lsst::afw::detection::Psf Class Reference

A polymorphic base class for representing an image's Point Spread Function. More...

#include <Psf.h>

Inheritance diagram for lsst::afw::detection::Psf:

Public Types
enum	ImageOwnerEnum { COPY = 0 , INTERNAL = 1 }
	Enum passed to computeImage and computeKernelImage to determine image ownership. More...
using	Pixel = math::Kernel::Pixel
	Pixel type of Image returned by computeImage. More...
using	Image = image::Image< Pixel >
	Image type returned by computeImage. More...

Public Member Functions
	Psf (Psf const &)
Psf &	operator= (Psf const &)=delete
Psf &	operator= (Psf &&)=delete
	Psf (Psf &&)
	~Psf () override
virtual std::shared_ptr< Psf >	clone () const =0
	Polymorphic deep-copy. More...
std::shared_ptr< typehandling::Storable >	cloneStorable () const override
	Polymorphic deep-copy. More...
virtual std::shared_ptr< Psf >	resized (int width, int height) const =0
	Return clone with specified kernel dimensions. More...
std::shared_ptr< Image >	computeImage (lsst::geom::Point2D position, image::Color color=image::Color(), ImageOwnerEnum owner=COPY) const
	Return an Image of the PSF, in a form that can be compared directly with star images. More...
std::shared_ptr< Image >	computeImage () const
std::shared_ptr< Image >	computeKernelImage (lsst::geom::Point2D position, image::Color color=image::Color(), ImageOwnerEnum owner=COPY) const
	Return an Image of the PSF, in a form suitable for convolution. More...
std::shared_ptr< Image >	computeKernelImage () const
double	computePeak (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Return the peak value of the PSF image. More...
double	computePeak () const
double	computeApertureFlux (double radius, lsst::geom::Point2D position, image::Color color=image::Color()) const
	Compute the "flux" of the Psf model within a circular aperture of the given radius. More...
double	computeApertureFlux (double radius) const
geom::ellipses::Quadrupole	computeShape (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Compute the ellipse corresponding to the second moments of the Psf. More...
geom::ellipses::Quadrupole	computeShape () const
std::shared_ptr< math::Kernel const >	getLocalKernel (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Return a FixedKernel corresponding to the Psf image at the given point. More...
std::shared_ptr< math::Kernel const >	getLocalKernel () const
image::Color	getAverageColor () const
	Return the average Color of the stars used to construct the Psf. More...
virtual lsst::geom::Point2D	getAveragePosition () const
	Return the average position of the stars used to construct the Psf. More...
lsst::geom::Box2I	computeBBox (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Return the bounding box of the image returned by computeKernelImage() More...
lsst::geom::Box2I	computeBBox () const
lsst::geom::Box2I	computeImageBBox (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Return the bounding box of the image returned by computeImage() More...
lsst::geom::Box2I	computeImageBBox () const
lsst::geom::Box2I	computeKernelBBox (lsst::geom::Point2D position, image::Color color=image::Color()) const
	Return the bounding box of the image returned by computeImage() More...
lsst::geom::Box2I	computeKernelBBox () const
std::size_t	getCacheCapacity () const
	Return the capacity of the caches. More...
void	setCacheCapacity (std::size_t capacity)
	Set the capacity of the caches. More...
virtual std::string	toString () const
	Create a string representation of this object (optional operation). More...
virtual std::size_t	hash_value () const
	Return a hash of this object (optional operation). More...
virtual bool	equals (Storable const &other) const noexcept
	Compare this object to another Storable. More...
void	writeFits (std::string const &fileName, std::string const &mode="w") const
	Write the object to a regular FITS file. More...
void	writeFits (fits::MemFileManager &manager, std::string const &mode="w") const
	Write the object to a FITS image in memory. More...
void	writeFits (fits::Fits &fitsfile) const
	Write the object to an already-open FITS object. More...
virtual bool	isPersistable () const noexcept
	Return true if this particular object can be persisted using afw::table::io. More...

Static Public Member Functions
static std::shared_ptr< Image >	recenterKernelImage (std::shared_ptr< Image > im, lsst::geom::Point2D const &position, std::string const &warpAlgorithm="lanczos5", unsigned int warpBuffer=5)
	Helper function for Psf::doComputeImage(): converts a kernel image (centered at (0,0) when xy0 is taken into account) to an image centered at position when xy0 is taken into account. More...
static std::shared_ptr< Psf >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object. More...
static std::shared_ptr< Psf >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file. More...
static std::shared_ptr< Psf >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory. More...
static std::shared_ptr< Psf >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr. More...

