casa6

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//# Associated Universities, Inc. Washington DC, USA.

//#

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//# $Id: $

​

#include <imageanalysis/ImageAnalysis/ImageRegridder.h>

​

#include <imageanalysis/ImageAnalysis/ImageFactory.h>

#include <imageanalysis/ImageAnalysis/ImageMetaData.h>

#include <imageanalysis/ImageAnalysis/SubImageFactory.h>

#include <casacore/images/Images/ImageConcat.h>

#include <casacore/images/Images/ImageRegrid.h>

#include <casacore/scimath/Mathematics/Geometry.h>

​

#include <casacore/casa/BasicSL/STLIO.h>

#include <memory>

​

namespace casa {

​

template<class T> const String  ImageRegridder<T>::_class = "ImageRegridder";

​

template<class T> ImageRegridder<T>::ImageRegridder(

    const SPCIIT image, const casacore::Record *const regionRec,

    const casacore::String& maskInp, const casacore::String& outname,

    casacore::Bool overwrite, const casacore::CoordinateSystem& csysTo,

    const casacore::IPosition& axes, const casacore::IPosition& shape

) : ImageRegridderBase<T>(

        image, regionRec, maskInp, outname,

        overwrite, csysTo, axes, shape

    ), _debug(0) {}

​

template<class T> ImageRegridder<T>::ImageRegridder(

    const SPCIIT image, const casacore::String& outname,

    const SPCIIT templateIm, const casacore::IPosition& axes,

    const casacore::Record *const regionRec, const casacore::String& maskInp,

    casacore::Bool overwrite, const casacore::IPosition& shape

)  : ImageRegridderBase<T>(

        image, regionRec, maskInp, outname, overwrite,

        templateIm->coordinates(), axes, shape

    ),

    _debug(0) {}

​

template<class T> ImageRegridder<T>::~ImageRegridder() {}

​

template<class T> SPIIT ImageRegridder<T>::regrid() const {

    _subimage = SubImageFactory<T>::createImage(

        *this->_getImage(), "", *this->_getRegion(), this->_getMask(),

        this->_getDropDegen(), false, false, this->_getStretch()

    );

    auto regridByVel = false;

    const auto axes = this->_getAxes();

    auto hasMultipleBeams = this->_getImage()->imageInfo().hasMultipleBeams();

    const auto& csys = this->_getImage()->coordinates();

    if (

        (this->_getSpecAsVelocity() || hasMultipleBeams)

        && csys.hasSpectralAxis()

        && this->_getTemplateCoords().hasSpectralAxis()

    ) {

        auto inputSpecAxis = csys.spectralAxisNumber(false);

        auto isInputSpecDegen = _subimage->shape()[inputSpecAxis] == 1;

        if (axes.empty()) {

            ThrowIf(

                hasMultipleBeams,

                "An image with multiple beams cannot be regridded along the "

                "spectral axis. You may wish to convolve all channels to a "

                "common resolution and retry"

            );

            if (! isInputSpecDegen && this->_getSpecAsVelocity()) {

                regridByVel = true;

            }