def testPersistence(self):
im = ExposureF(10, 10)
im.setPsf(self.psf)
self.assertEqual(im.getPsf(), self.psf)
with lsst.utils.tests.getTempFilePath(".fits") as tmpFile:
im.writeFits(tmpFile)
newIm = ExposureF(tmpFile)
self.assertEqual(newIm.getPsf(), im.getPsf())
def testPersistence(self):
for pgp in self.pgps:
assert cppLib.isPersistable(pgp)
im = ExposureF(10, 10)
im.setPsf(pgp)
self.assertEqual(im.getPsf(), pgp)
with lsst.utils.tests.getTempFilePath(".fits") as tmpFile:
im.writeFits(tmpFile)
newIm = ExposureF(tmpFile)
self.assertEqual(newIm.getPsf(), im.getPsf())
def readFits(cls, path):
"""Read an external detrended image and create an LSST Exposure object
from it.
Any significant processing (e.g. pixel interpolation) should probably
be done in a ExternalIsrTask instead of here so it can be done once and
saved, instead of being done every time the image is loaded.
THIS METHOD IS INCOMPLETE; IT MUST BE MODIFIED ACCORDING TO THE
FORMAT OF THE DATA BEING LOADED.
"""
directory, filename = os.path.split(path)
match = cls.EXTERNAL_REGEX.match(filename)
camera = cls.getCameraFromVisit(match.group("visit"))
# Customize the code below based on the camera determined above.
# To support more than one camera it may be useful to delegate
# to other methods that are specific to certain cameras.
# Read the actual image in from the given path using e.g. astropy,
# and use it to fill in various arrays below.
bbox = Box2I(Point2I(0, 0), Extent2I(..., ...)) # width, height
result = ExposureF(bbox)
# main image, as a [y, x] numpy.float32 array
result.image.array = ...
# variance image, as a [y, x] numpy.float32 array
result.variance.array = ...
# This example includes masking NaN pixels as NO_DATA and pixels above
# 1E5 counts as SAT. External information about where bad pixels
# should be preferred when available, and obviously that saturation
# threshold is just an example (saturation should actually be
# determined before flat-fielding, of course).
# Interpolating these bad pixels is handled by ExternalIsrTask.
noDataBitMask = result.mask.getPlaneBitMask("NO_DATA")
satBitMask = result.mask.getPlaneBitMask("SAT")
result.mask.array |= noDataBitMask * np.isnan(result.image.array)
result.mask.array |= satBitMask * (result.image.array > 1E5)
# If you have a better guess at the PSF, we can find a way to use it.
# But it'd be a good idea to at least put this in with a guess at the
# seeing (RMS in pixels).
result.setPsf(SingleGaussianPsf(seeingRMS))
# Add a guess for the WCS, in this case assuming it's in the FITS
# header of the first HDU. Need to have something here, even if it
# isn't very good (e.g. whatever comes from the telescope).
metadata = readMetadata(filename)
wcs = SkyWcs(metadata)
result.setWcs(wcs)
return result
def testMatchSingleGaussianPsf(self):
"""Test InstallGaussianPsfTask when the input exposure has a single Gaussian PSF."""
config = InstallGaussianPsfTask.ConfigClass()
task = InstallGaussianPsfTask(config=config)
for desWidth, desHeight, desSigma in (
(21, 23, 1.2),
(23, 25, 3.5),
):
exposure = ExposureF(100, 100)
inPsf = SingleGaussianPsf(desWidth, desHeight, desSigma)
exposure.setPsf(inPsf)
task.run(exposure=exposure)
self.assertTrue(exposure.hasPsf())
psf = exposure.getPsf()
psfIm = psf.computeImage()
self.assertEqual(psfIm.getWidth(), desWidth)
self.assertEqual(psfIm.getHeight(), desHeight)
self.assertAlmostEqual(psf.computeShape().getDeterminantRadius(), desSigma, delta=1e-3)
def testMatchSingleGaussianPsf(self):
"""Test InstallGaussianPsfTask when the input exposure has a single Gaussian PSF
"""
config = InstallGaussianPsfTask.ConfigClass()
task = InstallGaussianPsfTask(config=config)
for desWidth, desHeight, desSigma in (
(21, 23, 1.2),
(23, 25, 3.5),
):
exposure = ExposureF(100, 100)
inPsf = SingleGaussianPsf(desWidth, desHeight, desSigma)
exposure.setPsf(inPsf)
task.run(exposure=exposure)
self.assertTrue(exposure.hasPsf())
psf = exposure.getPsf()
psfIm = psf.computeImage()
self.assertEqual(psfIm.getWidth(), desWidth)
self.assertEqual(psfIm.getHeight(), desHeight)
self.assertAlmostEqual(psf.computeShape().getDeterminantRadius(), desSigma, delta=1e-3)
def testMatchDoubleGaussianPsf(self):
"""Test InstallGaussianPsfTask when the input exposure has a DoubleGaussian PSF."""
config = InstallGaussianPsfTask.ConfigClass()
task = InstallGaussianPsfTask(config=config)
for doubleGaussParms in (
# width, height, inner sigma, outer sigma, outer/inner peak amplitude
(21, 23, 1.2, 3.5, 0.02),
(23, 25, 3.5, 9.0, 0.02),
):
exposure = ExposureF(100, 100)
inPsf = DoubleGaussianPsf(*doubleGaussParms)
exposure.setPsf(inPsf)
desWidth, desHeight, innerSigma = doubleGaussParms[0:3]
task.run(exposure=exposure)
self.assertTrue(exposure.hasPsf())
psf = exposure.getPsf()
psfIm = psf.computeImage()
self.assertEqual(psfIm.getWidth(), desWidth)
self.assertEqual(psfIm.getHeight(), desHeight)
self.assertAlmostEqual(psf.computeShape().getDeterminantRadius(), innerSigma, delta=0.1)
def testMatchDoubleGaussianPsf(self):
"""Test InstallGaussianPsfTask when the input exposure has a DoubleGaussian PSF
"""
config = InstallGaussianPsfTask.ConfigClass()
task = InstallGaussianPsfTask(config=config)
for doubleGaussParms in (
# width, height, inner sigma, outer sigma, outer/inner peak amplitude
(21, 23, 1.2, 3.5, 0.02),
(23, 25, 3.5, 9.0, 0.02),
):
exposure = ExposureF(100, 100)
inPsf = DoubleGaussianPsf(*doubleGaussParms)
exposure.setPsf(inPsf)
desWidth, desHeight, innerSigma = doubleGaussParms[0:3]
task.run(exposure=exposure)
self.assertTrue(exposure.hasPsf())
psf = exposure.getPsf()
psfIm = psf.computeImage()
self.assertEqual(psfIm.getWidth(), desWidth)
self.assertEqual(psfIm.getHeight(), desHeight)
self.assertAlmostEqual(psf.computeShape().getDeterminantRadius(), innerSigma, delta=0.1)