Protected Types
using	OutputArchiveHandle = io::OutputArchiveHandle

Protected Member Functions
	Psf (bool isFixed=false, std::size_t capacity=100)
	Main constructor for subclasses. More...
virtual std::shared_ptr< Image >	doComputeImage (lsst::geom::Point2D const &position, image::Color const &color) const
	These virtual members are protected (rather than private) so that python-implemented derived classes may opt to use the default implementations. More...
virtual lsst::geom::Box2I	doComputeImageBBox (lsst::geom::Point2D const &position, image::Color const &color) const
virtual std::string	getPersistenceName () const
	Return the unique name used to persist this object and look up its factory. More...
virtual std::string	getPythonModule () const
	Return the fully-qualified Python module that should be imported to guarantee that its factory is registered. More...
virtual void	write (OutputArchiveHandle &handle) const
	Write the object to one or more catalogs. More...

Static Protected Member Functions
template<class T >
static bool	singleClassEquals (T const &lhs, Storable const &rhs)
	Test if a Storable is of a particular class and equal to another object. More...

Private Member Functions
virtual std::shared_ptr< Image >	doComputeKernelImage (lsst::geom::Point2D const &position, image::Color const &color) const =0
	These virtual member functions are private, not protected, because we only want derived classes to implement them, not call them; they should call the corresponding compute*Image member functions instead so as to let the Psf base class handle caching properly. More...
virtual double	doComputeApertureFlux (double radius, lsst::geom::Point2D const &position, image::Color const &color) const =0
virtual geom::ellipses::Quadrupole	doComputeShape (lsst::geom::Point2D const &position, image::Color const &color) const =0
virtual lsst::geom::Box2I	doComputeBBox (lsst::geom::Point2D const &position, image::Color const &color) const =0

Related Functions
(Note that these are not member functions.)
std::ostream &	operator<< (std::ostream &os, Storable const &storable)
	Output operator for Storable. More...

Detailed Description

A polymorphic base class for representing an image's Point Spread Function.

Most of a Psf's functionality involves its evaluation at a position and color, either or both of which may be unspecified (which will result in evaluation at some average position or color). Unlike the closely-related Kernel class, there is no requirement that a Psf have a well-defined spatial function or any parameters. Psfs are not necessarily continuous, and the dimensions of image of the Psf at a point may not be fixed.

Psfs have two methods for getting at image at a point:

• the image returned by computeImage() is in the same coordinate system as the pixelized image
• the image returned by computeKernelImage() is in an offset coordinate system with the point P at (0,0); this implies that the image (x0,y0) will be negative

Because P does not need to have integer coordinates, these two images are fractionally offset from each other and we use interpolation to get (1) from (2).

Psfs are immutable - derived classes should have no non-const methods, and hence should be fully-defined after construction. This allows shared_ptrs to Psfs to be passed around and shared between objects without concern for whether they will be unexpectedly modified.

In most cases, Psf derived classes should inherit from meas::algorithms::ImagePsf or meas::algorithms::KernelPsf, as these will provide default implementions for several member functions.

Definition at line 75 of file Psf.h.

Member Typedef Documentation

Image

using lsst::afw::detection::Psf::Image = image::Image<Pixel>

Image type returned by computeImage.

Definition at line 83 of file Psf.h.

OutputArchiveHandle

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

protectedinherited

Definition at line 108 of file Persistable.h.

Pixel

using lsst::afw::detection::Psf::Pixel = math::Kernel::Pixel

Pixel type of Image returned by computeImage.

Definition at line 82 of file Psf.h.

Member Enumeration Documentation

ImageOwnerEnum

enum lsst::afw::detection::Psf::ImageOwnerEnum

Enum passed to computeImage and computeKernelImage to determine image ownership.

Enumerator
COPY	The image will be copied before returning; caller will own it.
INTERNAL	An internal image will be returned without copying. The caller must not modify it, and it may be invalidated the next time a Psf member function is called with different color and/or position.

Definition at line 86 of file Psf.h.

                        {
        COPY = 0,    
        INTERNAL = 1 
    };

Constructor & Destructor Documentation

Psf() [1/3]

Psf::Psf

(

Psf const &

other

)

Definition at line 78 of file Psf.cc.

: Psf(other._isFixed, other.getCacheCapacity()) {}

Psf() [2/3]

Psf::Psf

(

Psf &&

other

)

Definition at line 80 of file Psf.cc.

        : _isFixed(other._isFixed),
          _imageCache(std::move(other._imageCache)),
          _kernelImageCache(std::move(other._kernelImageCache)) {}

~Psf()

Psf::~Psf ( )

overridedefault

Definition at line 125 of file psfImpl.cc.

          {
#if 0                                   // we don't own impl
    psf_end(impl);
#endif
}

Psf() [3/3]

Psf::Psf ( bool  isFixed = false, std::size_t  capacity = 100  )

explicitprotected

Main constructor for subclasses.

Parameters

[in]	isFixed	Should be true for Psf for which doComputeKernelImage always returns the same image, regardless of color or position arguments.
[in]	capacity	Capacity of the caches.

