name)
256 for scalingFactor, sigma in itertools.product(scalingFactors, sigmas))
257 return baseNames
260class BaseGaapFluxMixin:
261 """Mixin base class for Gaussian-Aperture and PSF (GAaP) photometry
262 algorithm.
264 This class does almost all the heavy-lifting for its two derived classes,
265 SingleFrameGaapFluxPlugin and ForcedGaapFluxPlugin which simply adapt it to
266 the slightly different interfaces for single-frame and forced measurement.
267 This class implements the GAaP algorithm and is intended for code reuse
268 by the two concrete derived classes by including this mixin class.
270 Parameters
271 ----------
272 config : `BaseGaapFluxConfig`
273 Plugin configuration.
274 name : `str`
275 Plugin name, for registering.
276 schema : `lsst.afw.table.Schema`
277 The schema for the measurement output catalog. New fields will be added
278 to hold measurements produced by this plugin.
279 logName : `str`, optional
280 Name to use when logging errors. This is typically provided by the
281 measurement framework.
283 Raises
284 ------
285 GaapConvolutionError
286 Raised if the PSF Gaussianization fails for one or more target PSFs.
287 lsst.meas.base.FatalAlgorithmError
288 Raised if the Exposure does not contain a PSF model.
289 """
291 ConfigClass = BaseGaapFluxConfig
292 hasLogName = True
294 def __init__(self, config: BaseGaapFluxConfig, name, schema, logName=None) -> None:
295 # Flag definitions for each variant of GAaP measurement
296 flagDefs = measBase.FlagDefinitionList()
297 for scalingFactor, sigma in itertools.product(config.scalingFactors, config.sigmas):
298 baseName = self.ConfigClass._getGaapResultName(scalingFactor, sigma, name)
299 doc = f"GAaP Flux with {sigma} aperture after multiplying the seeing by {scalingFactor}"
300 measBase.FluxResultKey.addFields(schema, name=baseName, doc=doc)
302 # Remove the prefix_ since FlagHandler prepends it
303 middleName = self.ConfigClass._getGaapResultName(scalingFactor, sigma)
304 flagDefs.add(schema.join(middleName, "flag_bigPsf"), "The Gaussianized PSF is "
305 "bigger than the aperture")
306 flagDefs.add(schema.join(middleName, "flag"), "Generic failure flag for this set of config "
307 "parameters. ")
309 # PSF photometry
310 if config.doPsfPhotometry:
311 for scalingFactor in config.scalingFactors:
312 baseName = self.ConfigClass._getGaapResultName(scalingFactor, "PsfFlux", name)
313 doc = f"GAaP Flux with PSF aperture after multiplying the seeing by {scalingFactor}"
314 measBase.FluxResultKey.addFields(schema, name=baseName, doc=doc)
316 # Remove the prefix_ since FlagHandler prepends it
317 middleName = self.ConfigClass._getGaapResultName(scalingFactor, "PsfFlux")
318 flagDefs.add(schema.join(middleName, "flag"), "Generic failure flag for this set of config "
319 "parameters. ")
321 if config.doOptimalPhotometry:
322 # Add fields to hold the optimal aperture shape
323 # OptimalPhotometry case will fetch the aperture shape from here.
324 self.optimalShapeKey = afwTable.QuadrupoleKey.addFields(schema, schema.join(name, "OptimalShape"),
325 doc="Pre-seeing aperture used for "
326 "optimal GAaP photometry")
327 for scalingFactor in config.scalingFactors:
328 baseName = self.ConfigClass._getGaapResultName(scalingFactor, "Optimal", name)
329 docstring = f"GAaP Flux with optimal aperture after multiplying the seeing by {scalingFactor}"
330 measBase.FluxResultKey.addFields(schema, name=baseName, doc=docstring)
332 # Remove the prefix_ since FlagHandler prepends it
333 middleName = self.ConfigClass._getGaapResultName(scalingFactor, "Optimal")
334 flagDefs.add(schema.join(middleName, "flag_bigPsf"), "The Gaussianized PSF is "
335 "bigger than the aperture")
336 flagDefs.add(schema.join(middleName, "flag"), "Generic failure flag for this set of config "
337 "parameters. ")
339 if config.registerForApCorr:
340 for baseName in config.getAllGaapResultNames(name):
341 measBase.addApCorrName(baseName)
343 for scalingFactor in config.scalingFactors:
344 flagName = self.ConfigClass._getGaapResultName(scalingFactor, "flag_gaussianization")
345 flagDefs.add(flagName, "PSF Gaussianization failed when trying to scale by this factor.")
