22 from __future__
import absolute_import, division, print_function
24 __all__ = [
"AstrometryConfig",
"AstrometryTask"]
26 from builtins
import range
28 import lsst.pex.config
as pexConfig
29 import lsst.pipe.base
as pipeBase
30 import lsst.afw.geom
as afwGeom
31 from .ref_match
import RefMatchTask, RefMatchConfig
32 from .fitTanSipWcs
import FitTanSipWcsTask
33 from .display
import displayAstrometry
37 wcsFitter = pexConfig.ConfigurableField(
38 target=FitTanSipWcsTask,
41 forceKnownWcs = pexConfig.Field(
43 doc=
"If True then load reference objects and match sources but do not fit a WCS; " +
44 " this simply controls whether 'run' calls 'solve' or 'loadAndMatch'",
47 maxIter = pexConfig.RangeField(
48 doc=
"maximum number of iterations of match sources and fit WCS" +
49 "ignored if not fitting a WCS",
54 minMatchDistanceArcSec = pexConfig.RangeField(
55 doc=
"the match distance below which further iteration is pointless (arcsec); " 56 "ignored if not fitting a WCS",
72 """!Match an input source catalog with objects from a reference catalog and solve for the WCS 74 @anchor AstrometryTask_ 76 @section meas_astrom_astrometry_Contents Contents 78 - @ref meas_astrom_astrometry_Purpose 79 - @ref meas_astrom_astrometry_Initialize 80 - @ref meas_astrom_astrometry_IO 81 - @ref meas_astrom_astrometry_Config 82 - @ref meas_astrom_astrometry_Example 83 - @ref meas_astrom_astrometry_Debug 85 @section meas_astrom_astrometry_Purpose Description 87 Match input sourceCat with a reference catalog and solve for the Wcs 89 There are three steps, each performed by different subtasks: 90 - Find position reference stars that overlap the exposure 91 - Match sourceCat to position reference stars 92 - Fit a WCS based on the matches 94 @section meas_astrom_astrometry_Initialize Task initialisation 98 @section meas_astrom_astrometry_IO Invoking the Task 102 @copydoc loadAndMatch 104 @section meas_astrom_astrometry_Config Configuration parameters 106 See @ref AstrometryConfig 108 @section meas_astrom_astrometry_Example A complete example of using AstrometryTask 110 See \ref pipe_tasks_photocal_Example. 112 @section meas_astrom_astrometry_Debug Debug variables 114 The @link lsst.pipe.base.cmdLineTask.CmdLineTask command line task@endlink interface supports a 115 flag @c -d to import @b debug.py from your @c PYTHONPATH; see @ref baseDebug for more about 118 The available variables in AstrometryTask are: 120 <DT> @c display (bool) 121 <DD> If True display information at three stages: after finding reference objects, 122 after matching sources to reference objects, and after fitting the WCS; defaults to False 124 <DD> ds9 frame to use to display the reference objects; the next two frames are used 125 to display the match list and the results of the final WCS; defaults to 0 128 To investigate the @ref meas_astrom_astrometry_Debug, put something like 132 debug = lsstDebug.getInfo(name) # N.b. lsstDebug.Info(name) would call us recursively 133 if name == "lsst.meas.astrom.astrometry": 138 lsstDebug.Info = DebugInfo 140 into your debug.py file and run this task with the @c --debug flag. 142 ConfigClass = AstrometryConfig
143 _DefaultName =
"astrometricSolver" 145 def __init__(self, refObjLoader, schema=None, **kwargs):
146 """!Construct an AstrometryTask 148 @param[in] refObjLoader A reference object loader object 149 @param[in] schema ignored; available for compatibility with an older astrometry task 150 @param[in] kwargs additional keyword arguments for pipe_base Task.\_\_init\_\_ 152 RefMatchTask.__init__(self, refObjLoader, schema=schema, **kwargs)
154 if schema
is not None:
155 self.
usedKey = schema.addField(
"calib_astrometryUsed", type=
"Flag",
156 doc=
"set if source was used in astrometric calibration")
160 self.makeSubtask(
"wcsFitter")
163 def run(self, sourceCat, exposure):
164 """!Load reference objects, match sources and optionally fit a WCS 166 This is a thin layer around solve or loadAndMatch, depending on config.forceKnownWcs 168 @param[in,out] exposure exposure whose WCS is to be fit 169 The following are read only: 171 - calib (may be absent) 172 - filter (may be unset) 173 - detector (if wcs is pure tangent; may be absent) 174 The following are updated: 175 - wcs (the initial value is used as an initial guess, and is required) 176 @param[in] sourceCat catalog of sources detected on the exposure (an lsst.afw.table.SourceCatalog) 177 @return an lsst.pipe.base.Struct with these fields: 178 - refCat reference object catalog of objects that overlap the exposure (with some margin) 179 (an lsst::afw::table::SimpleCatalog) 180 - matches astrometric matches, a list of lsst.afw.table.ReferenceMatch 181 - scatterOnSky median on-sky separation between reference objects and sources in "matches" 182 (an lsst.afw.geom.Angle), or None if config.forceKnownWcs True 183 - matchMeta metadata needed to unpersist matches (an lsst.daf.base.PropertyList) 185 if self.config.forceKnownWcs:
186 res = self.
loadAndMatch(exposure=exposure, sourceCat=sourceCat)
187 res.scatterOnSky =
None 189 res = self.
