lsst::afw::detection::Footprint Class Reference

Class to describe the properties of a detected object from an image. More...

#include <Footprint.h>

Inheritance diagram for lsst::afw::detection::Footprint:

Public Member Functions
	Footprint (std::shared_ptr< geom::SpanSet > inputSpans, lsst::geom::Box2I const &region=lsst::geom::Box2I())
	Constructor for Footprint object.
	Footprint (std::shared_ptr< geom::SpanSet > inputSpans, afw::table::Schema const &peakSchema, lsst::geom::Box2I const &region=lsst::geom::Box2I())
	Constructor for the Footprint object.
	Footprint ()
	Constructor of a empty Footprint object.
	Footprint (Footprint const &other)=default
	Footprint (Footprint &&)=default
Footprint &	operator= (Footprint const &other)=default
Footprint &	operator= (Footprint &&)=default
	~Footprint () override=default
virtual bool	isHeavy () const
	Indicates if this object is a HeavyFootprint.
std::shared_ptr< geom::SpanSet >	getSpans () const
	Return a shared pointer to the SpanSet.
void	setSpans (std::shared_ptr< geom::SpanSet > otherSpanSet)
	Sets the shared pointer to the SpanSet in the Footprint.
PeakCatalog &	getPeaks ()
	Return the Peaks contained in this Footprint.
const PeakCatalog &	getPeaks () const
std::shared_ptr< PeakRecord >	addPeak (float fx, float fy, float value)
	Convenience function to add a peak.
void	sortPeaks (afw::table::Key< float > const &key=afw::table::Key< float >())
	Sort Peaks from most positive value to most negative.
void	setPeakSchema (afw::table::Schema const &peakSchema)
	Set the Schema used by the PeakCatalog (will throw if PeakCatalog is not empty).
void	setPeakCatalog (PeakCatalog const &otherPeaks)
	Set the peakCatalog to a copy of the supplied catalog.
std::size_t	getArea () const
	Return the number of pixels in this Footprint.
lsst::geom::Point2D	getCentroid () const
	Return the Footprint's centroid.
geom::ellipses::Quadrupole	getShape () const
	Return the Footprint's shape (interpreted as an ellipse)
void	shift (int dx, int dy)
	Shift a Footprint by (dx, dy)
void	shift (lsst::geom::ExtentI const &d)
	Shift a Footprint by a given extent.
lsst::geom::Box2I	getBBox () const
	Return the Footprint's bounding box.
lsst::geom::Box2I	getRegion () const
	Return the corners of the MaskedImage the footprints live in.
void	setRegion (lsst::geom::Box2I const &region)
	Set the corners of the MaskedImage wherein the footprints dwell.
void	clipTo (lsst::geom::Box2I const &bbox)
	Clip the Footprint such that all values lie inside the supplied Bounding Box.
bool	contains (lsst::geom::Point2I const &pix) const
	Tests if a pixel postion falls inside the Footprint.
std::shared_ptr< Footprint >	transform (std::shared_ptr< geom::SkyWcs > source, std::shared_ptr< geom::SkyWcs > target, lsst::geom::Box2I const &region, bool doClip=true) const
	Transform the footprint from one WCS to another.
std::shared_ptr< Footprint >	transform (lsst::geom::LinearTransform const &t, lsst::geom::Box2I const &region, bool doClip=true) const
	Return a new Footprint whose pixels are the product of applying the specified transformation.
std::shared_ptr< Footprint >	transform (lsst::geom::AffineTransform const &t, lsst::geom::Box2I const &region, bool doClip=true) const
	Return a new Footprint whose pixels are the product of applying the specified transformation.
std::shared_ptr< Footprint >	transform (geom::TransformPoint2ToPoint2 const &t, lsst::geom::Box2I const &region, bool doClip=true) const
	Return a new Footprint whose pixels are the product of applying the specified transformation.
bool	isPersistable () const noexcept override
	Report if this object is persistable.
void	dilate (int r, geom::Stencil s=geom::Stencil::CIRCLE)
	Dilate the Footprint with a defined kernel.
void	dilate (geom::SpanSet const &other)
	Dilate the Footprint with a defined kernel.
void	erode (int r, geom::Stencil s=geom::Stencil::CIRCLE)
	Erode the Footprint with a defined kernel.
void	erode (geom::SpanSet const &other)
	Erode the Footprint with a defined kernel.
void	removeOrphanPeaks ()
	Remove peaks from the PeakCatalog that fall outside the area of the Footprint.
void	updatePeakSignificance (double sigma)
	Compute and update the significance of each peak, given a single value for sigma.
void	updatePeakSignificance (image::Image< float > const &variance, int polarity)
	Compute and update the significance of each peak, using the variance image.
bool	isContiguous () const
	Reports if the Footprint is simply connected or has multiple components.
std::vector< std::shared_ptr< Footprint > >	split () const
	Split a multi-component Footprint into a vector of contiguous Footprints.
bool	operator== (Footprint const &other) const
	equality operator
void	writeFits (std::string const &fileName, std::string const &mode="w") const
	Write the object to a regular FITS file.
void	writeFits (fits::MemFileManager &manager, std::string const &mode="w") const
	Write the object to a FITS image in memory.
void	writeFits (fits::Fits &fitsfile) const
	Write the object to an already-open FITS object.