347 self.log = logging.getLogger(logName)
348 self.flagHandler = measBase.FlagHandler.addFields(schema, name, flagDefs)
349 self.EdgeFlagKey = schema.addField(schema.join(name, "flag_edge"), type="Flag",
350 doc="Source is too close to the edge")
351 self.NoPixelKey = schema.addField(schema.join(name, "flag_no_pixel"), type="Flag",
352 doc="No pixels in the footprint")
353 self._failKey = schema.addField(name + '_flag', type="Flag", doc="Set for any fatal failure")
355 self.psfMatchTask = config._modelPsfMatch.target(config=config._modelPsfMatch)
357 @staticmethod
358 def _computeKernelAcf(kernel: lsst.afw.math.Kernel) -> lsst.afw.image.Image: # noqa: F821
359 """Compute the auto-correlation function of ``kernel``.
361 Parameters
362 ----------
363 kernel : `~lsst.afw.math.Kernel`
364 The kernel for which auto-correlation function is to be computed.
366 Returns
367 -------
368 acfImage : `~lsst.afw.image.Image`
369 The two-dimensional auto-correlation function of ``kernel``.
370 """
371 kernelImage = afwImage.ImageD(kernel.getDimensions())
372 kernel.computeImage(kernelImage, False)
373 acfArray = scipy.signal.correlate2d(kernelImage.array, kernelImage.array, boundary='fill')
374 acfImage = afwImage.ImageD(acfArray)
375 return acfImage
377 @staticmethod
378 def _getFluxErrScaling(kernelAcf: lsst.afw.image.Image, # noqa: F821
379 aperShape: lsst.afw.geom.Quadrupole) -> float: # noqa: F821
380 """Calculate the value by which the standard error has to be scaled due
381 to noise correlations.
383 This calculates the correction to apply to the naively computed
384 `instFluxErr` to account for correlations in the pixel noise introduced
385 in the PSF-Gaussianization step.
386 This method performs the integral in Eq. A17 of Kuijken et al. (2015).
388 The returned value equals
389 :math:`\\int\\mathrm{d}x C^G(x) \\exp(-x^T Q^{-1}x/4)`
390 where :math: `Q` is ``aperShape`` and :math: `C^G(x)` is ``kernelAcf``.
392 Parameters
393 ----------
394 kernelAcf : `~lsst.afw.image.Image`
395 The auto-correlation function (ACF) of the PSF matching kernel.
396 aperShape : `~lsst.afw.geom.Quadrupole`
397 The shape parameter of the Gaussian function which was used to
398 measure GAaP flux.
400 Returns
401 -------
402 fluxErrScaling : `float`
403 The factor by which the standard error on GAaP flux must be scaled.
404 """
405 aperShapeX2 = aperShape.convolve(aperShape)
406 corrFlux = measBase.SdssShapeAlgorithm.computeFixedMomentsFlux(kernelAcf, aperShapeX2,
407 kernelAcf.getBBox().getCenter())
408 fluxErrScaling = (0.5*corrFlux.instFlux)**0.5
409 return fluxErrScaling
411 def _gaussianize(self, exposure: afwImage.Exposure, modelPsf: afwDetection.GaussianPsf,
412 measRecord: lsst.afw.table.SourceRecord) -> lsst.pipe.base.Struct: # noqa: F821
413 """Modify the ``exposure`` so that its PSF is a Gaussian.