Definition at line 71 of file Psf.cc.

                                         : _isFixed(isFixed) {
    _imageCache = std::make_unique<PsfCache>(capacity);
    _kernelImageCache = std::make_unique<PsfCache>(capacity);
}

Member Function Documentation

clone()

virtual std::shared_ptr<Psf> lsst::afw::detection::Psf::clone ( ) const

pure virtual

Polymorphic deep-copy.

Because Psfs are immutable, clones should generally be unnecessary, but they may be useful in allowing Psfs to maintain separate caches for their most recently returned images.

Implemented in lsst::meas::extensions::psfex::PsfexPsf, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::SingleGaussianPsf, lsst::meas::algorithms::PcaPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::DoubleGaussianPsf, lsst::meas::algorithms::CoaddPsf, and lsst::afw::detection::GaussianPsf.

cloneStorable()

std::shared_ptr<typehandling::Storable> lsst::afw::detection::Psf::cloneStorable ( ) const

inlineoverridevirtual

Polymorphic deep-copy.

This method is an alias of clone that can be called from a reference to Storable.

Reimplemented from lsst::afw::typehandling::Storable.

Definition at line 116 of file Psf.h.

{ return clone(); }

computeApertureFlux() [1/2]

double Psf::computeApertureFlux

(

double

radius

)

const

Definition at line 179 of file Psf.cc.

                                                   {
    return computeApertureFlux(radius, makeNullPoint());
}

computeApertureFlux() [2/2]

double Psf::computeApertureFlux	(	double	radius,
		lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Compute the "flux" of the Psf model within a circular aperture of the given radius.

Parameters

[in]	radius	Radius of the aperture to measure.
[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

The flux is relative to a Psf image that has been normalized to unit integral, and the radius is in pixels.

Definition at line 183 of file Psf.cc.

                                                                                               {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    return doComputeApertureFlux(radius, position, color);
}

computeBBox() [1/2]

lsst::geom::Box2I Psf::computeBBox

(

)

const

Definition at line 135 of file Psf.cc.

                                     {
    return computeBBox(makeNullPoint());
}

computeBBox() [2/2]

lsst::geom::Box2I Psf::computeBBox	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Return the bounding box of the image returned by computeKernelImage()

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

Definition at line 139 of file Psf.cc.

                                                                               {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    return doComputeBBox(position, color);
}

computeImage() [1/2]

std::shared_ptr< Psf::Image > Psf::computeImage

(

)

const

Definition at line 101 of file Psf.cc.

                                                {
    return computeImage(makeNullPoint());
}

computeImage() [2/2]

std::shared_ptr< Psf::Image > Psf::computeImage	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color(),
		ImageOwnerEnum	owner = COPY
	)		const

Return an Image of the PSF, in a form that can be compared directly with star images.

The specified position is a floating point number, and the resulting image will have a Psf centered on that point when the returned image's xy0 is taken into account.

The returned image is normalized to sum to unity.

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().
[in]	owner	Whether to copy the return value or return an internal image that must be handled with care (see ImageOwnerEnum).

The Psf class caches the most recent return value of computeImage, so repeated calls with the same arguments will be highly optimized.

Note

The real work is done in the virtual private member function Psf::doComputeImage; computeImage only handles caching and default arguments.

Definition at line 105 of file Psf.cc.

                                                                          {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    std::shared_ptr<Psf::Image> result = (*_imageCache)(
            detail::PsfCacheKey(position, color),
            [this](detail::PsfCacheKey const &key) { return doComputeImage(key.position, key.color); });
    if (owner == COPY) {
        result = std::make_shared<Image>(*result, true);
    }
    return result;
}

computeImageBBox() [1/2]

lsst::geom::Box2I Psf::computeImageBBox

(

)

const

Definition at line 145 of file Psf.cc.

                                          {
    return computeImageBBox(makeNullPoint());
}

computeImageBBox() [2/2]

lsst::geom::Box2I Psf::computeImageBBox	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Return the bounding box of the image returned by computeImage()

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

Definition at line 149 of file Psf.cc.

                                                                                    {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    return doComputeImageBBox(position, color);
}

computeKernelBBox() [1/2]

lsst::geom::Box2I lsst::afw::detection::Psf::computeKernelBBox ( ) const

inline

Definition at line 332 of file Psf.h.

                                            {
        return computeBBox();
    }

computeKernelBBox() [2/2]

lsst::geom::Box2I lsst::afw::detection::Psf::computeKernelBBox ( lsst::geom::Point2D  position, image::Color  color = image::Color()  ) const

inline

Return the bounding box of the image returned by computeImage()

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor(). Alias for computeBBox

Definition at line 323 of file Psf.h.