Static Public Member Functions
static std::shared_ptr< lsst::afw::detection::Footprint >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object.
static std::shared_ptr< lsst::afw::detection::Footprint >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file.
static std::shared_ptr< lsst::afw::detection::Footprint >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory.
static std::shared_ptr< lsst::afw::detection::Footprint >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr.

Protected Types
using	OutputArchiveHandle = io::OutputArchiveHandle

Protected Member Functions
std::string	getPersistenceName () const override
	Return the name correspoinging ot the persistence type.
std::string	getPythonModule () const override
	Return the python module the object will live in.
void	write (OutputArchiveHandle &handle) const override
	Write an instance of a Footprint to an output Archive.

Static Protected Member Functions
static std::unique_ptr< Footprint >	readSpanSet (afw::table::BaseCatalog const &, afw::table::io::InputArchive const &)
	Static method used to unpersist the SpanSet member of the Footprint class.
static void	readPeaks (afw::table::BaseCatalog const &, Footprint &)
	Static method used to unpersist the PeakCatalog member of the Footprint class.

Friends
class	FootprintFactory
class	FootprintMerge

Detailed Description

Class to describe the properties of a detected object from an image.

A Footprint is designed to be constructed with information about a detected object in an image. Internally a Footprint holds a SpanSet which is used to describe the location of the object in the image (the x, y pixel locations which are considered part of the object). In addition a Footprint contains a PeakCatalog which is used to store the location and intensity of peaks in the detection.

Definition at line 62 of file Footprint.h.

Member Typedef Documentation

OutputArchiveHandle

using lsst::afw::table::io::Persistable::OutputArchiveHandle = io::OutputArchiveHandle

protectedinherited

Definition at line 108 of file Persistable.h.

Constructor & Destructor Documentation

Footprint() [1/5]

Footprint::Footprint ( std::shared_ptr< geom::SpanSet > inputSpans, lsst::geom::Box2I const & region = lsst::geom::Box2I() )

explicit

Constructor for Footprint object.

Parameters

inputSpans	Shared pointer to a SpanSet defining the pixels included in the Footprint.
region	Bounding box of the image in which the Footprint was created, defaults to empty box.

Definition at line 38 of file Footprint.cc.

        : _spans(inputSpans), _peaks(PeakTable::makeMinimalSchema()), _region(region) {}

Footprint() [2/5]

Footprint::Footprint ( std::shared_ptr< geom::SpanSet > inputSpans, afw::table::Schema const & peakSchema, lsst::geom::Box2I const & region = lsst::geom::Box2I() )

explicit

Constructor for the Footprint object.

Parameters

inputSpans	Shared pointer to a SpanSet defining the pixels included in the Footprint.
peakSchema	schema to be used in the PeakCatalog
region	Bounding box of the image in which the Footprint was created, defaults to empty box.

Definition at line 41 of file Footprint.cc.

        : _spans(inputSpans), _peaks(peakSchema), _region(region) {}

Footprint() [3/5]

lsst::afw::detection::Footprint::Footprint ( )

inlineexplicit

Constructor of a empty Footprint object.

Definition at line 96 of file Footprint.h.

            : _spans(std::make_shared<geom::SpanSet>()),
              _peaks(PeakTable::makeMinimalSchema()),
              _region(lsst::geom::Box2I()) {}

Footprint() [4/5]

lsst::afw::detection::Footprint::Footprint ( Footprint const & other )

default

Footprint() [5/5]

lsst::afw::detection::Footprint::Footprint ( Footprint && )

default

~Footprint()

lsst::afw::detection::Footprint::~Footprint ( )

overridedefault

Member Function Documentation

addPeak()

std::shared_ptr< PeakRecord > Footprint::addPeak	(	float	fx,
		float	fy,
		float	value )

Convenience function to add a peak.

