ExposureInfo.cc

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// -*- LSST-C++ -*- // fixed format comment for emacs
/* 
 * LSST Data Management System
 * Copyright 2008, 2009, 2010 LSST Corporation.
 * 
 * This product includes software developed by the
 * LSST Project (http://www.lsst.org/).
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the LSST License Statement and 
 * the GNU General Public License along with this program.  If not, 
 * see <http://www.lsstcorp.org/LegalNotices/>.
 */

#include "lsst/pex/exceptions.h"
#include "lsst/pex/logging/Log.h"
#include "lsst/afw/image/ExposureInfo.h"
#include "lsst/afw/image/Calib.h"
#include "lsst/afw/image/Wcs.h"
#include "lsst/afw/detection/Psf.h"
#include "lsst/afw/cameraGeom/Detector.h"
#include "lsst/afw/fits.h"

namespace lsst { namespace afw { namespace image {

namespace {

// Return an int value from a PropertySet if it exists and remove it, or return 0.
int popInt(daf::base::PropertySet & metadata, std::string const & name) {
    int r = 0;
    if (metadata.exists(name)) {
        r = metadata.get<int>(name);
        metadata.remove(name);
    }
    return r;
}

} // anonymous


// Clone various components; defined here so that we don't have to expose their insides in Exposure.h

PTR(Calib) ExposureInfo::_cloneCalib(CONST_PTR(Calib) calib) {
    if (calib)
        return PTR(Calib)(new Calib(*calib));
    return PTR(Calib)();
}

PTR(Wcs) ExposureInfo::_cloneWcs(CONST_PTR(Wcs) wcs) {
    if (wcs)
        return wcs->clone();
    return PTR(Wcs)();
}

ExposureInfo::ExposureInfo(
    CONST_PTR(Wcs) const & wcs,
    CONST_PTR(detection::Psf) const & psf,
    CONST_PTR(Calib) const & calib,
    CONST_PTR(cameraGeom::Detector) const & detector,
    Filter const & filter,
    PTR(daf::base::PropertySet) const & metadata,
    PTR(CoaddInputs) const & coaddInputs
) : _wcs(_cloneWcs(wcs)),
    _psf(boost::const_pointer_cast<detection::Psf>(psf)),
    _calib(calib ? _cloneCalib(calib) : PTR(Calib)(new Calib())),
    _detector(detector),
    _filter(filter),
    _metadata(metadata ? metadata : PTR(daf::base::PropertySet)(new daf::base::PropertyList())),
    _coaddInputs(coaddInputs)
{}

ExposureInfo::ExposureInfo(ExposureInfo const & other) : 
    _wcs(_cloneWcs(other._wcs)),
    _psf(other._psf),
    _calib(_cloneCalib(other._calib)),
    _detector(other._detector),
    _filter(other._filter),
    _metadata(other._metadata),
    _coaddInputs(other._coaddInputs)
{}

ExposureInfo::ExposureInfo(ExposureInfo const & other, bool copyMetadata) :
    _wcs(_cloneWcs(other._wcs)),
    _psf(other._psf),
    _calib(_cloneCalib(other._calib)),
    _detector(other._detector),
    _filter(other._filter),
    _metadata(other._metadata),
    _coaddInputs(other._coaddInputs)
{
    if (copyMetadata) _metadata = _metadata->deepCopy();
}

ExposureInfo & ExposureInfo::operator=(ExposureInfo const & other) {
    if (&other != this) {
        _wcs = _cloneWcs(other._wcs);
        _psf = other._psf;
        _calib = _cloneCalib(other._calib);
        _detector = other._detector;
        _filter = other._filter;
        _metadata = other._metadata;
        _coaddInputs = other._coaddInputs;
    }
    return *this;
}

ExposureInfo::~ExposureInfo() {}

ExposureInfo::FitsWriteData
ExposureInfo::_startWriteFits(afw::geom::Point2I const & xy0) const {
    
    FitsWriteData data;

    data.metadata.reset(new daf::base::PropertyList());
    data.imageMetadata.reset(new daf::base::PropertyList());
    data.maskMetadata = data.imageMetadata;
    data.varianceMetadata = data.imageMetadata;

    data.metadata->combine(getMetadata());

    // In the future, we might not have exactly three image HDUs, but we always do right now,
    // so 1=primary, 2=image, 3=mask, 4=variance, 5+=archive
    data.metadata->set("AR_HDU", 5, "HDU containing the archive used to store ancillary objects");
    if (hasCoaddInputs()) {
        int coaddInputsId = data.archive.put(getCoaddInputs());
        data.metadata->set("COADD_INPUTS_ID", coaddInputsId, "archive ID for coadd inputs catalogs");
    }
    if (hasPsf() && getPsf()->isPersistable()) {
        int psfId = data.archive.put(getPsf());
        data.metadata->set("PSF_ID", psfId, "archive ID for the Exposure's main Psf");
    }
    if (hasWcs() && getWcs()->isPersistable()) {
        int wcsId = data.archive.put(getWcs());
        data.metadata->set("WCS_ID", wcsId, "archive ID for the Exposure's main Wcs");
    }