                                                                               {
        return computeBBox(position, color);
    }

computeKernelImage() [1/2]

std::shared_ptr< Psf::Image > Psf::computeKernelImage

(

)

const

Definition at line 118 of file Psf.cc.

                                                      {
    return computeKernelImage(makeNullPoint());
}

computeKernelImage() [2/2]

std::shared_ptr< Psf::Image > Psf::computeKernelImage	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color(),
		ImageOwnerEnum	owner = COPY
	)		const

Return an Image of the PSF, in a form suitable for convolution.

While the position need not be an integer, the center of the PSF image returned by computeKernelImage will in the center of the center pixel of the image, which will be (0,0) when the Image's xy0 is taken into account; this is the same behavior as Kernel::computeImage().

The returned image is normalized to sum to unity.

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().
[in]	owner	Whether to copy the return value or return an internal image that must be handled with care (see ImageOwnerEnum).

The Psf class caches the most recent return value of computeKernelImage, so repeated calls with the same arguments will be highly optimized.

Note

The real work is done in the virtual private member function Psf::doComputeKernelImage; computeKernelImage only handles caching and default arguments.

Definition at line 122 of file Psf.cc.

                                                                                {
    if (_isFixed || isPointNull(position)) position = getAveragePosition();
    if (_isFixed || color.isIndeterminate()) color = getAverageColor();
    std::shared_ptr<Psf::Image> result = (*_kernelImageCache)(
            detail::PsfCacheKey(position, color),
            [this](detail::PsfCacheKey const &key) { return doComputeKernelImage(key.position, key.color); });
    if (owner == COPY) {
        result = std::make_shared<Image>(*result, true);
    }
    return result;
}

computePeak() [1/2]

double Psf::computePeak

(

)

const

Definition at line 168 of file Psf.cc.

                              {
    return computePeak(makeNullPoint());
}

computePeak() [2/2]

double Psf::computePeak	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Return the peak value of the PSF image.

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

This calls computeKernelImage internally, but because this will usually be cached, it shouldn't be expensive (but be careful not to accidentally call it with no arguments when you actually want to call it with the same arguments just used to call computeImage or computeKernelImage).

Definition at line 172 of file Psf.cc.

                                                                        {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    std::shared_ptr<Image> image = computeKernelImage(position, color, INTERNAL);
    return (*image)(-image->getX0(), -image->getY0());
}

computeShape() [1/2]

geom::ellipses::Quadrupole Psf::computeShape

(

)

const

Definition at line 189 of file Psf.cc.

                                               {
    return computeShape(makeNullPoint());
}

computeShape() [2/2]

geom::ellipses::Quadrupole Psf::computeShape	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Compute the ellipse corresponding to the second moments of the Psf.

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

The algorithm used to compute the moments is up to the derived class, and hence this method should not be used when a particular algorithm or weight function is required.

Definition at line 193 of file Psf.cc.

                                                                                         {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    return doComputeShape(position, color);
}

doComputeApertureFlux()

virtual double lsst::afw::detection::Psf::doComputeApertureFlux ( double  radius, lsst::geom::Point2D const &  position, image::Color const &  color  ) const

privatepure virtual

Implemented in lsst::meas::algorithms::ImagePsf.

doComputeBBox()

virtual lsst::geom::Box2I lsst::afw::detection::Psf::doComputeBBox ( lsst::geom::Point2D const &  position, image::Color const &  color  ) const

privatepure virtual

Implemented in lsst::meas::algorithms::CoaddPsf.

doComputeImage()

std::shared_ptr< Psf::Image > Psf::doComputeImage ( lsst::geom::Point2D const &  position, image::Color const &  color  ) const

protectedvirtual

These virtual members are protected (rather than private) so that python-implemented derived classes may opt to use the default implementations.

C++ derived classes may override these methods, but should not call them. Derived classes should call the corresponding compute* member functions instead so as to let the Psf base class handle caching properly.

Derived classes are responsible for ensuring that returned images sum to one.

Definition at line 199 of file Psf.cc.

                                                                               {
    std::shared_ptr<Psf::Image> im = computeKernelImage(position, color, COPY);
    return recenterKernelImage(im, position);
}

doComputeImageBBox()

lsst::geom::Box2I Psf::doComputeImageBBox ( lsst::geom::Point2D const &  position, image::Color const &  color  ) const

protectedvirtual

Definition at line 205 of file Psf.cc.

                                                                         {
    std::shared_ptr<Psf::Image> im = computeImage(position, color, INTERNAL);
    return im->getBBox();
}

doComputeKernelImage()

virtual std::shared_ptr<Image> lsst::afw::detection::Psf::doComputeKernelImage ( lsst::geom::Point2D const &  position, image::Color const &  color  ) const

privatepure virtual

These virtual member functions are private, not protected, because we only want derived classes to implement them, not call them; they should call the corresponding compute*Image member functions instead so as to let the Psf base class handle caching properly.

