Inheritance diagram for lsst.meas.algorithms.brightStarStamps.BrightStarStamp:

Public Member Functions
	factory (cls, stamp_im, metadata, idx, archive_element=None, minValidAnnulusFraction=0.0)

	measureAndNormalize (self, SpanSet annulus, StatisticsControl statsControl=StatisticsControl(), Property statsFlag=stringToStatisticsProperty("MEAN"), Collection[str] badMaskPlanes=("BAD", "SAT", "NO_DATA"))

Public Attributes
	stamp_im

	validAnnulusFraction

	minValidAnnulusFraction

	annularFlux

Static Public Attributes
MaskedImageF	stamp_im

float	gaiaGMag

int	gaiaId

Point2I	position

Persistable	archive_element = None

float	annularFlux = None

float	minValidAnnulusFraction = 0.0

float	validAnnulusFraction = None

int	optimalInnerRadius = None

int	optimalOuterRadius = None

Detailed Description

Single stamp centered on a bright star, normalized by its annularFlux.

Parameters
----------
stamp_im : `~lsst.afw.image.MaskedImage`
    Pixel data for this postage stamp
gaiaGMag : `float`
    Gaia G magnitude for the object in this stamp
gaiaId : `int`
    Gaia object identifier
position : `~lsst.geom.Point2I`
    Origin of the stamps in its origin exposure (pixels)
archive_element : `~lsst.afw.table.io.Persistable` or None, optional
    Archive element (e.g. Transform or WCS) associated with this stamp.
annularFlux : `float` or None, optional
    Flux in an annulus around the object

Definition at line 45 of file brightStarStamps.py.

Member Function Documentation

◆ factory()

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.factory	(	cls,
		stamp_im,
		metadata,
		idx,
		archive_element = None,
		minValidAnnulusFraction = 0.0 )

This method is needed to service the FITS reader. We need a standard
interface to construct objects like this. Parameters needed to
construct this object are passed in via a metadata dictionary and then
passed to the constructor of this class.  This particular factory
method requires keys: G_MAGS, GAIA_IDS, and ANNULAR_FLUXES. They should
each point to lists of values.

Parameters
----------
stamp_im : `~lsst.afw.image.MaskedImage`
    Pixel data to pass to the constructor
metadata : `dict`
    Dictionary containing the information
    needed by the constructor.
idx : `int`
    Index into the lists in ``metadata``
archive_element : `~lsst.afw.table.io.Persistable` or None, optional
    Archive element (e.g. Transform or WCS) associated with this stamp.
minValidAnnulusFraction : `float`, optional
    The fraction of valid pixels within the normalization annulus of a
    star.

Returns
-------
brightstarstamp : `BrightStarStamp`
    An instance of this class

Reimplemented from lsst.meas.algorithms.stamps.AbstractStamp.

Definition at line 76 of file brightStarStamps.py.

    def factory(cls, stamp_im, metadata, idx, archive_element=None, minValidAnnulusFraction=0.0):
        """This method is needed to service the FITS reader. We need a standard
        interface to construct objects like this. Parameters needed to
        construct this object are passed in via a metadata dictionary and then
        passed to the constructor of this class.  This particular factory
        method requires keys: G_MAGS, GAIA_IDS, and ANNULAR_FLUXES. They should
        each point to lists of values.
 
        Parameters
        ----------
        stamp_im : `~lsst.afw.image.MaskedImage`
            Pixel data to pass to the constructor
        metadata : `dict`
            Dictionary containing the information
            needed by the constructor.
        idx : `int`
            Index into the lists in ``metadata``
        archive_element : `~lsst.afw.table.io.Persistable` or None, optional
            Archive element (e.g. Transform or WCS) associated with this stamp.
        minValidAnnulusFraction : `float`, optional
            The fraction of valid pixels within the normalization annulus of a
            star.
 
