lsst.synpipe  15.0-3-g11fe1a0+14
randomStarFakes.py
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1 from __future__ import print_function
2 from builtins import range
3 import lsst.afw.image
4 import lsst.afw.geom
5 import lsst.afw.math
6 import lsst.pex.config
7 from lsst.pipe.tasks.fakes import BaseFakeSourcesConfig, BaseFakeSourcesTask
8 
9 import lsst.synpipe.FakeSourceLib as fsl
10 import numpy as np
11 
12 
13 class RandomStarFakeSourcesConfig(BaseFakeSourcesConfig):
14  nStars = lsst.pex.config.Field(dtype=int, default=1,
15  doc="Number of stars to add")
16  magnitude = lsst.pex.config.Field(dtype=float, default=20.0,
17  doc="Magnitude of all stars to be added")
18  margin = lsst.pex.config.Field(dtype=int, default=None, optional=True,
19  doc="Size of margin at edge that should not be added")
20  seed = lsst.pex.config.Field(dtype=int, default=1,
21  doc="Seed for random number generator")
22 
23 
24 class RandomStarFakeSourcesTask(BaseFakeSourcesTask):
25  ConfigClass = RandomStarFakeSourcesConfig
26 
27  def __init__(self, **kwargs):
28  BaseFakeSourcesTask.__init__(self, **kwargs)
29  print("RNG seed:", self.config.seed)
30  self.rng = lsst.afw.math.Random(seed=self.config.seed)
31  self.npRand = np.random.RandomState(self.config.seed)
32 
33  def run(self, exposure, background):
34 
35  self.log.info("Adding fake random stars")
36  psf = exposure.getPsf()
37  psfBBox = psf.computeImage().getBBox()
38  margin = int(np.floor(max(psfBBox.getWidth(), psfBBox.getHeight())/2)) + 1
39  if self.config.margin is not None:
40  if self.config.margin < margin:
41  raise ValueError("margin is not large enough for PSF")
42  bboxI = exposure.getBBox(lsst.afw.image.PARENT)
43  bboxI.grow(-margin)
44  bboxD = lsst.afw.geom.BoxD(bboxI)
45  flux = exposure.getCalib().getFlux(self.config.magnitude)
46  md = exposure.getMetadata()
47  for i in range(self.config.nStars):
48  x = self.rng.flat(bboxD.getMinX(), bboxD.getMaxX())
49  y = self.rng.flat(bboxD.getMinY(), bboxD.getMaxY())
50  md.set("FAKE%d" % i, "%.3f, %.3f" % (x, y))
51  self.log.info("Adding fake at: %.1f,%.1f" % (x, y))
52  psfImage = psf.computeImage(lsst.afw.geom.Point2D(x, y))
53  psfImage *= flux
54 
55  psfMaskedImage = lsst.afw.image.MaskedImageF(psfImage.convertF())
56 
57  mask = psfMaskedImage.getMask()
58  mask.set(self.bitmask)
59 
60  # the line below would work if the subimage call worked in PARENT coordinates.
61  # Since it doesn't at present, we have to do the longer call below.
62  # subMaskedImage = exposure.getMaskedImage()[psfImage.getBBox(lsst.afw.image.PARENT)]
63  subMaskedImage = exposure.getMaskedImage().Factory(exposure.getMaskedImage(),
64  psfImage.getBBox(lsst.afw.image.PARENT),
65  lsst.afw.image.PARENT)
66  subMaskedImage += psfMaskedImage