415 Compute the convolution kernel to make the PSF same as ``modelPsf``
416 and return the Gaussianized exposure in a struct.
418 Parameters
419 ----------
420 exposure : `~lsst.afw.image.Exposure`
421 Original (full) exposure containing all the sources.
422 modelPsf : `~lsst.afw.detection.GaussianPsf`
423 Target PSF to which to match.
424 measRecord : `~lsst.afw.tabe.SourceRecord`
425 Record for the source to be measured.
427 Returns
428 -------
429 result : `~lsst.pipe.base.Struct`
430 ``result`` is the Struct returned by `modelPsfMatch` task. Notably,
431 it contains a ``psfMatchedExposure``, which is the exposure
432 containing the source, convolved to the target seeing and
433 ``psfMatchingKernel``, the kernel that ``exposure`` was convolved
434 by to obtain ``psfMatchedExposure``. Typically, the bounding box of
435 ``psfMatchedExposure`` is larger than that of the footprint.
436 """
437 footprint = measRecord.getFootprint()
438 bbox = footprint.getBBox()
440 # The kernelSize is guaranteed to be odd, say 2N+1 pixels (N=10 by
441 # default). The flux inside the footprint is smeared by N pixels on
442 # either side, which is region of interest. So grow the bounding box
443 # initially by N pixels on either side.
444 pixToGrow = self.config._modelPsfMatch.kernel.active.kernelSize//2
445 bbox.grow(pixToGrow)
447 # The bounding box may become too big and go out of bounds for sources
448 # near the edge. Clip the subExposure to the exposure's bounding box.
449 # Set the flag_edge marking that the bbox of the footprint could not
450 # be grown fully but do not set it as a failure.
451 if not exposure.getBBox().contains(bbox):
452 bbox.clip(exposure.getBBox())
453 measRecord.setFlag(self.EdgeFlagKey, True)
455 subExposure = exposure[bbox]
457 # The size parameter of the basis has to be set dynamically.
458 result = self.psfMatchTask.run(exposure=subExposure, center=measRecord.getCentroid(),
459 targetPsfModel=modelPsf,
460 basisSigmaGauss=[modelPsf.getSigma()])
461 # TODO: DM-27407 will re-Gaussianize the exposure to make the PSF even
462 # more Gaussian-like
464 # Do not let the variance plane be rescaled since we handle it
465 # carefully later using _getFluxScaling method
466 result.psfMatchedExposure.variance.array = subExposure.variance.array
467 return result
469 def _measureFlux(self, measRecord: lsst.afw.table.SourceRecord,
470 exposure: afwImage.Exposure, kernelAcf: afwImage.Image,
471 center: lsst.geom.Point2D, aperShape: afwGeom.Quadrupole,
472 baseName: str, fluxScaling: Optional[float] = None) -> None:
473 """Measure the flux and populate the record.
475 Parameters
476 ----------
477 measRecord : `~lsst.afw.table.SourceRecord`
478 Catalog record for the source being measured.
479 exposure : `~lsst.afw.image.Exposure`
480 Subexposure containing the deblended source being measured.
481 The PSF attached to it should nominally be an
482 `lsst.afw.Detection.GaussianPsf` object, but not enforced.
483 kernelAcf : `~lsst.afw.image.Image`
484 An image representating the auto-correlation function of the
485 PSF-matching kernel.
486 center : `~lsst.geom.Point2D`
487 The centroid position of the source being measured.
488 aperShape : `~lsst.afw.geom.Quadrupole`
489 The shape parameter of the post-seeing Gaussian aperture.
490 It should be a valid quadrupole if ``fluxScaling`` is specified.
491 baseName : `str`
492 The base name of the GAaP field.
493 fluxScaling : `float`, optional
494 The multiplication factor by which the measured flux has to be
495 scaled. If `None` or unspecified, the pre-factor in Eq. A16
496 of Kuijken et al. (2015) is computed and applied.