Parameters

fx	Float containing the x position of a peak
fy	Float containing the y position of a peak
value	The intensity value of the peak

Definition at line 47 of file Footprint.cc.

                                                                             {
    std::shared_ptr<PeakRecord> p = getPeaks().addNew();
    p->setIx(fx);
    p->setIy(fy);
    p->setFx(fx);
    p->setFy(fy);
    p->setPeakValue(height);
    return p;
}

clipTo()

void Footprint::clipTo

(

lsst::geom::Box2I const &

bbox

)

Clip the Footprint such that all values lie inside the supplied Bounding Box.

Parameters

bbox	Integer box object that defines the boundaries the footprint should be clipped to.

Definition at line 74 of file Footprint.cc.

                                               {
    setSpans(getSpans()->clippedTo(box));
    removeOrphanPeaks();
}

contains()

bool Footprint::contains

(

lsst::geom::Point2I const &

pix

)

const

Tests if a pixel postion falls inside the Footprint.

Parameters

pix	Integer point object defining the position of a pixel to test

Definition at line 79 of file Footprint.cc.

{ return getSpans()->contains(pix); }

dilate() [1/2]

void Footprint::dilate

(

geom::SpanSet const &

other

)

Dilate the Footprint with a defined kernel.

This function enlarges the SpanSet which defines the area of the Footprint by an amount governed by the input kernel

Parameters

other

SpanSet to use as the kernel in dilation

Definition at line 124 of file Footprint.cc.

{ setSpans(getSpans()->dilated(other)); }

dilate() [2/2]

void Footprint::dilate	(	int	r,
		geom::Stencil	s = geom::Stencil::CIRCLE )

Dilate the Footprint with a defined kernel.

This function enlarges the SpanSet which defines the area of the Footprint by an amount governed by in input kernel

Parameters

r	The radius of the stencil object used to create a dilation kernel
s	The stencil object used to create the dilation kernel

Definition at line 122 of file Footprint.cc.

{ setSpans(getSpans()->dilated(r, s)); }

dynamicCast()

template std::shared_ptr< meas::extensions::psfex::PsfexPsf > lsst::afw::table::io::PersistableFacade< lsst::afw::detection::Footprint >::dynamicCast ( std::shared_ptr< Persistable > const & ptr )

staticinherited

Dynamically cast a shared_ptr.

Dynamically cast a shared pointer and raise on failure.

You must provide an explicit template instantiation in the .cc file for each class that inherits from PersistableFacade. Designed to work around RTTI issues on macOS with hidden symbols;

Exceptions

lsst::pex::exceptions::LogicError

if the cast fails

param[in] ptr The pointer to be cast.

Returns

The cast pointer.

Exceptions

lsst::pex::exceptions::TypeError

If the dynamic cast fails.

Definition at line 218 of file Persistable.cc.

erode() [1/2]

void Footprint::erode

(

geom::SpanSet const &

other

)

Erode the Footprint with a defined kernel.

This function reduces the size of the SpanSet which defines the area of the Footprint by an amount governed by the input kernel

Parameters

other

SpanSet to use as the kernel in erosion

Definition at line 131 of file Footprint.cc.

                                              {
    setSpans(getSpans()->eroded(other));
    removeOrphanPeaks();
}

erode() [2/2]

void Footprint::erode	(	int	r,
		geom::Stencil	s = geom::Stencil::CIRCLE )

Erode the Footprint with a defined kernel.

This function reduces the size of the SpanSet which defines the area of the Footprint by an amount governed by the input kernel

Parameters

r	The radius of the stencil object used to create a erosion kernel
s	The stencil object used to create the erosion kernel

Definition at line 126 of file Footprint.cc.

                                          {
    setSpans(getSpans()->eroded(r, s));
    removeOrphanPeaks();
}

getArea()

std::size_t lsst::afw::detection::Footprint::getArea ( ) const

inline

Return the number of pixels in this Footprint.

This function returns the real number of pixels, not the area of the bbox.

Definition at line 173 of file Footprint.h.

{ return _spans->getArea(); }

getBBox()

lsst::geom::Box2I lsst::afw::detection::Footprint::getBBox ( ) const

inline

Return the Footprint's bounding box.

Definition at line 208 of file Footprint.h.

