Image2DConvolver.h

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//# Image2DConvolver.h: 2D convolution of an image
//# Copyright (C) 1996,1997,1998,1999,2000,2001,2002,2003
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 of the License, or (at your
//# option) any later version.
//#
//# This library 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 Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//#        Internet email: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
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//#
//# $Id: Image2DConvolver.h 20229 2008-01-29 15:19:06Z gervandiepen $

#ifndef IMAGES_IMAGE2DCONVOLVER_H
#define IMAGES_IMAGE2DCONVOLVER_H


//# Includes
#include <casa/aips.h>
#include <casa/Logging/LogIO.h>
#include <casa/Arrays/Array.h>
#include <scimath/Mathematics/VectorKernel.h>
#include <casa/Quanta/Quantum.h>

namespace casa { //# NAMESPACE CASA - BEGIN

//# Forward Declarations
template <class T> class ImageInterface;
template <class T> class Matrix;
template <class T> class Vector;
class String;
class IPosition;
class CoordinateSystem;
class ImageInfo;
class Unit;
class GaussianBeam;


// <summary>
// This class does 2D convolution of an image by a functional form
// </summary>

// <use visibility=export>

// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
// </reviewed>

// <prerequisite>
//   <li> <linkto class="ImageInterface">ImageInterface</linkto>
//   <li> <linkto class="Convolver">Convolver</linkto>
// </prerequisite>

// <etymology>
// This class handles 2D convolution of images 
// </etymology>

// <synopsis>
// This class convolves an image by a specified 2D function.
// </synopsis>

// <example>
// <srcBlock>
// </srcBlock>
// </example>

// <motivation>
// Convolution is a standard image processing requirement.  The
// class object has no state.
// The convolution is done via FFT.  Thus input pixels which
// are masked are set to 0 before the convolution.  The mask
// is transferred to the output image.  No additional scaling
// of the output image values is done.
// 
// </motivation>

// <todo asof="2001/08/28">
//   <li> 
// </todo>
 

template <class T> class Image2DConvolver
{
public:

        // Convolve.   If the output image needs a mask and doesn't have one,
        // it will be given one if possible.  The miscInfo, imageInfo,
        // units and logger will be copied from the input to the output
        // unless you indicate not to (copyMiscellaneous).
        static void convolve(
                LogIO& os, ImageInterface<T>& imageOut,
                const ImageInterface<T>& imageIn,
                const VectorKernel::KernelTypes kernelType,
                const IPosition& pixelAxes,
                const Vector<Quantity>& parameters,
                const Bool autoScale, const Double scale,
                const Bool copyMiscellaneous=True,
                const Bool targetres=False
        );

private:

        // This class contains all static methods. Do not allow it to
        // be instantiated.
        // Constructor
        Image2DConvolver ();

        // Copy constructor.  Uses reference semantics.
        Image2DConvolver(const Image2DConvolver<T> &other);

        // Destructor
        ~Image2DConvolver();

        // Assignment operator. Uses reference semantics.
        Image2DConvolver &operator=(const Image2DConvolver<T> &other);


        static void _checkKernelParameters(
                LogIO& os, VectorKernel::KernelTypes kernelType,
                const Vector<Quantum<Double> >& parameters
        );

        static void _dealWithRestoringBeam (
                LogIO& os, String& brightnessUnitOut, GaussianBeam& beamOut,
                Array<T>& kernelArray, const T kernelVolume,
                const VectorKernel::KernelTypes kernelType,
                const Vector<Quantity>& parameters,
                const IPosition& axes, const CoordinateSystem& cSys,
                const GaussianBeam& beamIn, const Unit& brightnessUnit,
                const Bool autoscale, const Double scale, const Bool emitMessage
        );

        static T _fillKernel (
                Matrix<T>& kernelMatrix,
                VectorKernel::KernelTypes kernelType,
                const IPosition& kernelShape,
                const IPosition& axes,
                const Vector<Double>& parameters
        );

        static void fillGaussian(
                T& maxVal, T& volume, Matrix<T>& pixels,
                T height, T xCentre, T yCentre,
                T majorAxis, T ratio, T positionAngle
        );

        static T _makeKernel(
                LogIO& os, Array<T>& kernel,
                VectorKernel::KernelTypes kernelType,
                const Vector<Quantity>& parameters,
                const IPosition& axes,
                const ImageInterface<T>& inImage
        );

        static IPosition shapeOfKernel(
                const VectorKernel::KernelTypes kernelType,
                const Vector<Double>& parameters,
                const uInt ndim, const IPosition& axes
        );

        static uInt sizeOfGaussian(const Double width, const Double nSigma);

        static Vector<Quantity> _getConvolvingBeamForTargetResolution(
                LogIO& os, const Vector<Quantity>& targetBeamParms,
                const GaussianBeam& inputBeam
        );
};



} //# NAMESPACE CASA - END

#ifndef CASACORE_NO_AUTO_TEMPLATES
#include <imageanalysis/ImageAnalysis/Image2DConvolver.tcc>
#endif //# CASACORE_NO_AUTO_TEMPLATES
#endif