FITSImage.h

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// # FITSImage.h: Class providing native access to FITS images
// # Copyright (C) 2001,2002
// # 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: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef IMAGES_FITSIMAGE_H
#define IMAGES_FITSIMAGE_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/Arrays/ArrayFwd.h>
#include <casacore/images/Images/ImageInterface.h>
#include <casacore/images/Images/MaskSpecifier.h>
#include <casacore/tables/DataMan/TiledFileAccess.h>
#include <casacore/lattices/Lattices/TiledShape.h>
#include <casacore/fits/FITS/fits.h>
#include <casacore/casa/BasicSL/String.h>
#include <casacore/casa/Utilities/DataType.h>
 
#ifndef WCSLIB_GETWCSTAB
#define WCSLIB_GETWCSTAB
#endif
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward Declarations
template <class T>
class Lattice;
//
class MaskSpecifier;
class IPosition;
class Slicer;
class CoordinateSystem;
class FITSMask;
class FitsInput;
 
// <summary>
// Class providing native access to FITS images.
// </summary>
 
// <use visibility=export>
 
// <reviewed reviewer="" date="" tests="tFITSImage.cc">
// </reviewed>
 
// <prerequisite>
//   <li> <linkto class=ImageInterface>ImageInterface</linkto>
//   <li> <linkto class=FITSMask>FITSMask</linkto>
// </prerequisite>
 
// <etymology>
//  This class provides native access to FITS images.
//  64bit, 32bit floating point, 32 bit and 16bit integer FITS images are
//  presently supported.
// </etymology>
 
// <synopsis>
//  A FITSImage provides native access to FITS images by accessing them
//  with the TiledFileAccess class.  The FITSImage is read only.
//  We could implement a writable FITSImage but putting the mask
//  would lose data values (uses magic blanking) and FITS is really
//  meant as an interchange medium, not an internal format.
//
//  Because FITS uses magic value blanking, the mask is generated
//  on the fly as needed.
// </synopsis>
 
// <example>
// <srcblock>
//    FITSImage im("in.fits");
//    LogIO logger(or);
//    ImageStatistics<Float> stats(im, logger);
//    Bool ok = stats.display();                              // Display statistics
// </srcblock>
// </example>
 
// <motivation>
// This provides native access to FITS images.
// </motivation>
 
// # <todo asof="2001/02/09">
// # </todo>
 
class FITSImage : public ImageInterface<Float> {
 public:
  // Construct a FITSImage from the disk FITS file name  and extension and apply mask.
  explicit FITSImage(const String& name, uInt whichRep = 0, uInt whichHDU = 0);
 
  // Construct a FITSImage from the disk FITS file name and extension and apply mask or not.
  FITSImage(const String& name, const MaskSpecifier& mask, uInt whichRep = 0, uInt whichHDU = 0);
 
  // Copy constructor (reference semantics)
  FITSImage(const FITSImage& other);
 
  // Destructor does nothing
  virtual ~FITSImage() = default;
 
  // Assignment (reference semantics)
  FITSImage& operator=(const FITSImage& other);
 
  // Function to open a FITS image (new parser)
  static LatticeBase* openFITSImage(const String& name, const MaskSpecifier&);
 
  // Register the open function.
  static void registerOpenFunction();
 
  // Separate any extension specification and return the pure fitsname
  static String get_fitsname(const String& fullname);
 
  // Get the extension index for any extension specification given in the full name
  static uInt get_hdunum(const String& fullname);
 
  // # ImageInterface virtual functions
 
  // Make a copy of the object with new (reference semantics).
  virtual ImageInterface<Float>* cloneII() const;
 
  // Get the image type (returns FITSImage).
  virtual String imageType() const;
 
  // returns "FITSImage". Added so callers don't require an object to get
  // the image type.
  static String className();
 
  // Function which changes the shape of the FITSImage.
  // Throws an exception as FITSImage is not writable.
  virtual void resize(const TiledShape& newShape);
 
  // # MaskedLattice virtual functions
 
  // Has the object really a mask?  The FITSImage always
  // has a pixel mask and never has a region mask so this
  // always returns True
  virtual Bool isMasked() const;
 
  // FITSimage always has a pixel mask so returns True
  virtual Bool hasPixelMask() const;
 
  // Get access to the pixelmask.  FITSImage always has a pixel mask.
  // <group>
  virtual const Lattice<Bool>& pixelMask() const;
  virtual Lattice<Bool>& pixelMask();
  // </group>
 
  // Do the actual get of the mask data.   The return value is always
  // False, thus the buffer does not reference another array.
  virtual Bool doGetMaskSlice(Array<Bool>& buffer, const Slicer& section);
 
  // Get the region used.  There is no region.
  // Always returns 0.
  virtual const LatticeRegion* getRegionPtr() const;
 
  // # Lattice virtual functions
 
  // Do the actual get of the data.
  // Returns False as the data do not reference another Array
  virtual Bool doGetSlice(Array<Float>& buffer, const Slicer& theSlice);
 
