lsst.meas.base  16.0-6-g4a515f9+1
forcedPhotCoadd.py
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1 #!/usr/bin/env python
2 #
3 # LSST Data Management System
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23 
24 import lsst.pex.config
25 import lsst.pipe.base
26 import lsst.coadd.utils
27 import lsst.afw.table
28 
29 from .forcedPhotImage import ForcedPhotImageConfig, ForcedPhotImageTask
30 
31 __all__ = ("ForcedPhotCoaddConfig", "ForcedPhotCoaddTask")
32 
33 
35  footprintDatasetName = lsst.pex.config.Field(
36  doc="Dataset (without coadd prefix) that should be used to obtain (Heavy)Footprints for sources. "
37  "Must have IDs that match those of the reference catalog."
38  "If None, Footprints will be generated by transforming the reference Footprints.",
39  dtype=str,
40  default="meas",
41  optional=True
42  )
43 
44  def setDefaults(self):
45  ForcedPhotImageTask.ConfigClass.setDefaults(self)
46  # Copy 'id' and 'parent' columns without renaming them; since these are
47  # the only IDs we have in coadd processing, there's no need to qualify
48  # them with 'object'.
49  self.measurement.copyColumns["id"] = "id"
50  self.measurement.copyColumns["parent"] = "parent"
51  self.references.removePatchOverlaps = False # see validate() for why
52  self.measurement.plugins.names |= ['base_InputCount', 'base_Variance']
53  self.measurement.plugins['base_PixelFlags'].masksFpAnywhere = ['CLIPPED', 'SENSOR_EDGE',
54  'REJECTED', 'INEXACT_PSF']
55  self.measurement.plugins['base_PixelFlags'].masksFpCenter = ['CLIPPED', 'SENSOR_EDGE',
56  'REJECTED', 'INEXACT_PSF']
57 
58  def validate(self):
59  ForcedPhotImageTask.ConfigClass.validate(self)
60  if (self.measurement.doReplaceWithNoise and self.footprintDatasetName is not None and
61  self.references.removePatchOverlaps):
62  raise ValueError("Cannot use removePatchOverlaps=True with deblended footprints, as parent "
63  "sources may be rejected while their children are not.")
64 
65 
71 
72 
73 class ForcedPhotCoaddRunner(lsst.pipe.base.ButlerInitializedTaskRunner):
74  """Get the psfCache setting into ForcedPhotCoaddTask"""
75  @staticmethod
76  def getTargetList(parsedCmd, **kwargs):
77  return lsst.pipe.base.ButlerInitializedTaskRunner.getTargetList(parsedCmd,
78  psfCache=parsedCmd.psfCache)
79 
80 
82  """!
83  A command-line driver for performing forced measurement on coadd images
84 
85  This task is a subclass of ForcedPhotImageTask which is specifically for doing forced
86  measurement on a coadd, using as a reference catalog detections which were made on overlapping
87  coadds (i.e. in other bands).
88 
89  The run method (inherited from ForcedPhotImageTask) takes a lsst.daf.persistence.ButlerDataRef
90  argument that corresponds to a coadd image. This is used to provide all the inputs and outputs
91  for the task:
92  - A "*Coadd_src" (e.g. "deepCoadd_src") dataset is used as the reference catalog. This not loaded
93  directly from the passed dataRef, however; only the patch and tract are used, while the filter
94  is set by the configuration for the references subtask (see CoaddSrcReferencesTask).
95  - A "*Coadd_calexp" (e.g. "deepCoadd_calexp") dataset is used as the measurement image. Note that
96  this means that ProcessCoaddTask must be run on an image before ForcedPhotCoaddTask, in order
97  to generate the "*Coadd_calexp" dataset.
98  - A "*Coadd_forced_src" (e.g. "deepCoadd_forced_src") dataset will be written with the output
99  measurement catalog.
100 
101  In addition to the run method, ForcedPhotCcdTask overrides several methods of ForcedPhotImageTask
102  to specialize it for coadd processing, including makeIdFactory() and fetchReferences(). None of these
103  should be called directly by the user, though it may be useful to override them further in subclasses.
