lsst.pipe.tasks gc397daaa20+4bb0446bb2
warpAndPsfMatch.py
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2# LSST Data Management System
3# Copyright 2008, 2009, 2010, 2011, 2012 LSST Corporation.
4#
5# This product includes software developed by the
6# LSST Project (http://www.lsst.org/).
7#
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16# GNU General Public License for more details.
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22import lsst.pex.config as pexConfig
23import lsst.afw.math as afwMath
24import lsst.geom as geom
25import lsst.afw.geom as afwGeom
26import lsst.pipe.base as pipeBase
27from lsst.ip.diffim import ModelPsfMatchTask
28from lsst.meas.algorithms import WarpedPsf
29
30__all__ = ["WarpAndPsfMatchTask"]
31
32
33class WarpAndPsfMatchConfig(pexConfig.Config):
34 """Config for WarpAndPsfMatchTask
35 """
36 psfMatch = pexConfig.ConfigurableField(
37 target=ModelPsfMatchTask,
38 doc="PSF matching model to model task",
39 )
40 warp = pexConfig.ConfigField(
41 dtype=afwMath.Warper.ConfigClass,
42 doc="warper configuration",
43 )
44
45
46class WarpAndPsfMatchTask(pipeBase.Task):
47 """A task to warp and PSF-match an exposure
48 """
49 ConfigClass = WarpAndPsfMatchConfig
50
51 def __init__(self, *args, **kwargs):
52 pipeBase.Task.__init__(self, *args, **kwargs)
53 self.makeSubtask("psfMatch")
54 self.warper = afwMath.Warper.fromConfig(self.config.warp)
55
56 def run(self, exposure, wcs, modelPsf=None, maxBBox=None, destBBox=None,
57 makeDirect=True, makePsfMatched=False):
58 """Warp and optionally PSF-match exposure
59
60 Parameters
61 ----------
62 exposure : :cpp:class: `lsst::afw::image::Exposure`
63 Exposure to preprocess.
64 wcs : :cpp:class:`lsst::afw::image::Wcs`
65 Desired WCS of temporary images.
66 modelPsf : :cpp:class: `lsst::meas::algorithms::KernelPsf` or None
67 Target PSF to which to match.
68 maxBBox : :cpp:class:`lsst::afw::geom::Box2I` or None
69 Maximum allowed parent bbox of warped exposure.
70 If None then the warped exposure will be just big enough to contain all warped pixels;
71 if provided then the warped exposure may be smaller, and so missing some warped pixels;
72 ignored if destBBox is not None.
73 destBBox: :cpp:class: `lsst::afw::geom::Box2I` or None
74 Exact parent bbox of warped exposure.
75 If None then maxBBox is used to determine the bbox, otherwise maxBBox is ignored.
76 makeDirect : bool
77 Return an exposure that has been only warped?
78 makePsfMatched : bool
79 Return an exposure that has been warped and PSF-matched?
80
81 Returns
82 -------
83 An lsst.pipe.base.Struct with the following fields:
84
85 direct : :cpp:class:`lsst::afw::image::Exposure`
86 warped exposure
87 psfMatched : :cpp:class: `lsst::afw::image::Exposure`
88 warped and psf-Matched temporary exposure
89 """
90 if makePsfMatched and modelPsf is None:
91 raise RuntimeError("makePsfMatched=True, but no model PSF was provided")
92
93 if not makePsfMatched and not makeDirect:
94 self.log.warning("Neither makeDirect nor makePsfMatched requested")
95
96 # Warp PSF before overwriting exposure
97 xyTransform = afwGeom.makeWcsPairTransform(exposure.getWcs(), wcs)
98 psfWarped = WarpedPsf(exposure.getPsf(), xyTransform)
99
100 if makePsfMatched and maxBBox is not None:
101 # grow warped region to provide sufficient area for PSF-matching
102 pixToGrow = 2 * max(self.psfMatch.kConfig.sizeCellX,
103 self.psfMatch.kConfig.sizeCellY)
104 # replace with copy
105 maxBBox = geom.Box2I(maxBBox)
106 maxBBox.grow(pixToGrow)
107
108 with self.timer("warp"):
109 exposure = self.warper.warpExposure(wcs, exposure, maxBBox=maxBBox, destBBox=destBBox)
110 exposure.setPsf(psfWarped)
111
112 if makePsfMatched:
113 try:
114 exposurePsfMatched = self.psfMatch.run(exposure, modelPsf).psfMatchedExposure
115 except Exception as e:
116 exposurePsfMatched = None
117 self.log.info("Cannot PSF-Match: %s", e)
118
119 return pipeBase.Struct(
120 direct=exposure if makeDirect else None,
121 psfMatched=exposurePsfMatched if makePsfMatched else None
122 )
def run(self, exposure, wcs, modelPsf=None, maxBBox=None, destBBox=None, makeDirect=True, makePsfMatched=False)