{ return _spans->getBBox(); }

getCentroid()

lsst::geom::Point2D lsst::afw::detection::Footprint::getCentroid ( ) const

inline

Return the Footprint's centroid.

The centroid is calculated as the mean of the pixel centers

Definition at line 180 of file Footprint.h.

{ return _spans->computeCentroid(); }

getPeaks() [1/2]

PeakCatalog & lsst::afw::detection::Footprint::getPeaks ( )

inline

Return the Peaks contained in this Footprint.

The peaks should be ordered by decreasing pixel intensity at the peak position (so the most negative peak appears last). Users that add new Peaks manually are responsible for maintaining this sorting.

Definition at line 129 of file Footprint.h.

{ return _peaks; }

getPeaks() [2/2]

const PeakCatalog & lsst::afw::detection::Footprint::getPeaks ( ) const

inline

Definition at line 130 of file Footprint.h.

{ return _peaks; }

getPersistenceName()

std::string Footprint::getPersistenceName ( ) const

overrideprotectedvirtual

Return the name correspoinging ot the persistence type.

Reimplemented from lsst::afw::table::io::Persistable.

Reimplemented in lsst::afw::detection::HeavyFootprint< ImagePixelT, MaskPixelT, VariancePixelT >.

Definition at line 269 of file Footprint.cc.

{ return getFootprintPersistenceName(); }

getPythonModule()

std::string lsst::afw::detection::Footprint::getPythonModule ( ) const

inlineoverrideprotectedvirtual

Return the python module the object will live in.

Reimplemented from lsst::afw::table::io::Persistable.

Definition at line 385 of file Footprint.h.

{ return "lsst.afw.detection"; }

getRegion()

lsst::geom::Box2I lsst::afw::detection::Footprint::getRegion ( ) const

inline

Return the corners of the MaskedImage the footprints live in.

Definition at line 213 of file Footprint.h.

{ return _region; }

getShape()

geom::ellipses::Quadrupole lsst::afw::detection::Footprint::getShape ( ) const

inline

Return the Footprint's shape (interpreted as an ellipse)

The shape is determined by measuring the moments of the pixel centers about its centroid (cf. getCentroid)

Definition at line 188 of file Footprint.h.

{ return _spans->computeShape(); }

getSpans()

std::shared_ptr< geom::SpanSet > lsst::afw::detection::Footprint::getSpans ( ) const

inline

Return a shared pointer to the SpanSet.

Definition at line 115 of file Footprint.h.

{ return _spans; }

isContiguous()

bool lsst::afw::detection::Footprint::isContiguous ( ) const

inline

Reports if the Footprint is simply connected or has multiple components.

Definition at line 358 of file Footprint.h.

{ return getSpans()->isContiguous(); };

isHeavy()

virtual bool lsst::afw::detection::Footprint::isHeavy ( ) const

inlinevirtual

Indicates if this object is a HeavyFootprint.

Reimplemented in lsst::afw::detection::HeavyFootprint< ImagePixelT, MaskPixelT, VariancePixelT >.

Definition at line 111 of file Footprint.h.

{ return false; }

isPersistable()

bool lsst::afw::detection::Footprint::isPersistable ( ) const

inlineoverridevirtualnoexcept

Report if this object is persistable.

Reimplemented from lsst::afw::table::io::Persistable.

Definition at line 283 of file Footprint.h.

{ return true; }

operator=() [1/2]

Footprint & lsst::afw::detection::Footprint::operator= ( Footprint && )

default

operator=() [2/2]

Footprint & lsst::afw::detection::Footprint::operator= ( Footprint const & other )

default

operator==()

bool Footprint::operator==

(

Footprint const &

other

)

const

equality operator

Parameters

other

The Footprint for which equality will be computed

Definition at line 176 of file Footprint.cc.

                                                       {
    /* If the peakCatalogs are not the same length the Footprints can't be equal */
    if (getPeaks().size() != other.getPeaks().size()) {
        return false;
    }
    /* Check that for every peak in the PeakCatalog there is a corresponding peak
     * in the other, and if not return false
     */
    for (auto const& selfPeak : getPeaks()) {
        bool match = false;
        for (auto const& otherPeak : other.getPeaks()) {
            if (selfPeak.getI() == otherPeak.getI() && selfPeak.getF() == otherPeak.getF() &&
                selfPeak.getPeakValue() == otherPeak.getPeakValue()) {
                match = true;
                break;
            }
        }
        if (!match) {
            return false;
        }
    }
    /* At this point the PeakCatalogs have evaluated true, compare the SpanSets
     */
    return *(getSpans()) == *(other.getSpans());
}

readFits() [1/3]

static std::shared_ptr< lsst::afw::detection::Footprint > lsst::afw::table::io::PersistableFacade< lsst::afw::detection::Footprint >::readFits ( fits::Fits & fitsfile )

inlinestaticinherited

Read an object from an already open FITS object.

