DirectMatchTask: add selection of science,ref sources

Selecting sources before matching makes the matching process easier.

python/lsst/meas/astrom/directMatch.py

@@ -4,7 +4,8 @@
 
 from lsst.pex.config import Config, Field, ConfigurableField
 from lsst.pipe.base import Task, Struct
-from lsst.meas.algorithms import LoadIndexedReferenceObjectsTask
+from lsst.meas.algorithms import (LoadIndexedReferenceObjectsTask, ScienceSourceSelectorTask,
+                                  ReferenceSourceSelectorTask)
 import lsst.afw.table as afwTable
 import lsst.afw.coord as afwCoord
 from lsst.afw.geom import arcseconds
@@ -14,6 +15,10 @@ class DirectMatchConfig(Config):
     """Configuration for DirectMatchTask"""
     refObjLoader = ConfigurableField(target=LoadIndexedReferenceObjectsTask, doc="Load reference objects")
     matchRadius = Field(dtype=float, default=0.25, doc="Matching radius, arcsec")
+    sourceSelection = ConfigurableField(target=ScienceSourceSelectorTask,
+                                        doc="Selection of science sources")
+    referenceSelection = ConfigurableField(target=ReferenceSourceSelectorTask,
+                                           doc="Selection of reference sources")
 
 
 class DirectMatchTask(Task):
@@ -77,6 +82,8 @@ def __init__(self, butler=None, refObjLoader=None, **kwargs):
             self.makeSubtask("refObjLoader", butler=butler)
         else:
             self.refObjLoader = refObjLoader
+        self.makeSubtask("sourceSelection")
+        self.makeSubtask("referenceSelection")
 
     def run(self, catalog, filterName=None):
         """!Load reference objects and match to them
@@ -88,11 +95,22 @@ def run(self, catalog, filterName=None):
         """
         circle = self.calculateCircle(catalog)
         matchMeta = self.refObjLoader.getMetadataCircle(circle.center, circle.radius, filterName)
+        sourceSelection = self.sourceSelection.selectSources(catalog)
+        if len(sourceSelection.sourceCat) == 0:
+            self.log.warn("No objects selected from %d objects in source catalog", len(catalog))
+            return Struct(matches=[], matchMeta=matchMeta)
         refData = self.refObjLoader.loadSkyCircle(circle.center, circle.radius, filterName)
-        matches = afwTable.matchRaDec(refData.refCat, catalog, self.config.matchRadius*arcseconds)
-        self.log.info("Matched %d from %d input and %d reference sources" %
-                      (len(matches), len(catalog), len(refData.refCat)))
-        return Struct(matches=matches, matchMeta=matchMeta)
+        refCat = refData.refCat
+        refSelection = self.referenceSelection.selectSources(refCat)
+        if len(refSelection.sourceCat) == 0:
+            self.log.warn("No objects selected from %d objects in reference catalog", len(refCat))
+        matches = afwTable.matchRaDec(refSelection.sourceCat, sourceSelection.sourceCat,
+                                      self.config.matchRadius*arcseconds)
+        self.log.info("Matched %d from %d/%d input and %d/%d reference sources" %
+                      (len(matches), len(sourceSelection.sourceCat), len(catalog),
+                       len(refSelection.sourceCat), len(refCat)))
+        return Struct(matches=matches, matchMeta=matchMeta, refCat=refCat, sourceSelection=sourceSelection,
+                      refSelection=refSelection)
 
     def calculateCircle(self, catalog):
         """!Calculate a circle enclosing the catalog

python/lsst/meas/astrom/ref_match.py

@@ -28,6 +28,7 @@
 import lsst.afw.math as afwMath
 import lsst.pex.config as pexConfig
 import lsst.pipe.base as pipeBase
+from lsst.meas.algorithms import ScienceSourceSelectorTask, ReferenceSourceSelectorTask
 from .matchOptimisticB import MatchOptimisticBTask
 from .display import displayAstrometry
 from . import makeMatchStatistics
@@ -46,6 +47,10 @@ class RefMatchConfig(pexConfig.Config):
         default=2,
         min=0,
     )
+    sourceSelection = pexConfig.ConfigurableField(target=ScienceSourceSelectorTask,
+                                                  doc="Selection of science sources")
+    referenceSelection = pexConfig.ConfigurableField(target=ReferenceSourceSelectorTask,
+                                                     doc="Selection of reference sources")
 
 # The following block adds links to this task from the Task Documentation page.
 ## \addtogroup LSST_task_documentation
@@ -74,6 +79,8 @@ def __init__(self, refObjLoader, schema=None, **kwargs):
         pipeBase.Task.__init__(self, **kwargs)
         self.refObjLoader = refObjLoader
         self.makeSubtask("matcher")
+        self.makeSubtask("sourceSelection")
+        self.makeSubtask("referenceSelection")
 
     @pipeBase.timeMethod
     def loadAndMatch(self, exposure, sourceCat):
@@ -95,12 +102,17 @@ def loadAndMatch(self, exposure, sourceCat):
 
         expMd = self._getExposureMetadata(exposure)
 
+        sourceSelection = self.sourceSelection.selectSources(sourceCat)
+
         loadRes = self.refObjLoader.loadPixelBox(
             bbox=expMd.bbox,
             wcs=expMd.wcs,
             filterName=expMd.filterName,
             calib=expMd.calib,
         )
+
+        refSelection = self.referenceSelection.selectSources(loadRes.refCat)
+
         matchMeta = self.refObjLoader.getMetadataBox(
             bbox=expMd.bbox,
             wcs=expMd.wcs,
@@ -109,8 +121,8 @@ def loadAndMatch(self, exposure, sourceCat):
         )
 
         matchRes = self.matcher.matchObjectsToSources(
-            refCat=loadRes.refCat,
-            sourceCat=sourceCat,
+            refCat=refSelection.sourceCat,
+            sourceCat=sourceSelection.sourceCat,
             wcs=expMd.wcs,
             refFluxField=loadRes.fluxField,
             match_tolerance=None,
@@ -125,8 +137,8 @@ def loadAndMatch(self, exposure, sourceCat):
         if debug.display:
             frame = int(debug.frame)
             displayAstrometry(
-                refCat=loadRes.refCat,
-                sourceCat=sourceCat,
+                refCat=refSelection.sourceCat,
+                sourceCat=sourceSelection.sourceCat,
                 matches=matchRes.matches,
                 exposure=exposure,
                 bbox=expMd.bbox,
@@ -136,6 +148,8 @@ def loadAndMatch(self, exposure, sourceCat):
 
         return pipeBase.Struct(
             refCat=loadRes.refCat,
+            refSelection=refSelection,
+            sourceSelection=sourceSelection,
             matches=matchRes.matches,
             matchMeta=matchMeta,
         )

tests/test_astrometryTask.py

@@ -197,6 +197,7 @@ def makeSourceCat(self, distortedWcs):
         sourceFluxKey = sourceSchema["slot_ApFlux_flux"].asKey()
         sourceFluxSigmaKey = sourceSchema["slot_ApFlux_fluxSigma"].asKey()
 
+        sourceCat.reserve(len(refCat))
         for refObj in refCat:
             src = sourceCat.addNew()
             src.set(sourceCentroidKey, refObj.get(refCentroidKey))