Derived classes are responsible for ensuring that returned images sum to one.

Implemented in lsst::meas::algorithms::WarpedPsf, and lsst::meas::algorithms::CoaddPsf.

doComputeShape()

virtual geom::ellipses::Quadrupole lsst::afw::detection::Psf::doComputeShape ( lsst::geom::Point2D const &  position, image::Color const &  color  ) const

privatepure virtual

Implemented in lsst::meas::algorithms::ImagePsf.

dynamicCast()

template std::shared_ptr< meas::extensions::psfex::PsfexPsf > lsst::afw::table::io::PersistableFacade< Psf >::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.

                                                                                        {
    auto result = std::dynamic_pointer_cast<T>(ptr);
    if (!result) {
        throw LSST_EXCEPT(pex::exceptions::TypeError, "Dynamic pointer cast failed");
    }
    return result;
}

equals()

bool lsst::afw::typehandling::Storable::equals ( Storable const &  other ) const

virtualnoexceptinherited

Compare this object to another Storable.

Subclasses that implement equality comparison must override this method to give results consistent with operator== for all inputs that are accepted by both.

Returns

This implementation returns whether the two objects are the same.

Warning

This method compares an object to any type of Storable, although cross-class comparisons should usually return false. If cross-class comparisons are valid, implementers should take care that they are symmetric and will give the same result no matter what the compile-time types of the left- and right-hand sides are.

See also

singleClassEquals

Note

When called on Python classes, this method delegates to __eq__ if it exists.

Reimplemented in lsst::afw::image::VisitInfo, lsst::afw::image::PhotoCalib, lsst::afw::geom::SkyWcs, lsst::afw::geom::polygon::Polygon, and lsst::afw::typehandling::StorableHelper< Base >.

Definition at line 48 of file Storable.cc.

{ return this == &other; }

getAverageColor()

image::Color lsst::afw::detection::Psf::getAverageColor ( ) const

inline

Return the average Color of the stars used to construct the Psf.

This is also the Color used to return an image if you don't specify a Color.

Definition at line 274 of file Psf.h.

{ return image::Color(); }

getAveragePosition()

lsst::geom::Point2D Psf::getAveragePosition ( ) const

virtual

Return the average position of the stars used to construct the Psf.

This is also the position used to return an image if you don't specify a position.

Reimplemented in lsst::meas::extensions::psfex::PsfexPsf, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::KernelPsf, and lsst::meas::algorithms::CoaddPsf.

Definition at line 211 of file Psf.cc.

{ return lsst::geom::Point2D(); }

getCacheCapacity()

std::size_t Psf::getCacheCapacity

(

)

const

Return the capacity of the caches.

Both the image and kernel image caches have the same capacity.

Definition at line 213 of file Psf.cc.

{ return _kernelImageCache->capacity(); }

getLocalKernel() [1/2]

std::shared_ptr< math::Kernel const > Psf::getLocalKernel

(

)

const

Definition at line 155 of file Psf.cc.

                                                          {
    return getLocalKernel(makeNullPoint());
}

getLocalKernel() [2/2]

std::shared_ptr< math::Kernel const > Psf::getLocalKernel	(	lsst::geom::Point2D	position,
		image::Color	color = image::Color()
	)		const

Return a FixedKernel corresponding to the Psf image at the given point.

Parameters

[in]	position	Position at which to evaluate the PSF.
[in]	color	Color of the source for which to evaluate the PSF; defaults to getAverageColor().

This is implemented by calling computeKernelImage, and is simply provided for convenience.

Definition at line 159 of file Psf.cc.

                                                                                {
    if (isPointNull(position)) position = getAveragePosition();
    if (color.isIndeterminate()) color = getAverageColor();
    // FixedKernel ctor will deep copy image, so we can use INTERNAL.
    std::shared_ptr<Image> image = computeKernelImage(position, color, INTERNAL);
    return std::make_shared<math::FixedKernel>(*image);
}

getPersistenceName()

std::string lsst::afw::table::io::Persistable::getPersistenceName ( ) const

protectedvirtualinherited

Return the unique name used to persist this object and look up its factory.

Must be less than ArchiveIndexSchema::MAX_NAME_LENGTH characters.