497 """
498 if fluxScaling is None:
499 # Calculate the pre-factor in Eq. A16 of Kuijken et al. (2015)
500 # to scale the flux. Include an extra factor of 0.5 to undo
501 # the normalization factor of 2 in `computeFixedMomentsFlux`.
502 try:
503 aperShape.normalize()
504 # Calculate the pre-seeing aperture.
505 preseeingShape = aperShape.convolve(exposure.getPsf().computeShape(center))
506 fluxScaling = 0.5*preseeingShape.getArea()/aperShape.getArea()
507 except (InvalidParameterError, ZeroDivisionError):
508 self._setFlag(measRecord, baseName, "bigPsf")
509 return
511 # Calculate the integral in Eq. A17 of Kuijken et al. (2015)
512 # ``fluxErrScaling`` contains the factors not captured by
513 # ``fluxScaling`` and `instFluxErr`. It is 1 theoretically
514 # if ``kernelAcf`` is a Dirac-delta function.
515 fluxErrScaling = self._getFluxErrScaling(kernelAcf, aperShape)
517 fluxResult = measBase.SdssShapeAlgorithm.computeFixedMomentsFlux(exposure.getMaskedImage(),
518 aperShape, center)
520 # Scale the quantities in fluxResult and copy result to record
521 fluxResult.instFlux *= fluxScaling
522 fluxResult.instFluxErr *= fluxScaling*fluxErrScaling
523 fluxResultKey = measBase.FluxResultKey(measRecord.schema[baseName])
524 fluxResultKey.set(measRecord, fluxResult)
526 def _gaussianizeAndMeasure(self, measRecord: lsst.afw.table.SourceRecord,
527 exposure: afwImage.Exposure,
528 center: lsst.geom.Point2D) -> None:
529 """Measure the properties of a source on a single image.
531 The image may be from a single epoch, or it may be a coadd.
533 Parameters
534 ----------
535 measRecord : `~lsst.afw.table.SourceRecord`
536 Record describing the object being measured. Previously-measured
537 quantities may be retrieved from here, and it will be updated
538 in-place with the outputs of this plugin.
539 exposure : `~lsst.afw.image.ExposureF`
540 The pixel data to be measured, together with the associated PSF,
541 WCS, etc. All other sources in the image should have been replaced
542 by noise according to deblender outputs.
543 center : `~lsst.geom.Point2D`
544 Centroid location of the source being measured.
546 Raises
547 ------
548 GaapConvolutionError
549 Raised if the PSF Gaussianization fails for any of the target PSFs.
550 lsst.meas.base.FatalAlgorithmError
551 Raised if the Exposure does not contain a PSF model.
552 NoPixelError
553 Raised if the footprint has no pixels.
555 Notes
556 -----
557 This method is the entry point to the mixin from the concrete derived
558 classes.
559 """
561 # Raise errors if the plugin would fail for this record for all
562 # scaling factors and sigmas.
563 if measRecord.getFootprint().getArea() == 0:
564 self._setFlag(measRecord, self.name, "no_pixel")
565 raise NoPixelError
567 if (psf := exposure.getPsf()) is None:
568 raise measBase.FatalAlgorithmError("No PSF in exposure")
570 psfSigma = psf.computeShape(center).getTraceRadius()
571 if not (psfSigma > 0): # This captures NaN and negative values.
572 errorCollection = {str(scalingFactor): measBase.MeasurementError("PSF size could not be measured")
573 for scalingFactor in self.config.scalingFactor}
574 raise GaapConvolutionError(errorCollection)
575 else:
576 errorCollection = dict()
578 wcs = exposure.getWcs()
580 for scalingFactor in self.config.scalingFactors:
581 targetSigma = scalingFactor*psfSigma
582 # If this target PSF is bound to fail for all apertures,
583 # set the flags and move on without PSF Gaussianization.