Parameters

[in]

fitsfile

FITS object to read from, already positioned at the desired HDU.

Definition at line 183 of file Persistable.h.

readFits() [2/3]

static std::shared_ptr< lsst::afw::detection::Footprint > lsst::afw::table::io::PersistableFacade< lsst::afw::detection::Footprint >::readFits ( fits::MemFileManager & manager, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a FITS file in memory.

Parameters

[in]	manager	Manager for the memory to read from.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 205 of file Persistable.h.

readFits() [3/3]

static std::shared_ptr< lsst::afw::detection::Footprint > lsst::afw::table::io::PersistableFacade< lsst::afw::detection::Footprint >::readFits ( std::string const & fileName, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a regular FITS file.

Parameters

[in]	fileName	Name of the file to read.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 194 of file Persistable.h.

readPeaks()

void Footprint::readPeaks ( afw::table::BaseCatalog const & peakCat, Footprint & loadedFootprint )

staticprotected

Static method used to unpersist the PeakCatalog member of the Footprint class.

Definition at line 310 of file Footprint.cc.

                                                                                        {
    using namespace std::string_literals;
    if (!peakCat.getSchema().contains(PeakTable::makeMinimalSchema())) {
        // need to handle an older form of Peak persistence for backwards compatibility
        afw::table::SchemaMapper mapper(peakCat.getSchema());
        mapper.addMinimalSchema(PeakTable::makeMinimalSchema());
        afw::table::Key<float> oldX = peakCat.getSchema()["x"];
        afw::table::Key<float> oldY = peakCat.getSchema()["y"];
        afw::table::Key<float> oldPeakValue = peakCat.getSchema()["value"];
        mapper.addMapping(oldX, "f.x"s);
        mapper.addMapping(oldY, "f.y"s);
        mapper.addMapping(oldPeakValue, "peakValue"s);
        loadedFootprint.setPeakSchema(mapper.getOutputSchema());
        auto peaks = loadedFootprint.getPeaks();
        peaks.reserve(peakCat.size());
        for (auto const& peak : peakCat) {
            auto newPeak = peaks.addNew();
            newPeak->assign(peak, mapper);
            newPeak->setIx(static_cast<int>(newPeak->getFx()));
            newPeak->setIy(static_cast<int>(newPeak->getFy()));
        }
        return;
    }
    loadedFootprint.setPeakSchema(peakCat.getSchema());
    auto& peaks = loadedFootprint.getPeaks();
    peaks.reserve(peakCat.size());
    for (auto const& peak : peakCat) {
        peaks.addNew()->assign(peak);
    }
}

readSpanSet()

std::unique_ptr< Footprint > Footprint::readSpanSet ( afw::table::BaseCatalog const & catalog, afw::table::io::InputArchive const & archive )

staticprotected

Static method used to unpersist the SpanSet member of the Footprint class.

Definition at line 286 of file Footprint.cc.

                                                                                         {
    int fieldCount = catalog.getSchema().getFieldCount();
    LSST_ARCHIVE_ASSERT(fieldCount == 1 || fieldCount == 3);
    std::shared_ptr<geom::SpanSet> loadedSpanSet;
    if (fieldCount == 1) {
        // This is a new style footprint with a SpanSet as a member, treat accordingly
        auto const schemaAndKey = spanSetPersistenceHelper();
        int persistedSpanSetId = catalog.front().get(schemaAndKey.second);
        loadedSpanSet = std::dynamic_pointer_cast<geom::SpanSet>(archive.get(persistedSpanSetId));
    } else {
        // This block is for an old style footprint load.
        auto const& keys = LegacyFootprintPersistenceHelper::get();
        std::vector<geom::Span> tempVec;
        tempVec.reserve(catalog.size());
        for (auto const& val : catalog) {
            tempVec.emplace_back(val.get(keys.spanY), val.get(keys.spanX0), val.get(keys.spanX1));
        }
        loadedSpanSet = std::make_shared<geom::SpanSet>(std::move(tempVec));
    }
    auto loadedFootprint = std::unique_ptr<Footprint>(new Footprint(loadedSpanSet));
    return loadedFootprint;
}

removeOrphanPeaks()

void Footprint::removeOrphanPeaks

(

)

Remove peaks from the PeakCatalog that fall outside the area of the Footprint.