  // The FITSImage is not writable, so this throws an exception.
  virtual void doPutSlice(const Array<Float>& sourceBuffer, const IPosition& where,
                          const IPosition& stride);
 
  // # LatticeBase virtual functions
 
  // The lattice is paged to disk.
  virtual Bool isPaged() const;
 
  // The lattice is persistent.
  virtual Bool isPersistent() const;
 
  // The FITSImage is not writable.
  virtual Bool isWritable() const;
 
  // Returns the name of the disk file.
  virtual String name(Bool stripPath = False) const;
 
  // return the shape of the FITSImage
  virtual IPosition shape() const;
 
  // Returns the maximum recommended number of pixels for a cursor. This is
  // the number of pixels in a tile.
  virtual uInt advisedMaxPixels() const;
 
  // Help the user pick a cursor for most efficient access if they only want
  // pixel values and don't care about the order or dimension of the
  // cursor.
  virtual IPosition doNiceCursorShape(uInt maxPixels) const;
 
  // Temporarily close the image.
  virtual void tempClose();
 
  // Reopen a temporarily closed image.
  virtual void reopen();
 
  // Check class invariants.
  virtual Bool ok() const;
 
  // Return the data type (TpFloat).
  virtual DataType dataType() const;
 
  // Return the (internal) data type.
  DataType internalDataType() const { return dataType_p; }
 
  // Return the HDU number
  uInt whichHDU() const { return whichHDU_p; }
 
  // Maximum size - not necessarily all used. In pixels.
  virtual uInt maximumCacheSize() const;
 
  // Set the maximum (allowed) cache size as indicated.
  virtual void setMaximumCacheSize(uInt howManyPixels);
 
  // Set the cache size as to "fit" the indicated path.
  virtual void setCacheSizeFromPath(const IPosition& sliceShape, const IPosition& windowStart,
                                    const IPosition& windowLength, const IPosition& axisPath);
 
  // Set the actual cache size for this Array to be be big enough for the
  // indicated number of tiles. This cache is not shared with PagedArrays
  // in other rows and is always clipped to be less than the maximum value
  // set using the setMaximumCacheSize member function.
  // tiles. Tiles are cached using a first in first out algorithm.
  virtual void setCacheSizeInTiles(uInt howManyTiles);
 
  // Clears and frees up the caches, but the maximum allowed cache size is
  // unchanged from when setCacheSize was called
  virtual void clearCache();
 
  // Report on cache success.
  virtual void showCacheStatistics(ostream& os) const;
 
 protected:
  // Set the masking of values 0.0
  void setMaskZero(Bool filterZero);
 
 private:
  String name_p;
  String fullname_p;
  MaskSpecifier maskSpec_p;
  std::shared_ptr<TiledFileAccess> pTiledFile_p;
  std::unique_ptr<Lattice<Bool>> pPixelMask_p;
  TiledShape shape_p;
  Float scale_p;
  Float offset_p;
  Short shortMagic_p;
  uChar uCharMagic_p;
  Int longMagic_p;
  Bool hasBlanks_p;
  DataType dataType_p;
  Int64 fileOffset_p;
  Bool isClosed_p;
  Bool filterZeroMask_p;
  uInt whichRep_p;
  uInt whichHDU_p;
  Bool _hasBeamsTable;
 
  // Reopen the image if needed.
  void reopenIfNeeded() const {
    if (isClosed_p) const_cast<FITSImage*>(this)->reopen();
  }
 
  // Setup the object (used by constructors).
  void setup();
 
  // Open the image (used by setup and reopen).
  void open();
 
  // Fish things out of the FITS file
  void getImageAttributes(CoordinateSystem& cSys, IPosition& shape, ImageInfo& info,
                          Unit& brightnessUnit, RecordInterface& miscInfo, Int& recsize, Int& recno,
                          FITS::ValueType& dataType, Float& scale, Float& offset, uChar& uCharMagic,
                          Short& shortMagic, Int& longMagic, Bool& hasBlanks, const String& name,
                          uInt whichRep, uInt whichHDU);
 
  // Crack a primary header
  template <typename T>
  void crackHeader(CoordinateSystem& cSys, IPosition& shape, ImageInfo& imageInfo,
                   Unit& brightnessUnit, RecordInterface& miscInfo, Float& scale, Float& offset,
                   uChar& magicUChar, Short& magicShort, Int& magicLong, Bool& hasBlanks, LogIO& os,
                   FitsInput& infile, uInt whichRep);
 
  // Crack an image extension header
  template <typename T>
  void crackExtHeader(CoordinateSystem& cSys, IPosition& shape, ImageInfo& imageInfo,
                      Unit& brightnessUnit, RecordInterface& miscInfo, Float& scale, Float& offset,
                      uChar& uCharMagic, Short& magicShort, Int& magicLong, Bool& hasBlanks,
                      LogIO& os, FitsInput& infile, uInt whichRep);
};
 
}  // namespace casacore
 
#ifndef CASACORE_NO_AUTO_TEMPLATES
#include <casacore/images/Images/FITS2Image.tcc>
#endif  // # CASACORE_NO_AUTO_TEMPLATES
 
#endif