584 if self._isAllFailure(measRecord, scalingFactor, targetSigma):
585 continue
587 stampSize = self.config._modelPsfDimension
588 targetPsf = afwDetection.GaussianPsf(stampSize, stampSize, targetSigma)
589 try:
590 result = self._gaussianize(exposure, targetPsf, measRecord)
591 except Exception as error:
592 errorCollection[str(scalingFactor)] = error
593 continue
595 convolved = result.psfMatchedExposure
596 kernelAcf = self._computeKernelAcf(result.psfMatchingKernel)
598 measureFlux = partial(self._measureFlux, measRecord, convolved, kernelAcf, center)
599 # Computing shape is inexpensive and position-independent for a
600 # GaussianPsf
601 psfShape = targetPsf.computeShape(center)
603 if self.config.doPsfPhotometry:
604 baseName = self.ConfigClass._getGaapResultName(scalingFactor, "PsfFlux", self.name)
605 aperShape = psfShape
606 measureFlux(aperShape, baseName, fluxScaling=1)
608 if self.config.doOptimalPhotometry:
609 baseName = self.ConfigClass._getGaapResultName(scalingFactor, "Optimal", self.name)
610 optimalShape = measRecord.get(self.optimalShapeKey)
611 aperShape = afwGeom.Quadrupole(optimalShape.getParameterVector()
612 - psfShape.getParameterVector())
613 measureFlux(aperShape, baseName)
615 # Iterate over pre-defined circular apertures
616 for sigma in self.config.sigmas:
617 baseName = self.ConfigClass._getGaapResultName(scalingFactor, sigma, self.name)
618 if sigma <= targetSigma * wcs.getPixelScale(center).asArcseconds():
619 # Raise when the aperture is invalid
620 self._setFlag(measRecord, baseName, "bigPsf")
621 continue
623 intrinsicShape = afwGeom.Quadrupole(sigma**2, sigma**2, 0.0) # in sky coordinates
624 intrinsicShape.transformInPlace(wcs.linearizeSkyToPixel(center,
625 lsst.geom.arcseconds).getLinear())
626 aperShape = afwGeom.Quadrupole(intrinsicShape.getParameterVector()
627 - psfShape.getParameterVector())
628 measureFlux(aperShape, baseName)
630 # Raise GaapConvolutionError before exiting the plugin
631 # if the collection of errors is not empty
632 if errorCollection:
633 raise GaapConvolutionError(errorCollection)
635 @staticmethod
636 def _setFlag(measRecord, baseName, flagName=None):
637 """Set the GAaP flag determined by ``baseName`` and ``flagName``.
639 A convenience method to set {baseName}_flag_{flagName} to True.
640 This also automatically sets the generic {baseName}_flag to True.
641 To set the general plugin flag indicating measurement failure,
642 use _failKey directly.
644 Parameters
645 ----------
646 measRecord : `~lsst.afw.table.SourceRecord`
647 Record describing the source being measured.
648 baseName : `str`
649 The base name of the GAaP field for which the flag must be set.
650 flagName : `str`, optional
651 The name of the specific flag to set along with the general flag.
652 If unspecified, only the general flag corresponding to ``baseName``
653 is set. For now, the only value that can be specified is "bigPsf".
654 """
655 if flagName is not None:
656 specificFlagKey = measRecord.schema.join(baseName, f"flag_{flagName}")
657 measRecord.set(specificFlagKey, True)
658 genericFlagKey = measRecord.schema.join(baseName, "flag")
659 measRecord.set(genericFlagKey, True)
661 def _isAllFailure(self, measRecord, scalingFactor, targetSigma) -> bool:
662 """Check if all measurements would result in failure.
664 If all of the pre-seeing apertures are smaller than size of the
665 target PSF for the given ``scalingFactor``, then set the
666 `flag_bigPsf` for all fields corresponding to ``scalingFactor``
667 and move on instead of spending computational effort in
668 Gaussianizing the exposure.
670 Parameters
671 ----------
672 measRecord : `~lsst.afw.table.SourceRecord`
673 Record describing the source being measured.
674 scalingFactor : `float`
675 The multiplicative factor by which the seeing is scaled.
676 targetSigma : `float`
677 Sigma (in pixels) of the target circular Gaussian PSF.
679 Returns
680 -------
681 allFailure : `bool`
682 A boolean value indicating whether all measurements would fail.
684 Notes
685 ----
686 If doPsfPhotometry is set to True, then this will always return False.
687 """
688 if self.config.doPsfPhotometry:
689 return False
691 allFailure = targetSigma >= max(self.config.sigmas)
692 # If measurements would fail on all circular apertures, and if
693 # optimal elliptical aperture is used, check if that would also fail.