Definition at line 136 of file Footprint.cc.

                                  {
    for (auto iter = getPeaks().begin(); iter != getPeaks().end(); ++iter) {
        if (!getSpans()->contains(lsst::geom::Point2I(iter->getIx(), iter->getIy()))) {
            iter = getPeaks().erase(iter);
            --iter;
        }
    }
}

setPeakCatalog()

void Footprint::setPeakCatalog

(

PeakCatalog const &

otherPeaks

)

Set the peakCatalog to a copy of the supplied catalog.

PeakCatalog will be copied into the Footprint, but a PeakCatalog is a shallow copy, so records will not be duplicated. This function will throw an error if the PeakCatalog of *this is not empty.

Parameters

otherPeaks

The PeakCatalog to copy

Definition at line 435 of file Footprint.cc.

                                                            {
    if (!getPeaks().empty()) {
        throw LSST_EXCEPT(pex::exceptions::LogicError, "Cannot change the PeakCatalog unless it is empty");
    }
    // this syntax doesn't work in Python, which is why this method has to exist
    getPeaks() = otherPeaks;
}

setPeakSchema()

void Footprint::setPeakSchema

(

afw::table::Schema const &

peakSchema

)

Set the Schema used by the PeakCatalog (will throw if PeakCatalog is not empty).

Parameters

peakSchema

The schema to use in the PeakCatalog

Exceptions

pex::exceptions::LogicError

Thrown if if the PeakCatalog is not empty

Definition at line 431 of file Footprint.cc.

                                                              {
    setPeakCatalog(PeakCatalog(peakSchema));
}

setRegion()

void lsst::afw::detection::Footprint::setRegion ( lsst::geom::Box2I const & region )

inline

Set the corners of the MaskedImage wherein the footprints dwell.

Parameters

region

A box describing the corners of the Image the Footprint derives from

Definition at line 220 of file Footprint.h.

{ _region = region; }

setSpans()

void Footprint::setSpans

(

std::shared_ptr< geom::SpanSet >

otherSpanSet

)

Sets the shared pointer to the SpanSet in the Footprint.

Parameters

otherSpanSet

Shared pointer to a SpanSet

Definition at line 45 of file Footprint.cc.

{ _spans = otherSpanSet; }

shift() [1/2]

void Footprint::shift	(	int	dx,
		int	dy )

Shift a Footprint by (dx, dy)

Parameters

dx	How much to move Footprint in column direction
dy	How much to move in row direction

Definition at line 64 of file Footprint.cc.

                                    {
    setSpans(getSpans()->shiftedBy(dx, dy));
    for (auto& peak : getPeaks()) {
        peak.setIx(peak.getIx() + dx);
        peak.setIy(peak.getIy() + dy);
        peak.setFx(peak.getFx() + dx);
        peak.setFy(peak.getFy() + dy);
    }
}

shift() [2/2]

void lsst::afw::detection::Footprint::shift ( lsst::geom::ExtentI const & d )

inline

Shift a Footprint by a given extent.

Parameters

d	ExtentI object which gives the dimensions the Footprint should be shifted

Definition at line 203 of file Footprint.h.

{ shift(d.getX(), d.getY()); }

sortPeaks()

void Footprint::sortPeaks

(

afw::table::Key< float > const &

key = afw::table::Key<float>()

)

Sort Peaks from most positive value to most negative.

If the key passed is invalid (the default) PeakTable::getPeakValueKey() will be used.

Parameters

key	A key corresponding to the field in the Schema the PeakCatalog is to be sorted by.

Definition at line 57 of file Footprint.cc.

                                                       {
    auto validatedKey = key.isValid() ? key : PeakTable::getPeakValueKey();
    getPeaks().sort([&validatedKey](detection::PeakRecord const& a, detection::PeakRecord const& b) {
        return a.get(validatedKey) > b.get(validatedKey);
    });
}

split()

std::vector< std::shared_ptr< Footprint > > Footprint::split

(

)

const

Split a multi-component Footprint into a vector of contiguous Footprints.

Split a multi-component Footprint such that each Footprint in the output vector is contiguous and contains only peaks that can be found within the bounds of the Footprint

Definition at line 159 of file Footprint.cc.