        Returns
        -------
        brightstarstamp : `BrightStarStamp`
            An instance of this class
        """
        if "X0S" in metadata and "Y0S" in metadata:
            x0 = metadata.getArray("X0S")[idx]
            y0 = metadata.getArray("Y0S")[idx]
            position = Point2I(x0, y0)
        else:
            position = None
        return cls(
            stamp_im=stamp_im,
            gaiaGMag=metadata.getArray("G_MAGS")[idx],
            gaiaId=metadata.getArray("GAIA_IDS")[idx],
            position=position,
            archive_element=archive_element,
            annularFlux=metadata.getArray("ANNULAR_FLUXES")[idx],
            minValidAnnulusFraction=minValidAnnulusFraction,
            validAnnulusFraction=metadata.getArray("VALID_PIXELS_FRACTION")[idx],
        )
 

◆ measureAndNormalize()

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.measureAndNormalize	(		self,
		SpanSet	annulus,
		StatisticsControl	statsControl = StatisticsControl(),
		Property	statsFlag = stringToStatisticsProperty("MEAN"),
		Collection[str]	badMaskPlanes = ("BAD", "SAT", "NO_DATA") )

Compute "annularFlux", the integrated flux within an annulus
around an object's center, and normalize it.

Since the center of bright stars are saturated and/or heavily affected
by ghosts, we measure their flux in an annulus with a large enough
inner radius to avoid the most severe ghosts and contain enough
non-saturated pixels.

Parameters
----------
annulus : `~lsst.afw.geom.spanSet.SpanSet`
    SpanSet containing the annulus to use for normalization.
statsControl : `~lsst.afw.math.statistics.StatisticsControl`, optional
    StatisticsControl to be used when computing flux over all pixels
    within the annulus.
statsFlag : `~lsst.afw.math.statistics.Property`, optional
    statsFlag to be passed on to ``afwMath.makeStatistics`` to compute
    annularFlux. Defaults to a simple MEAN.
badMaskPlanes : `collections.abc.Collection` [`str`]
    Collection of mask planes to ignore when computing annularFlux.

Definition at line 121 of file brightStarStamps.py.

    ):
        """Compute "annularFlux", the integrated flux within an annulus
        around an object's center, and normalize it.
 
        Since the center of bright stars are saturated and/or heavily affected
        by ghosts, we measure their flux in an annulus with a large enough
        inner radius to avoid the most severe ghosts and contain enough
        non-saturated pixels.
 
        Parameters
        ----------
        annulus : `~lsst.afw.geom.spanSet.SpanSet`
            SpanSet containing the annulus to use for normalization.
        statsControl : `~lsst.afw.math.statistics.StatisticsControl`, optional
            StatisticsControl to be used when computing flux over all pixels
            within the annulus.
        statsFlag : `~lsst.afw.math.statistics.Property`, optional
            statsFlag to be passed on to ``afwMath.makeStatistics`` to compute
            annularFlux. Defaults to a simple MEAN.
        badMaskPlanes : `collections.abc.Collection` [`str`]
            Collection of mask planes to ignore when computing annularFlux.
        """
        stampSize = self.stamp_im.getDimensions()
        # Create image: science pixel values within annulus, NO_DATA elsewhere
        maskPlaneDict = self.stamp_im.mask.getMaskPlaneDict()
        annulusImage = MaskedImageF(stampSize, planeDict=maskPlaneDict)
        annulusMask = annulusImage.mask
        annulusMask.array[:] = 2 ** maskPlaneDict["NO_DATA"]
        annulus.copyMaskedImage(self.stamp_im, annulusImage)
        # Set mask planes to be ignored.
        andMask = reduce(ior, (annulusMask.getPlaneBitMask(bm) for bm in badMaskPlanes))
        statsControl.setAndMask(andMask)
 