Reimplemented in lsst::meas::modelfit::Mixture, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::SingleGaussianPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::DoubleGaussianPsf, lsst::meas::algorithms::CoaddPsf, lsst::meas::algorithms::CoaddBoundedField, lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::math::WarpingControl, lsst::afw::math::NearestWarpingKernel, lsst::afw::math::BilinearWarpingKernel, lsst::afw::math::LanczosWarpingKernel, lsst::afw::math::TransformBoundedField, lsst::afw::math::ProductBoundedField, lsst::afw::math::PixelAreaBoundedField, lsst::afw::math::LinearCombinationKernel, lsst::afw::math::DeltaFunctionKernel, lsst::afw::math::AnalyticKernel, lsst::afw::math::FixedKernel, lsst::afw::math::Chebyshev1Function2< ReturnT >, lsst::afw::math::PolynomialFunction2< ReturnT >, lsst::afw::math::DoubleGaussianFunction2< ReturnT >, lsst::afw::math::GaussianFunction2< ReturnT >, lsst::afw::math::ChebyshevBoundedField, lsst::afw::image::VisitInfo, lsst::afw::image::PhotoCalib, lsst::afw::image::CoaddInputs, lsst::afw::geom::Transform< FromEndpoint, ToEndpoint >, lsst::afw::geom::Transform< afw::geom::Point2Endpoint, afw::geom::GenericEndpoint >, lsst::afw::geom::SkyWcs, lsst::afw::geom::polygon::Polygon, lsst::afw::detection::HeavyFootprint< ImagePixelT, MaskPixelT, VariancePixelT >, lsst::afw::detection::GaussianPsf, lsst::afw::detection::Footprint, lsst::afw::cameraGeom::DetectorCollection, and lsst::afw::image::FilterLabel.

Definition at line 34 of file Persistable.cc.

{ return std::string(); }

getPythonModule()

std::string lsst::afw::table::io::Persistable::getPythonModule ( ) const

protectedvirtualinherited

Return the fully-qualified Python module that should be imported to guarantee that its factory is registered.

Must be less than ArchiveIndexSchema::MAX_MODULE_LENGTH characters.

Will be ignored if empty.

Reimplemented in lsst::meas::modelfit::Mixture, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::CoaddPsf, lsst::meas::algorithms::CoaddBoundedField, lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::math::WarpingControl, lsst::afw::math::NearestWarpingKernel, lsst::afw::math::BilinearWarpingKernel, lsst::afw::math::LanczosWarpingKernel, lsst::afw::math::TransformBoundedField, lsst::afw::math::ProductBoundedField, lsst::afw::math::PixelAreaBoundedField, lsst::afw::math::Kernel, lsst::afw::math::Function< ReturnT >, lsst::afw::math::ChebyshevBoundedField, lsst::afw::image::TransmissionCurve, lsst::afw::image::CoaddInputs, lsst::afw::geom::Transform< FromEndpoint, ToEndpoint >, lsst::afw::geom::Transform< afw::geom::Point2Endpoint, afw::geom::GenericEndpoint >, lsst::afw::geom::SkyWcs, lsst::afw::detection::GaussianPsf, lsst::afw::detection::Footprint, lsst::afw::cameraGeom::DetectorCollection, and lsst::afw::image::FilterLabel.

Definition at line 36 of file Persistable.cc.

{ return std::string(); }

hash_value()

std::size_t lsst::afw::typehandling::Storable::hash_value ( ) const

virtualinherited

Return a hash of this object (optional operation).

Exceptions

UnsupportedOperationException

Thrown if this object is not hashable.

Note

C++ subclass authors are responsible for any associated specializations of std::hash.

When called on Python classes, this method delegates to __hash__ if it exists.

Reimplemented in lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::image::VisitInfo, lsst::afw::image::FilterLabel, and lsst::afw::geom::polygon::Polygon.

Definition at line 44 of file Storable.cc.

                                     {
    throw LSST_EXCEPT(UnsupportedOperationException, "Hashes are not supported.");
}

isPersistable()

virtual bool lsst::afw::table::io::Persistable::isPersistable ( ) const

inlinevirtualnoexceptinherited

Return true if this particular object can be persisted using afw::table::io.

Reimplemented in lsst::meas::modelfit::Mixture, lsst::meas::extensions::psfex::PsfexPsf, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::SingleGaussianPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::DoubleGaussianPsf, lsst::meas::algorithms::CoaddPsf, lsst::meas::algorithms::CoaddBoundedField, lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::math::WarpingControl, lsst::afw::math::NearestWarpingKernel, lsst::afw::math::BilinearWarpingKernel, lsst::afw::math::LanczosWarpingKernel, lsst::afw::math::TransformBoundedField, lsst::afw::math::ProductBoundedField, lsst::afw::math::PixelAreaBoundedField, lsst::afw::math::LinearCombinationKernel, lsst::afw::math::DeltaFunctionKernel, lsst::afw::math::AnalyticKernel, lsst::afw::math::FixedKernel, lsst::afw::math::Chebyshev1Function2< ReturnT >, lsst::afw::math::PolynomialFunction2< ReturnT >, lsst::afw::math::DoubleGaussianFunction2< ReturnT >, lsst::afw::math::GaussianFunction2< ReturnT >, lsst::afw::math::ChebyshevBoundedField, lsst::afw::image::VisitInfo, lsst::afw::image::PhotoCalib, lsst::afw::image::FilterLabel, lsst::afw::image::CoaddInputs, lsst::afw::image::ApCorrMap, lsst::afw::geom::Transform< FromEndpoint, ToEndpoint >, lsst::afw::geom::Transform< afw::geom::Point2Endpoint, afw::geom::GenericEndpoint >, lsst::afw::geom::SpanSet, lsst::afw::geom::SkyWcs, lsst::afw::geom::polygon::Polygon, lsst::afw::detection::GaussianPsf, lsst::afw::detection::Footprint, lsst::afw::cameraGeom::TransformMap, lsst::afw::cameraGeom::DetectorCollection, lsst::afw::cameraGeom::Detector, and lsst::afw::cameraGeom::Camera.