                                                           {
    auto splitSpanSets = getSpans()->split();
    std::vector<std::shared_ptr<Footprint>> footprintList;
    footprintList.reserve(splitSpanSets.size());
    for (auto& spanPtr : splitSpanSets) {
        auto tmpFootprintPointer = std::make_shared<Footprint>(spanPtr, getPeaks().getSchema(), getRegion());
        tmpFootprintPointer->_peaks = getPeaks();
        // No need to remove any peaks, as there is only one Footprint, so it will
        // simply be a copy of the original
        if (splitSpanSets.size() > 1) {
            tmpFootprintPointer->removeOrphanPeaks();
        }
        footprintList.push_back(std::move(tmpFootprintPointer));
    }
    return footprintList;
}

transform() [1/4]

std::shared_ptr< Footprint > Footprint::transform	(	geom::TransformPoint2ToPoint2 const &	t,
		lsst::geom::Box2I const &	region,
		bool	doClip = true ) const

Return a new Footprint whose pixels are the product of applying the specified transformation.

Parameters

t	A 2-D transform which will be used to map the pixels
region	Used to set the "region" box of the returned footprint; note that this is NOT the same as the footprint's bounding box.
doClip	If true, clip the new footprint to the region bbox before returning it.

Definition at line 98 of file Footprint.cc.

                                                                                                {
    // Transfrom the SpanSet first
    auto transformedSpan = getSpans()->transformedBy(t);
    // Use this new SpanSet and the peakSchema to create a new Footprint
    auto newFootprint = std::make_shared<Footprint>(transformedSpan, getPeaks().getSchema(), region);
    // now populate the new Footprint with transformed Peaks
    std::vector<lsst::geom::Point2D> peakPosList;
    peakPosList.reserve(_peaks.size());
    for (auto const& peak : getPeaks()) {
        peakPosList.emplace_back(peak.getF());
    }
    auto newPeakPosList = t.applyForward(peakPosList);
    auto newPeakPos = newPeakPosList.cbegin();
    for (auto peak = getPeaks().cbegin(), endPeak = getPeaks().cend(); peak != endPeak;
         ++peak, ++newPeakPos) {
        newFootprint->addPeak(newPeakPos->getX(), newPeakPos->getY(), peak->getPeakValue());
    }
    if (doClip) {
        newFootprint->clipTo(region);
    }
    return newFootprint;
}

transform() [2/4]

std::shared_ptr< Footprint > Footprint::transform	(	lsst::geom::AffineTransform const &	t,
		lsst::geom::Box2I const &	region,
		bool	doClip = true ) const

Return a new Footprint whose pixels are the product of applying the specified transformation.

Parameters

t	An affine transform object which will be used to map the pixels
region	Used to set the "region" box of the returned footprint; note that this is NOT the same as the footprint's bounding box.
doClip	If true, clip the new footprint to the region bbox before returning it.

Definition at line 93 of file Footprint.cc.

                                                                                                {
    return transform(*geom::makeTransform(t), region, doClip);
}

transform() [3/4]

std::shared_ptr< Footprint > Footprint::transform	(	lsst::geom::LinearTransform const &	t,
		lsst::geom::Box2I const &	region,
		bool	doClip = true ) const

Return a new Footprint whose pixels are the product of applying the specified transformation.

Parameters

t	A linear transform object which will be used to map the pixels
region	Used to set the "region" box of the returned footprint; note that this is NOT the same as the footprint's bounding box.
doClip	If true, clip the new footprint to the region bbox before returning it.

Definition at line 88 of file Footprint.cc.

                                                                                                {
    return transform(lsst::geom::AffineTransform(t), region, doClip);
}

transform() [4/4]

std::shared_ptr< Footprint > Footprint::transform	(	std::shared_ptr< geom::SkyWcs >	source,
		std::shared_ptr< geom::SkyWcs >	target,
		lsst::geom::Box2I const &	region,
		bool	doClip = true ) const

Transform the footprint from one WCS to another.

Parameters

source	Wcs that defines the coordinate system of the input footprint.
target	Wcs that defines that desired coordinate system of the returned footprint.
region	Used to set the "region" box of the returned footprint; note that this is NOT the same as the footprint's bounding box.
doClip	If true, clip the new footprint to the region bbox before returning it.

Definition at line 81 of file Footprint.cc.

                                                                                                {
    auto srcToTarget = geom::makeWcsPairTransform(*source, *target);
    return transform(*srcToTarget, region, doClip);
}

updatePeakSignificance() [1/2]

void Footprint::updatePeakSignificance

(

double

sigma

)

Compute and update the significance of each peak, given a single value for sigma.

