lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT > Class Template Reference

Asseses the quality of a candidate given a spatial kernel and background model. More...

#include <AssessSpatialKernelVisitor.h>

Inheritance diagram for lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >:

Public Types
typedef boost::shared_ptr < AssessSpatialKernelVisitor < PixelT > >	Ptr

Public Member Functions
	AssessSpatialKernelVisitor (lsst::afw::math::LinearCombinationKernel::Ptr spatialKernel, lsst::afw::math::Kernel::SpatialFunctionPtr spatialBackground, lsst::pex::policy::Policy const &policy)
virtual	~AssessSpatialKernelVisitor ()
void	reset ()
int	getNGood ()
int	getNRejected ()
int	getNProcessed ()
void	processCandidate (lsst::afw::math::SpatialCellCandidate *candidate)
Public Member Functions inherited from lsst::afw::math::CandidateVisitor
	CandidateVisitor ()
virtual	~CandidateVisitor ()

Private Types
typedef lsst::afw::image::MaskedImage < PixelT >	MaskedImageT

Private Attributes
lsst::afw::math::LinearCombinationKernel::Ptr	_spatialKernel
	Spatial kernel function. More...
lsst::afw::math::Kernel::SpatialFunctionPtr	_spatialBackground
	Spatial background function. More...
lsst::pex::policy::Policy	_policy
	Policy controlling behavior. More...
ImageStatistics< PixelT >	_imstats
	To calculate statistics of difference image. More...
int	_nGood
	Number of good candidates remaining. More...
int	_nRejected
	Number of candidates rejected during processCandidate() More...
int	_nProcessed
	Number of candidates processed during processCandidate() More...
bool	_useCoreStats
	Extracted from policy. More...
int	_coreRadius
	Extracted from policy. More...

Detailed Description

template<typename PixelT>
class lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >

Asseses the quality of a candidate given a spatial kernel and background model.

   detail::AssessSpatialKernelVisitor<PixelT> spatialKernelAssessor(spatialKernel, 
                                                                    spatialBackground, 
                                                                    policy);
   spatialKernelAssessor.reset();
   kernelCells.visitCandidates(&spatialKernelAssessor, nStarPerCell);
   nRejected = spatialKernelAssessor.getNRejected();
* 

Note

Evaluates the spatial kernel and spatial background at the location of each candidate, and computes the resulting difference image. Sets candidate as afwMath::SpatialCellCandidate::GOOD/BAD if requested by the Policy.

Definition at line 26 of file AssessSpatialKernelVisitor.h.

Member Typedef Documentation

template<typename PixelT >

typedef lsst::afw::image::MaskedImage<PixelT> lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::MaskedImageT

private

Definition at line 27 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

typedef boost::shared_ptr<AssessSpatialKernelVisitor<PixelT> > lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::Ptr

Definition at line 29 of file AssessSpatialKernelVisitor.h.

Constructor & Destructor Documentation

template<typename PixelT >

lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::AssessSpatialKernelVisitor	(	lsst::afw::math::LinearCombinationKernel::Ptr	spatialKernel,
		lsst::afw::math::Kernel::SpatialFunctionPtr	spatialBackground,
		lsst::pex::policy::Policy const &	policy
	)

Parameters

spatialKernel	Spatially varying kernel
spatialBackground	Spatially varying background
policy	Policy file

Definition at line 55 of file AssessSpatialKernelVisitor.cc.

          : 
        afwMath::CandidateVisitor(),
        _spatialKernel(spatialKernel),
        _spatialBackground(spatialBackground),
        _policy(policy),
        _imstats(ImageStatistics<PixelT>(_policy)),
        _nGood(0),
        _nRejected(0),
        _nProcessed(0),
        _useCoreStats(_policy.getBool("useCoreStats")),
        _coreRadius(_policy.getInt("candidateCoreRadius"))
    {};

template<typename PixelT >

virtual lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::~AssessSpatialKernelVisitor ( )

inlinevirtual

Definition at line 36 of file AssessSpatialKernelVisitor.h.

{};

Member Function Documentation

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::getNGood ( )

inline

Definition at line 40 of file AssessSpatialKernelVisitor.h.

{return _nGood;}

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::getNProcessed ( )

inline

Definition at line 42 of file AssessSpatialKernelVisitor.h.

{return _nProcessed;}

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::getNRejected ( )

inline

Definition at line 41 of file AssessSpatialKernelVisitor.h.

{return _nRejected;}

template<typename PixelT >

void lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::processCandidate ( lsst::afw::math::SpatialCellCandidate *  candidate )

virtual

Reimplemented from lsst::afw::math::CandidateVisitor.

Definition at line 73 of file AssessSpatialKernelVisitor.cc.

          {
        
        KernelCandidate<PixelT> *kCandidate = dynamic_cast<KernelCandidate<PixelT> *>(candidate);
        if (kCandidate == NULL) {
            throw LSST_EXCEPT(pexExcept::LogicError,
                              "Failed to cast SpatialCellCandidate to KernelCandidate");
        }
        if (!(kCandidate->isInitialized())) {
            kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
            pexLogging::TTrace<3>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                  "Cannot process candidate %d, continuing", kCandidate->getId());
            return;
        }
        
        pexLogging::TTrace<2>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                              "Processing candidate %d", kCandidate->getId());

        /* 
           Note - this is a hack until the Kernel API is upgraded by the
           Davis crew.  I need a "local" version of the spatially varying
           Kernel
        */
        afwImage::Image<double> kImage(_spatialKernel->getDimensions());
        double kSum = _spatialKernel->computeImage(kImage, false, 
                                                   kCandidate->getXCenter(), kCandidate->getYCenter());
        boost::shared_ptr<afwMath::Kernel>
            kernelPtr(new afwMath::FixedKernel(kImage));
        /* </hack> */
        
        double background = (*_spatialBackground)(kCandidate->getXCenter(), kCandidate->getYCenter());
        