solve(exposure=exposure, sourceCat=sourceCat)
193 def solve(self, exposure, sourceCat):
194 """!Load reference objects overlapping an exposure, match to sources and fit a WCS 196 @return an lsst.pipe.base.Struct with these fields: 197 - refCat reference object catalog of objects that overlap the exposure (with some margin) 198 (an lsst::afw::table::SimpleCatalog) 199 - matches astrometric matches, a list of lsst.afw.table.ReferenceMatch 200 - scatterOnSky median on-sky separation between reference objects and sources in "matches" 201 (an lsst.afw.geom.Angle) 202 - matchMeta metadata needed to unpersist matches (an lsst.daf.base.PropertyList) 204 @note ignores config.forceKnownWcs 207 debug = lsstDebug.Info(__name__)
214 filterName=expMd.filterName,
220 filterName=expMd.filterName,
225 frame = int(debug.frame)
227 refCat=loadRes.refCat,
232 title=
"Reference catalog",
237 match_tolerance =
None 238 for i
in range(self.config.maxIter):
242 refCat=loadRes.refCat,
244 refFluxField=loadRes.fluxField,
248 match_tolerance=match_tolerance,
250 except Exception
as e:
253 self.log.info(
"Fit WCS iter %d failed; using previous iteration: %s" % (iterNum, e))
259 match_tolerance = tryRes.match_tolerance
262 "Match and fit WCS iteration %d: found %d matches with scatter = %0.3f +- %0.3f arcsec; " 263 "max match distance = %0.3f arcsec",
264 iterNum, len(tryRes.matches), tryMatchDist.distMean.asArcseconds(),
265 tryMatchDist.distStdDev.asArcseconds(), tryMatchDist.maxMatchDist.asArcseconds())
267 maxMatchDist = tryMatchDist.maxMatchDist
270 if maxMatchDist.asArcseconds() < self.config.minMatchDistanceArcSec:
272 "Max match distance = %0.3f arcsec < %0.3f = config.minMatchDistanceArcSec; " 273 "that's good enough",
274 maxMatchDist.asArcseconds(), self.config.minMatchDistanceArcSec)
276 match_tolerance.maxMatchDist = maxMatchDist
279 "Matched and fit WCS in %d iterations; " 280 "found %d matches with scatter = %0.3f +- %0.3f arcsec" %
281 (iterNum, len(tryRes.matches), tryMatchDist.distMean.asArcseconds(),
282 tryMatchDist.distStdDev.asArcseconds()))
284 for m
in res.matches:
286 m.second.set(self.
usedKey,
True)
287 exposure.setWcs(res.wcs)
289 return pipeBase.Struct(
290 refCat=loadRes.refCat,
292 scatterOnSky=res.scatterOnSky,
297 def _matchAndFitWcs(self, refCat, sourceCat, refFluxField, bbox, wcs, match_tolerance,
299 """!Match sources to reference objects and fit a WCS 301 @param[in] refCat catalog of reference objects 302 @param[in] sourceCat catalog of sources detected on the exposure (an lsst.afw.table.SourceCatalog) 303 @param[in] refFluxField field of refCat to use for flux 304 @param[in] bbox bounding box of exposure (an lsst.afw.geom.Box2I) 305 @param[in] wcs initial guess for WCS of exposure (an lsst.afw.image.Wcs) 306 @param[in] match_tolerance a MatchTolerance object (or None) specifying 307 internal tolerances to the matcher. See the MatchTolerance 308 definition in the respective matcher for the class definition. 309 @param[in] exposure exposure whose WCS is to be fit, or None; used only for the debug display 311 @return an lsst.pipe.base.Struct with these fields: 312 - matches astrometric matches, a list of lsst.afw.table.ReferenceMatch 313 - wcs the fit WCS (an lsst.afw.image.Wcs) 314 - scatterOnSky median on-sky separation between reference objects and sources in "matches" 315 (an lsst.afw.geom.Angle) 318 debug = lsstDebug.Info(__name__)
319 matchRes = self.matcher.matchObjectsToSources(
323 refFluxField=refFluxField,
324 match_tolerance=match_tolerance,
326 self.log.debug(
"Found %s matches", len(matchRes.matches))
328 frame = int(debug.frame)
331 sourceCat=matchRes.usableSourceCat,
332 matches=matchRes.matches,
339 self.log.debug(
"Fitting WCS")
340 fitRes = self.wcsFitter.fitWcs(
341 matches=matchRes.matches,
349 scatterOnSky = fitRes.scatterOnSky
351 frame = int(debug.frame)
354 sourceCat=matchRes.usableSourceCat,
355 matches=matchRes.matches,
359 title=
"Fit TAN-SIP WCS",
362 return pipeBase.Struct(
363 matches=matchRes.matches,
365 scatterOnSky=scatterOnSky,
366 match_tolerance=matchRes.match_tolerance,
def _matchAndFitWcs(self, refCat, sourceCat, refFluxField, bbox, wcs, match_tolerance, exposure=None)
Match sources to reference objects and fit a WCS.
def solve(self, exposure, sourceCat)
Load reference objects overlapping an exposure, match to sources and fit a WCS.
def _computeMatchStatsOnSky(self, matchList)
def _getExposureMetadata(self, exposure)
Extract metadata from an exposure.
def run(self, sourceCat, exposure)
Load reference objects, match sources and optionally fit a WCS.
Match an input source catalog with objects from a reference catalog.
def __init__(self, refObjLoader, schema=None, kwargs)
Construct an AstrometryTask.
def displayAstrometry(refCat=None, sourceCat=None, distortedCentroidKey=None, bbox=None, exposure=None, matches=None, frame=1, title="", pause=True)
def loadAndMatch(self, exposure, sourceCat)
Load reference objects overlapping an exposure and match to sources detected on that exposure...
Match an input source catalog with objects from a reference catalog and solve for the WCS...