The Footprint peak schema must already have a significance field in it.

Parameters

sigma

The standard deviation for peak detection, positive or negative as appropriate.

Exceptions

pex::exceptions::NotFoundError

Thrown if the the peaks do not have a significance field.

Definition at line 145 of file Footprint.cc.

                                                   {
    auto key = _peaks.getSchema().find<double>("significance").key;
    for (auto& peak : _peaks) {
        peak.set(key, peak.getPeakValue() / sigma);
    }
}

updatePeakSignificance() [2/2]

void Footprint::updatePeakSignificance	(	image::Image< float > const &	variance,
		int	polarity )

Compute and update the significance of each peak, using the variance image.

The Footprint peak schema must already have a significance field in it.

Parameters

variance	The variance plane of the image that this footprint is in.
polarity	+1 if this is detected as a positive footprint, -1 if negative.

Exceptions

pex::exceptions::NotFoundError

Thrown if the the peaks do not have a significance field.

Definition at line 152 of file Footprint.cc.

                                                                                      {
    auto key = _peaks.getSchema().find<double>("significance").key;
    for (auto& peak : _peaks) {
        peak.set(key, polarity * peak.getPeakValue() / std::sqrt(variance[peak.getI()]));
    }
}

write()

void Footprint::write ( OutputArchiveHandle & handle ) const

overrideprotectedvirtual

Write an instance of a Footprint to an output Archive.

Reimplemented from lsst::afw::table::io::Persistable.

Reimplemented in lsst::afw::detection::HeavyFootprint< ImagePixelT, MaskPixelT, VariancePixelT >.

Definition at line 271 of file Footprint.cc.

                                                                 {
    // get the span schema and key
    auto const keys = spanSetPersistenceHelper();
    // create the output catalog
    afw::table::BaseCatalog spanSetCat = handle.makeCatalog(keys.first);
    // create a record that will hold the ID of the recursively saved SpanSet
    auto record = spanSetCat.addNew();
    record->set(keys.second, handle.put(getSpans()));
    handle.saveCatalog(spanSetCat);
    // save the peaks into a catalog
    afw::table::BaseCatalog peakCat = handle.makeCatalog(getPeaks().getSchema());
    peakCat.insert(peakCat.end(), getPeaks().begin(), getPeaks().end(), true);
    handle.saveCatalog(peakCat);
}

writeFits() [1/3]

void lsst::afw::table::io::Persistable::writeFits ( fits::Fits & fitsfile ) const

inherited

Write the object to an already-open FITS object.

Parameters

[in]

fitsfile

Open FITS object to write to.

Definition at line 18 of file Persistable.cc.

                                                    {
    OutputArchive archive;
    archive.put(this);
    archive.writeFits(fitsfile);
}

writeFits() [2/3]

void lsst::afw::table::io::Persistable::writeFits ( fits::MemFileManager & manager, std::string const & mode = "w" ) const

inherited

Write the object to a FITS image in memory.

Parameters

[in]	manager	Name of the file to write to.
[in]	mode	If "w", any existing file with the given name will be overwritten. If "a", new HDUs will be appended to an existing file.

Definition at line 29 of file Persistable.cc.

                                                                                    {
    fits::Fits fitsfile(manager, mode, fits::Fits::AUTO_CLOSE | fits::Fits::AUTO_CHECK);
    writeFits(fitsfile);
}

writeFits() [3/3]

void lsst::afw::table::io::Persistable::writeFits ( std::string const & fileName, std::string const & mode = "w" ) const

inherited

Write the object to a regular FITS file.

Parameters

[in]	fileName	Name of the file to write to.
[in]	mode	If "w", any existing file with the given name will be overwritten. If "a", new HDUs will be appended to an existing file.

Definition at line 24 of file Persistable.cc.

                                                                                  {
    fits::Fits fitsfile(fileName, mode, fits::Fits::AUTO_CLOSE | fits::Fits::AUTO_CHECK);
    writeFits(fitsfile);
}

Friends And Related Symbol Documentation

FootprintFactory

friend class FootprintFactory

friend

Definition at line 392 of file Footprint.h.

FootprintMerge

friend class FootprintMerge

friend

Definition at line 405 of file Footprint.h.

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/afw/g9726552aa6+10f999ec6a/include/lsst/afw/detection/Footprint.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/afw/g9726552aa6+10f999ec6a/src/detection/Footprint.cc