        MaskedImageT diffim = kCandidate->getDifferenceImage(kernelPtr, background);

        if (DEBUG_IMAGES) {
            kImage.writeFits(str(boost::format("askv_k%d.fits") % kCandidate->getId()));
            diffim.writeFits(str(boost::format("askv_d%d.fits") % kCandidate->getId()));
        }

        /* Official resids */
        try {
            if (_useCoreStats) 
                _imstats.apply(diffim, _coreRadius);
            else
                _imstats.apply(diffim);
        } catch (pexExcept::Exception& e) {
            pexLogging::TTrace<3>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                  "Unable to calculate imstats for Candidate %d", kCandidate->getId()); 
            kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
            return;
        }

        _nProcessed += 1;
        
        pexLogging::TTrace<5>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                              "Chi2 = %.3f", _imstats.getVariance());
        pexLogging::TTrace<5>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate",
                              "X = %.2f Y = %.2f",
                              kCandidate->getXCenter(), 
                              kCandidate->getYCenter());
        pexLogging::TTrace<5>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate",
                              "Kernel Sum = %.3f", kSum);
        pexLogging::TTrace<5>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate",
                              "Background = %.3f", background);
        pexLogging::TTrace<3>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate",
                              "Candidate %d resids = %.3f +/- %.3f sigma (%d pix)",
                              kCandidate->getId(),
                              _imstats.getMean(),
                              _imstats.getRms(),
                              _imstats.getNpix());
        
        bool meanIsNan = std::isnan(_imstats.getMean());
        bool rmsIsNan  = std::isnan(_imstats.getRms());
        if (meanIsNan || rmsIsNan) {
            kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
            pexLogging::TTrace<4>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                  "Rejecting candidate %d, encountered NaN",
                                  kCandidate->getId());
            _nRejected += 1;
            return;
        }
        
        if (_policy.getBool("spatialKernelClipping")) {            
            if (fabs(_imstats.getMean()) > _policy.getDouble("candidateResidualMeanMax")) {
                kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
                pexLogging::TTrace<4>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                      "Rejecting candidate %d; bad mean residual : |%.3f| > %.3f",
                                      kCandidate->getId(),
                                      _imstats.getMean(),
                                      _policy.getDouble("candidateResidualMeanMax"));
                _nRejected += 1;
            }
            else if (_imstats.getRms() > _policy.getDouble("candidateResidualStdMax")) {
                kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
                pexLogging::TTrace<4>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                      "Rejecting candidate %d; bad residual rms : %.3f > %.3f",
                                      kCandidate->getId(),
                                      _imstats.getRms(),
                                      _policy.getDouble("candidateResidualStdMax"));
                _nRejected += 1;
            }
            else {
                kCandidate->setStatus(afwMath::SpatialCellCandidate::GOOD);
                pexLogging::TTrace<4>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                      "Spatial kernel OK");
                _nGood += 1;
            }
        }
        else {
            kCandidate->setStatus(afwMath::SpatialCellCandidate::GOOD);
            pexLogging::TTrace<6>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                  "Sigma clipping not enabled");
            _nGood += 1;
        }

        /* Core resids for debugging */
        if (!(_useCoreStats)) {
            try {
                _imstats.apply(diffim, _coreRadius);
            } catch (pexExcept::Exception& e) {
                pexLogging::TTrace<3>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate", 
                                      "Unable to calculate core imstats for Candidate %d", 
                                      kCandidate->getId()); 
                kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
                return;
            }
            pexLogging::TTrace<4>("lsst.ip.diffim.AssessSpatialKernelVisitor.processCandidate",
                                  "Candidate %d core resids = %.3f +/- %.3f sigma (%d pix)",
                                  kCandidate->getId(),
                                  _imstats.getMean(),
                                  _imstats.getRms(),
                                  _imstats.getNpix());
        }
    }

template<typename PixelT >

void lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::reset ( )

inlinevirtual

Reimplemented from lsst::afw::math::CandidateVisitor.

Definition at line 38 of file AssessSpatialKernelVisitor.h.

{_nGood = 0; _nRejected = 0; _nProcessed = 0;}

Member Data Documentation

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_coreRadius

private

Extracted from policy.

Definition at line 55 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

ImageStatistics<PixelT> lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_imstats

private

To calculate statistics of difference image.

Definition at line 49 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_nGood

private

Number of good candidates remaining.

Definition at line 50 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_nProcessed

private

Number of candidates processed during processCandidate()

Definition at line 52 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

int lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_nRejected

private

Number of candidates rejected during processCandidate()

Definition at line 51 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

lsst::pex::policy::Policy lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_policy

private

Policy controlling behavior.

Definition at line 48 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

lsst::afw::math::Kernel::SpatialFunctionPtr lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_spatialBackground

private

Spatial background function.

Definition at line 47 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

lsst::afw::math::LinearCombinationKernel::Ptr lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_spatialKernel

private

Spatial kernel function.

Definition at line 46 of file AssessSpatialKernelVisitor.h.

template<typename PixelT >

bool lsst::ip::diffim::detail::AssessSpatialKernelVisitor< PixelT >::_useCoreStats

private

Extracted from policy.

Definition at line 54 of file AssessSpatialKernelVisitor.h.

---

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

• /home/lsstsw/stack/Linux64/ip_diffim/11.0+1/include/lsst/ip/diffim/AssessSpatialKernelVisitor.h
• /home/lsstsw/stack/Linux64/ip_diffim/11.0+1/src/AssessSpatialKernelVisitor.cc