694 if self.config.doOptimalPhotometry and allFailure:
695 optimalShape = measRecord.get(self.optimalShapeKey)
696 aperShape = afwGeom.Quadrupole(optimalShape.getParameterVector()
697 - [targetSigma**2, targetSigma**2, 0.0])
698 allFailure = (aperShape.getIxx() <= 0) or (aperShape.getIyy() <= 0) or (aperShape.getArea() <= 0)
700 # Set all failure flags if allFailure is True.
701 if allFailure:
702 if self.config.doOptimalPhotometry:
703 baseName = self.ConfigClass._getGaapResultName(scalingFactor, "Optimal", self.name)
704 self._setFlag(measRecord, baseName, "bigPsf")
705 for sigma in self.config.sigmas:
706 baseName = self.ConfigClass._getGaapResultName(scalingFactor, sigma, self.name)
707 self._setFlag(measRecord, baseName, "bigPsf")
709 return allFailure
711 def fail(self, measRecord, error=None):
712 """Record a measurement failure.
714 This default implementation simply records the failure in the source
715 record and is inherited by the SingleFrameGaapFluxPlugin and
716 ForcedGaapFluxPlugin.
718 Parameters
719 ----------
720 measRecord : `lsst.afw.table.SourceRecord`
721 Catalog record for the source being measured.
722 error : `Exception`
723 Error causing failure, or `None`.
724 """
725 if error is not None:
726 center = measRecord.getCentroid()
727 self.log.error("Failed to solve for PSF matching kernel in GAaP for (%f, %f): %s",
728 center.getX(), center.getY(), error)
729 for scalingFactor in error.errorDict:
730 flagName = self.ConfigClass._getGaapResultName(scalingFactor, "flag_gaussianization",
731 self.name)
732 measRecord.set(flagName, True)
733 for sigma in self.config._sigmas:
734 baseName = self.ConfigClass._getGaapResultName(scalingFactor, sigma, self.name)
735 self._setFlag(measRecord, baseName)
736 else:
737 measRecord.set(self._failKey, True)
740class SingleFrameGaapFluxConfig(BaseGaapFluxConfig,
741 measBase.SingleFramePluginConfig):
742 """Config for SingleFrameGaapFluxPlugin."""
745@measBase.register(PLUGIN_NAME)
746class SingleFrameGaapFluxPlugin(BaseGaapFluxMixin, measBase.SingleFramePlugin):
747 """Gaussian Aperture and PSF photometry algorithm in single-frame mode.
749 Parameters
750 ----------
751 config : `GaapFluxConfig`
752 Plugin configuration.
753 name : `str`
754 Plugin name, for registering.
755 schema : `lsst.afw.table.Schema`
756 The schema for the measurement output catalog. New fields will be added
757 to hold measurements produced by this plugin.
758 metadata : `lsst.daf.base.PropertySet`
759 Plugin metadata that will be attached to the output catalog.
760 logName : `str`, optional
761 Name to use when logging errors. This will be provided by the
762 measurement framework.
764 Notes
765 -----
766 This plugin must be run in forced mode to produce consistent colors across
767 the different bandpasses.
768 """
769 ConfigClass = SingleFrameGaapFluxConfig
771 def __init__(self, config, name, schema, metadata, logName=None):
772 BaseGaapFluxMixin.__init__(self, config, name, schema, logName=logName)
773 measBase.SingleFramePlugin.__init__(self, config, name, schema, metadata, logName=logName)
775 @classmethod
776 def getExecutionOrder(cls) -> float:
777 # Docstring inherited
778 return cls.FLUX_ORDER
780 def measure(self, measRecord, exposure):
781 # Docstring inherited.