Definition at line 102 of file Persistable.h.

{ return false; }

operator=() [1/2]

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

delete

operator=() [2/2]

Psf& lsst::afw::detection::Psf::operator= ( Psf const &  )

delete

readFits() [1/3]

static std::shared_ptr<Psf > lsst::afw::table::io::PersistableFacade< Psf >::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.

                                                         {
        return dynamicCast(Persistable::_readFits(fitsfile));
    }

readFits() [2/3]

static std::shared_ptr<Psf > lsst::afw::table::io::PersistableFacade< Psf >::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.

                                                                                             {
        return dynamicCast(Persistable::_readFits(manager, hdu));
    }

readFits() [3/3]

static std::shared_ptr<Psf > lsst::afw::table::io::PersistableFacade< Psf >::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.

                                                                                           {
        return dynamicCast(Persistable::_readFits(fileName, hdu));
    }

recenterKernelImage()

std::shared_ptr< image::Image< double > > Psf::recenterKernelImage ( std::shared_ptr< Image >  im, lsst::geom::Point2D const &  position, std::string const &  warpAlgorithm = "lanczos5", unsigned int  warpBuffer = 5  )

static

Helper function for Psf::doComputeImage(): converts a kernel image (centered at (0,0) when xy0 is taken into account) to an image centered at position when xy0 is taken into account.

warpAlgorithm is passed to afw::math::makeWarpingKernel() and can be "nearest", "bilinear", or "lanczosN"

warpBuffer zero-pads the image before recentering. Recommended value is 1 for bilinear, N for lanczosN (note that it would be cleaner to infer this value from the warping algorithm but this would require mild API changes; same issue occurs in e.g. afw::math::offsetImage()).

The point with integer coordinates (0,0) in the source image (with xy0 taken into account) corresponds to the point position in the destination image. If position is not integer-valued then we will need to fractionally shift the image using interpolation.

Note: if fractional recentering is performed, then a new image will be allocated and returned. If not, then the original image will be returned (after setting XY0).

Definition at line 85 of file Psf.cc.

                                                                                        {
    // "ir" : (integer, residual)
    std::pair<int, double> const irX = image::positionToIndex(position.getX(), true);
    std::pair<int, double> const irY = image::positionToIndex(position.getY(), true);
 
    if (irX.second != 0.0 || irY.second != 0.0) {
        im = math::offsetImage(*im, irX.second, irY.second, warpAlgorithm, warpBuffer);
    }
 
    im->setXY0(irX.first + im->getX0(), irY.first + im->getY0());
    return im;
}

resized()

virtual std::shared_ptr<Psf> lsst::afw::detection::Psf::resized ( int  width, int  height  ) const

pure virtual

Return clone with specified kernel dimensions.

Parameters

[in]	width	Number of columns in pixels
[in]	height	Number of rows in pixels

Must be implemented by derived classes.

Implemented in lsst::meas::extensions::psfex::PsfexPsf, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::SingleGaussianPsf, lsst::meas::algorithms::PcaPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::DoubleGaussianPsf, lsst::meas::algorithms::CoaddPsf, and lsst::afw::detection::GaussianPsf.

setCacheCapacity()

void Psf::setCacheCapacity

(

std::size_t

capacity

)

Set the capacity of the caches.

Both the image and kernel image caches will be set to this capacity.

Definition at line 215 of file Psf.cc.

                                             {
    _imageCache->reserve(capacity);
    _kernelImageCache->reserve(capacity);
}

singleClassEquals()

template<class T >

static bool lsst::afw::typehandling::Storable::singleClassEquals ( T const &  lhs, Storable const &  rhs  )

inlinestaticprotectedinherited

Test if a Storable is of a particular class and equal to another object.

This method template simplifies implementations of equals that delegate to operator== without supporting cross-class comparisons.

Template Parameters

T	The class expected of the two objects to be compared.

Parameters

lhs,rhs

The objects to compare. Note that rhs need not be a T, while lhs must be.

Returns

true if rhs is a T and lhs == rhs; false otherwise.