        annulusStat = makeStatistics(annulusImage, statsFlag, statsControl)
        # Determine the number of valid (unmasked) pixels within the annulus.
        unMasked = annulusMask.array.size - np.count_nonzero(annulusMask.array)
        self.validAnnulusFraction = unMasked / annulus.getArea()
        logger.info(
            "The Star's annulus contains %s valid pixels and the annulus itself contains %s pixels.",
            unMasked,
            annulus.getArea(),
        )
        if unMasked > (annulus.getArea() * self.minValidAnnulusFraction):
            # Compute annularFlux.
            self.annularFlux = annulusStat.getValue()
            logger.info("Annular flux is: %s", self.annularFlux)
        else:
            raise RuntimeError(
                f"Less than {self.minValidAnnulusFraction * 100}% of pixels within the annulus are valid."
            )
        if np.isnan(self.annularFlux):
            raise RuntimeError("Annular flux computation failed, likely because there are no valid pixels.")
        if self.annularFlux < 0:
            raise RuntimeError("The annular flux is negative. The stamp can not be normalized!")
        # Normalize stamps.
        self.stamp_im.image.array /= self.annularFlux
        return None
 
 

Member Data Documentation

◆ annularFlux [1/2]

float lsst.meas.algorithms.brightStarStamps.BrightStarStamp.annularFlux = None

static

Definition at line 69 of file brightStarStamps.py.

◆ annularFlux [2/2]

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.annularFlux

Definition at line 171 of file brightStarStamps.py.

◆ archive_element

Persistable lsst.meas.algorithms.brightStarStamps.BrightStarStamp.archive_element = None

static

Definition at line 68 of file brightStarStamps.py.

◆ gaiaGMag

float lsst.meas.algorithms.brightStarStamps.BrightStarStamp.gaiaGMag

static

Definition at line 65 of file brightStarStamps.py.

◆ gaiaId

int lsst.meas.algorithms.brightStarStamps.BrightStarStamp.gaiaId

static

Definition at line 66 of file brightStarStamps.py.

◆ minValidAnnulusFraction [1/2]

float lsst.meas.algorithms.brightStarStamps.BrightStarStamp.minValidAnnulusFraction = 0.0

static

Definition at line 70 of file brightStarStamps.py.

◆ minValidAnnulusFraction [2/2]

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.minValidAnnulusFraction

Definition at line 169 of file brightStarStamps.py.

◆ optimalInnerRadius

int lsst.meas.algorithms.brightStarStamps.BrightStarStamp.optimalInnerRadius = None

static

Definition at line 72 of file brightStarStamps.py.

◆ optimalOuterRadius

int lsst.meas.algorithms.brightStarStamps.BrightStarStamp.optimalOuterRadius = None

static

Definition at line 73 of file brightStarStamps.py.

◆ position

Point2I lsst.meas.algorithms.brightStarStamps.BrightStarStamp.position

static

Definition at line 67 of file brightStarStamps.py.

◆ stamp_im [1/2]

MaskedImageF lsst.meas.algorithms.brightStarStamps.BrightStarStamp.stamp_im

static

Definition at line 64 of file brightStarStamps.py.

◆ stamp_im [2/2]

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.stamp_im

Definition at line 155 of file brightStarStamps.py.

◆ validAnnulusFraction [1/2]

float lsst.meas.algorithms.brightStarStamps.BrightStarStamp.validAnnulusFraction = None

static

Definition at line 71 of file brightStarStamps.py.

◆ validAnnulusFraction [2/2]

lsst.meas.algorithms.brightStarStamps.BrightStarStamp.validAnnulusFraction

Definition at line 163 of file brightStarStamps.py.

The documentation for this class was generated from the following file:

/j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/meas_algorithms/ge6526c86ff+3a7c1ac5f1/python/lsst/meas/algorithms/brightStarStamps.py

Public Member Functions

Public Attributes

Static Public Attributes

Detailed Description

Member Function Documentation

◆ factory()

◆ measureAndNormalize()

Member Data Documentation

◆ annularFlux [1/2]

◆ annularFlux [2/2]

◆ archive_element

◆ gaiaGMag

◆ gaiaId

◆ minValidAnnulusFraction [1/2]

◆ minValidAnnulusFraction [2/2]

◆ optimalInnerRadius

◆ optimalOuterRadius

◆ position

◆ stamp_im [1/2]

◆ stamp_im [2/2]

◆ validAnnulusFraction [1/2]

◆ validAnnulusFraction [2/2]