    //LSST convention is that Wcs is in pixel coordinates (i.e relative to bottom left
    //corner of parent image, if any). The Wcs/Fits convention is that the Wcs is in
    //image coordinates. When saving an image we convert from pixel to index coordinates.
    //In the case where this image is a parent image, the reference pixels are unchanged
    //by this transformation
    if (hasWcs()) {
        PTR(Wcs) newWcs = getWcs()->clone(); //Create a copy
        newWcs->shiftReferencePixel(-xy0.getX(), -xy0.getY() );

        // We want the WCS to appear in all HDUs
        data.imageMetadata->combine(newWcs->getFitsMetadata());
    }

    //Store _x0 and _y0. If this exposure is a portion of a larger image, _x0 and _y0
    //indicate the origin (the position of the bottom left corner) of the sub-image with
    //respect to the origin of the parent image.
    //This is stored in the fits header using the LTV convention used by STScI
    //(see \S2.6.2 of HST Data Handbook for STIS, version 5.0
    // http://www.stsci.edu/hst/stis/documents/handbooks/currentDHB/ch2_stis_data7.html#429287).
    //This is not a fits standard keyword, but is recognised by ds9
    //LTV keywords use the opposite convention to the LSST, in that they represent
    //the position of the origin of the parent image relative to the origin of the sub-image.
    // _x0, _y0 >= 0, while LTV1 and LTV2 <= 0
  
    data.imageMetadata->set("LTV1", -xy0.getX());
    data.imageMetadata->set("LTV2", -xy0.getY());

    data.metadata->set("FILTER", getFilter().getName());
    if (hasDetector()) {
        data.metadata->set("DETNAME", getDetector()->getName());
        data.metadata->set("DETSER", getDetector()->getSerial());
    }
    data.metadata->set("TIME-MID", getCalib()->getMidTime().toString());
    data.metadata->set("EXPTIME", getCalib()->getExptime());
    data.metadata->set("FLUXMAG0", getCalib()->getFluxMag0().first);
    data.metadata->set("FLUXMAG0ERR", getCalib()->getFluxMag0().second);
    
    return data;
}

void ExposureInfo::_finishWriteFits(fits::Fits & fitsfile, FitsWriteData const & data) const {
    data.archive.writeFits(fitsfile);
}

void ExposureInfo::_readFits(
    fits::Fits & fitsfile,
    PTR(daf::base::PropertySet) metadata,
    PTR(daf::base::PropertySet) imageMetadata
) {
    // true: strip keywords that are related to the created WCS from the input metadata
    _wcs = makeWcs(imageMetadata, true);

    if (!imageMetadata->exists("INHERIT")) {
        // New-style exposures put everything but the Wcs in the primary HDU, use
        // INHERIT keyword in the others.  For backwards compatibility, if we don't
        // find the INHERIT keyword, we ignore the primary HDU metadata and expect
        // everything to be in the image HDU metadata.  Note that we can't merge them,
        // because they're probably duplicates.
        metadata = imageMetadata;
    }

    _filter = Filter(metadata, true);
    detail::stripFilterKeywords(metadata);

    PTR(Calib) newCalib(new Calib(metadata));
    setCalib(newCalib);
    detail::stripCalibKeywords(metadata);

    int archiveHdu = popInt(*metadata, "AR_HDU");

    if (archiveHdu) {
        fitsfile.setHdu(archiveHdu);
        table::io::InputArchive archive = table::io::InputArchive::readFits(fitsfile);
        // Load the Psf and Wcs from the archive; id=0 results in a null pointer.
        // Note that the binary table Wcs, if present, clobbers the FITS header one,
        // because the former might be an approximation to something we can't represent
        // using the FITS WCS standard but can represent with binary tables.
        int psfId = popInt(*metadata, "PSF_ID");
        try {
            _psf = archive.get<detection::Psf>(psfId);
        } catch (pex::exceptions::NotFoundError & err) {
            pex::logging::Log::getDefaultLog().warn(
                boost::format("Could not read PSF; setting to null: %s") % err.what()
            );
        }
        int wcsId = popInt(*metadata, "WCS_ID");
        try {
            _wcs = archive.get<Wcs>(wcsId);
        } catch (pex::exceptions::NotFoundError & err) {
            pex::logging::Log::getDefaultLog().warn(
                boost::format("Could not read WCS; setting to null: %s") % err.what()
            );
        }
        int coaddInputsId = popInt(*metadata, "COADD_INPUTS_ID");
        try {
            _coaddInputs = archive.get<CoaddInputs>(coaddInputsId);
        } catch (pex::exceptions::NotFoundError & err) {
            pex::logging::Log::getDefaultLog().warn(
                boost::format("Could not read CoaddInputs; setting to null: %s") % err.what()
            );
        }
    }

    _metadata = metadata;
}

}}} // namespace lsst::afw::image