Exception Safety

Provides the same level of exception safety as operator==. Most implementations of operator== do not throw.

Note

This method template calls operator== with both arguments of compile-time type T const&. Its use is not recommended if there would be any ambiguity as to which operator== gets picked by overload resolution.

This method template is typically called from equals as:

bool MyType::equals(Storable const& other) const noexcept {
    return singleClassEquals(*this, other);
}

Definition at line 151 of file Storable.h.

                                                                     {
        auto typedRhs = dynamic_cast<T const*>(&rhs);
        if (typedRhs != nullptr) {
            return lhs == *typedRhs;
        } else {
            return false;
        }
    }

toString()

std::string lsst::afw::typehandling::Storable::toString ( ) const

virtualinherited

Create a string representation of this object (optional operation).

Exceptions

UnsupportedOperationException

Thrown if this object does not have a string representation.

Note

When called on Python classes, this method delegates to __repr__.

Reimplemented in lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::image::VisitInfo, lsst::afw::image::PhotoCalib, lsst::afw::image::FilterLabel, lsst::afw::geom::SkyWcs, and lsst::afw::geom::polygon::Polygon.

Definition at line 40 of file Storable.cc.

                                   {
    throw LSST_EXCEPT(UnsupportedOperationException, "No string representation available.");
}

write()

void lsst::afw::table::io::Persistable::write ( OutputArchiveHandle &  handle ) const

protectedvirtualinherited

Write the object to one or more catalogs.

The handle object passed to this function provides an interface for adding new catalogs and adding nested objects to the same archive (while checking for duplicates). See OutputArchiveHandle for more information.

Reimplemented in lsst::afw::typehandling::StorableHelper< Base >, lsst::afw::image::FilterLabel, lsst::meas::modelfit::Mixture, lsst::meas::algorithms::WarpedPsf, lsst::meas::algorithms::SingleGaussianPsf, lsst::meas::algorithms::KernelPsf, lsst::meas::algorithms::DoubleGaussianPsf, lsst::meas::algorithms::CoaddPsf, lsst::meas::algorithms::CoaddBoundedField, lsst::afw::math::WarpingControl, lsst::afw::math::NearestWarpingKernel, lsst::afw::math::BilinearWarpingKernel, lsst::afw::math::LanczosWarpingKernel, lsst::afw::math::TransformBoundedField, lsst::afw::math::ProductBoundedField, lsst::afw::math::PixelAreaBoundedField, lsst::afw::math::LinearCombinationKernel, lsst::afw::math::DeltaFunctionKernel, lsst::afw::math::AnalyticKernel, lsst::afw::math::FixedKernel, lsst::afw::math::ChebyshevBoundedField, lsst::afw::image::VisitInfo, lsst::afw::image::PhotoCalib, lsst::afw::image::CoaddInputs, lsst::afw::geom::Transform< FromEndpoint, ToEndpoint >, lsst::afw::geom::Transform< afw::geom::Point2Endpoint, afw::geom::GenericEndpoint >, lsst::afw::geom::SkyWcs, lsst::afw::geom::polygon::Polygon, lsst::afw::detection::HeavyFootprint< ImagePixelT, MaskPixelT, VariancePixelT >, lsst::afw::detection::GaussianPsf, lsst::afw::detection::Footprint, lsst::afw::cameraGeom::DetectorCollection, lsst::afw::cameraGeom::Camera, lsst::meas::extensions::psfex::PsfexPsf, lsst::afw::math::Chebyshev1Function2< ReturnT >, lsst::afw::math::PolynomialFunction2< ReturnT >, lsst::afw::math::DoubleGaussianFunction2< ReturnT >, and lsst::afw::math::GaussianFunction2< ReturnT >.

Definition at line 38 of file Persistable.cc.

                                                   {
    assert(!isPersistable());
    throw LSST_EXCEPT(pex::exceptions::LogicError,
                      "afw::table-based persistence is not supported for this object.");
}

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 Function Documentation

operator<<()

std::ostream & operator<< ( std::ostream &  os, Storable const &  storable  )

related

Output operator for Storable.

Parameters

os	the desired output stream
storable	the object to print

Returns

a reference to os

Exceptions

UnsupportedOperationException

Thrown if storable does not have an implementation of Storable::toString.

Definition at line 174 of file Storable.h.

                                                                        {
    return os << storable.toString();
}

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-0.7.0/Linux64/afw/22.0.1-42-gca6935d93+ba5e5ca3eb/include/lsst/afw/detection/Psf.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-0.7.0/Linux64/afw/22.0.1-42-gca6935d93+ba5e5ca3eb/src/detection/Psf.cc
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-0.7.0/Linux64/meas_extensions_psfex/22.0.1-4-g3a563be+32dcf1063f/src/psfImpl.cc