782 center = measRecord.getCentroid()
783 if self.config.doOptimalPhotometry:
784 # The adaptive shape is set to post-seeing aperture.
785 # Convolve with the PSF shape to obtain pre-seeing aperture.
786 # Refer to pg. 30-31 of Kuijken et al. (2015) for this heuristic.
787 # psfShape = measRecord.getPsfShape() # TODO: DM-30229
788 psfShape = afwTable.QuadrupoleKey(measRecord.schema["slot_PsfShape"]).get(measRecord)
789 optimalShape = measRecord.getShape().convolve(psfShape)
790 # Record the aperture used for optimal photometry
791 measRecord.set(self.optimalShapeKey, optimalShape)
792 self._gaussianizeAndMeasure(measRecord, exposure, center)
795class ForcedGaapFluxConfig(BaseGaapFluxConfig, measBase.ForcedPluginConfig):
796 """Config for ForcedGaapFluxPlugin."""
799@measBase.register(PLUGIN_NAME)
800class ForcedGaapFluxPlugin(BaseGaapFluxMixin, measBase.ForcedPlugin):
801 """Gaussian Aperture and PSF (GAaP) photometry plugin in forced mode.
803 This is the GAaP plugin to run for consistent colors across the bandpasses.
805 Parameters
806 ----------
807 config : `GaapFluxConfig`
808 Plugin configuration.
809 name : `str`
810 Plugin name, for registering.
811 schemaMapper : `lsst.afw.table.SchemaMapper`
812 A mapping from reference catalog fields to output catalog fields.
813 Output fields will be added to the output schema.
814 for the measurement output catalog. New fields will be added
815 to hold measurements produced by this plugin.
816 metadata : `lsst.daf.base.PropertySet`
817 Plugin metadata that will be attached to the output catalog.
818 logName : `str`, optional
819 Name to use when logging errors. This will be provided by the
820 measurement framework.
821 """
822 ConfigClass = ForcedGaapFluxConfig
824 def __init__(self, config, name, schemaMapper, metadata, logName=None):
825 schema = schemaMapper.editOutputSchema()
826 BaseGaapFluxMixin.__init__(self, config, name, schema, logName=logName)
827 measBase.ForcedPlugin.__init__(self, config, name, schemaMapper, metadata, logName=logName)
829 @classmethod
830 def getExecutionOrder(cls) -> float:
831 # Docstring inherited.
832 return cls.FLUX_ORDER
834 def measure(self, measRecord, exposure, refRecord, refWcs):
835 # Docstring inherited.
836 wcs = exposure.getWcs()
837 center = wcs.skyToPixel(refWcs.pixelToSky(refRecord.getCentroid()))
838 if self.config.doOptimalPhotometry:
839 # The adaptive shape is set to post-seeing aperture.
840 # Convolve it with the PSF shape to obtain pre-seeing aperture.
841 # Refer to pg. 30-31 of Kuijken et al. (2015) for this heuristic.
842 # psfShape = refRecord.getPsfShape() # TODO: DM-30229
843 psfShape = afwTable.QuadrupoleKey(refRecord.schema["slot_PsfShape"]).get(refRecord)
844 optimalShape = refRecord.getShape().convolve(psfShape)
845 if not (wcs == refWcs):
846 measFromSky = wcs.linearizeSkyToPixel(measRecord.getCentroid(), lsst.geom.radians)
847 skyFromRef = refWcs.linearizePixelToSky(refRecord.getCentroid(), lsst.geom.radians)
848 measFromRef = measFromSky*skyFromRef
849 optimalShape.transformInPlace(measFromRef.getLinear())
850 # Record the intrinsic aperture used for optimal photometry.
851 measRecord.set(self.optimalShapeKey, optimalShape)
852 self._gaussianizeAndMeasure(measRecord, exposure, center)