104  """
105 
106  ConfigClass = ForcedPhotCoaddConfig
107  RunnerClass = lsst.pipe.base.ButlerInitializedTaskRunner
108  _DefaultName = "forcedPhotCoadd"
109  dataPrefix = "deepCoadd_"
110 
111  def getExposure(self, dataRef):
112  name = self.config.coaddName + "Coadd_calexp"
113  return dataRef.get(name) if dataRef.datasetExists(name) else None
114 
115  def makeIdFactory(self, dataRef):
116  """Create an object that generates globally unique source IDs from per-CCD IDs and the CCD ID.
117 
118  @param dataRef Data reference from butler. The "CoaddId_bits" and "CoaddId"
119  datasets are accessed. The data ID must have tract and patch keys.
120  """
121  # With the default configuration, this IdFactory doesn't do anything, because
122  # the IDs it generates are immediately overwritten by the ID from the reference
123  # catalog (since that's in config.measurement.copyColumns). But we create one here anyway, to
124  # allow us to revert back to the old behavior of generating new forced source IDs,
125  # just by renaming the ID in config.copyColumns to "object_id".
126  expBits = dataRef.get(self.config.coaddName + "CoaddId_bits")
127  expId = int(dataRef.get(self.config.coaddName + "CoaddId"))
128  return lsst.afw.table.IdFactory.makeSource(expId, 64 - expBits)
129 
130  def getExposureId(self, dataRef):
131  return int(dataRef.get(self.config.coaddName + "CoaddId"))
132 
133  def fetchReferences(self, dataRef, exposure):
134  """Return an iterable of reference sources which overlap the exposure
135 
136  @param dataRef Data reference from butler corresponding to the image to be measured;
137  should have tract, patch, and filter keys.
138  @param exposure lsst.afw.image.Exposure to be measured (not used by this implementation)
139 
140  All work is delegated to the references subtask; see CoaddSrcReferencesTask for information
141  about the default behavior.
142  """
143  skyMap = dataRef.get(self.dataPrefix + "skyMap", immediate=True)
144  tractInfo = skyMap[dataRef.dataId["tract"]]
145  patch = tuple(int(v) for v in dataRef.dataId["patch"].split(","))
146  patchInfo = tractInfo.getPatchInfo(patch)
147  references = lsst.afw.table.SourceCatalog(self.references.schema)
148  references.extend(self.references.fetchInPatches(dataRef, patchList=[patchInfo]))
149  return references
150 
151  def attachFootprints(self, sources, refCat, exposure, refWcs, dataRef):
152  """For coadd forced photometry, we use the deblended HeavyFootprints from the single-band
153  measurements of the same band - because we've guaranteed that the peaks (and hence child sources)
154  will be consistent across all bands before we get to measurement, this should yield reasonable
155  deblending for most sources. It's most likely limitation is that it will not provide good flux
156  upper limits for sources that were not detected in this band but were blended with sources that
157  were.
158  """
159  if self.config.footprintDatasetName is None:
160  return ForcedPhotImageTask.attachFootprints(self, sources, refCat, exposure, refWcs, dataRef)
161  self.log.info("Loading deblended footprints for sources from %s, %s" %
162  (self.config.footprintDatasetName, dataRef.dataId))
163  fpCat = dataRef.get("%sCoadd_%s" % (self.config.coaddName, self.config.footprintDatasetName),
164  immediate=True)
165  for refRecord, srcRecord in zip(refCat, sources):
166  fpRecord = fpCat.find(refRecord.getId())
167  if fpRecord is None:
168  raise LookupError("Cannot find Footprint for source %s; please check that %sCoadd_%s "
169  "IDs are compatible with reference source IDs" %
170  (srcRecord.getId(), self.config.coaddName,
171  self.config.footprintDatasetName))
172  srcRecord.setFootprint(fpRecord.getFootprint())
173 
174  @classmethod
175  def _makeArgumentParser(cls):
176  parser = lsst.pipe.base.ArgumentParser(name=cls._DefaultName)
177  parser.add_id_argument("--id", "deepCoadd_forced_src", help="data ID, with raw CCD keys + tract",
178  ContainerClass=lsst.coadd.utils.CoaddDataIdContainer)
179  parser.add_argument("--psfCache", type=int, default=100, help="Size of CoaddPsf cache")
180  return parser
A base class for command-line forced measurement drivers.
static std::shared_ptr< IdFactory > makeSource(RecordId expId, int reserved)
def attachFootprints(self, sources, refCat, exposure, refWcs, dataRef)
A command-line driver for performing forced measurement on coadd images.
Config class for forced measurement driver task.