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casa::FITSMask Class Reference

Provides an on-the-fly mask for FITS images. More...

#include <FITSMask.h>

Inheritance diagram for casa::FITSMask:
casa::Lattice< Bool > casa::LatticeBase

List of all members.

Public Member Functions

 FITSMask (TiledFileAccess *tiledFileAccess)
 Constructor (for 32 bit floating point).
 FITSMask (TiledFileAccess *tiledFileAccess, Float scale, Float offset, Short magic, Bool hasBlanks)
 Constructor (for 16 bit integers).
 FITSMask (TiledFileAccess *tiledFileAccess, Float scale, Float offset, Int magic, Bool hasBlanks)
 Constructor (for 32 bit integers).
 FITSMask (const FITSMask &other)
 Copy constructor (reference semantics).
virtual ~FITSMask ()
 Destructor.
FITSMaskoperator= (const FITSMask &other)
 The assignment operator with reference semantics.
virtual Lattice< Bool > * clone () const
 Make a copy of the object (reference semantics).
virtual Bool isWritable () const
 Is the FITSMask writable? Returns False.
IPosition shape () const
 Return the shape of the Lattice including all degenerate axes (ie.
virtual Bool doGetSlice (Array< Bool > &buffer, const Slicer &section)
 Do the actual getting of an array of values.
virtual void doPutSlice (const Array< Bool > &sourceBuffer, const IPosition &where, const IPosition &stride)
 Do the actual getting of an array of values.
virtual void setFilterZero (Bool filterZero)
 Set the switch for filtering 0.0.

Private Member Functions

 FITSMask ()
Bool filterNaN (bool *pMask, const float *pData, const uInt nelems)
 Mask out ONLY NaN's.
Bool filterZeroNaN (Bool *pMask, const Float *pData, const uInt nelems)
 Mask out NaN's and values 0.0.

Private Attributes

TiledFileAccessitsTiledFilePtr
Array< FloatitsBuffer
Float itsScale
Float itsOffset
Short itsShortMagic
Int itsLongMagic
Bool itsHasIntBlanks
Bool itsFilterZero

Detailed Description

Provides an on-the-fly mask for FITS images.

Intended use:

Public interface

Prerequisite

Etymology

This class provides a pixel mask for the FITSImage class.

Synopsis

Masked values are indicated in FITS images via magic value blanking. This class provides an on-the-fly mask. The doGetSlice function reads the data values and returns an Array<Bool> which is True (good) or False (bad - blanked)

Because FITSMask inherits from Lattice<Bool> it can be used as the private pixel mask data member for FITSImage returned by the MaskedLattice::pixelMask() functions

The FITSMask object is constructed from a TiledFileAccess object. This must be the same one that the FITSImage object constructs internally. It is shared by both FITSImage and FITSMask.

Example

Motivation

FITSImage provides native access to FITS image files and needede an efficient way to handle the pixel mask other than iterating all the way through the image first to set a mask.

Definition at line 96 of file FITSMask.h.


Constructor & Destructor Documentation

casa::FITSMask::FITSMask ( TiledFileAccess tiledFileAccess)

Constructor (for 32 bit floating point).

The pointer is not cloned, just copied.

casa::FITSMask::FITSMask ( TiledFileAccess tiledFileAccess,
Float  scale,
Float  offset,
Short  magic,
Bool  hasBlanks 
)

Constructor (for 16 bit integers).

The pointer is not cloned, just copied The scale, offset, magic blanking values must come from the FITS header ('bscale', 'bzero', 'blank')

casa::FITSMask::FITSMask ( TiledFileAccess tiledFileAccess,
Float  scale,
Float  offset,
Int  magic,
Bool  hasBlanks 
)

Constructor (for 32 bit integers).

The pointer is not cloned, just copied The scale, offset, magic blanking values must come from the FITS header ('bscale', 'bzero', 'blank')

casa::FITSMask::FITSMask ( const FITSMask other)

Copy constructor (reference semantics).

The TiledFileAccess pointer is just copied.

virtual casa::FITSMask::~FITSMask ( ) [virtual]

Destructor.

casa::FITSMask::FITSMask ( ) [private]

Member Function Documentation

virtual Lattice<Bool>* casa::FITSMask::clone ( ) const [virtual]

Make a copy of the object (reference semantics).

Implements casa::Lattice< Bool >.

virtual Bool casa::FITSMask::doGetSlice ( Array< Bool > &  buffer,
const Slicer section 
) [virtual]

Do the actual getting of an array of values.

Implements casa::Lattice< Bool >.

virtual void casa::FITSMask::doPutSlice ( const Array< Bool > &  sourceBuffer,
const IPosition where,
const IPosition stride 
) [virtual]

Do the actual getting of an array of values.

Throws an exception.

Implements casa::Lattice< Bool >.

Bool casa::FITSMask::filterNaN ( bool *  pMask,
const float *  pData,
const uInt  nelems 
) [private]

Mask out ONLY NaN's.

Bool casa::FITSMask::filterZeroNaN ( Bool pMask,
const Float pData,
const uInt  nelems 
) [private]

Mask out NaN's and values 0.0.

virtual Bool casa::FITSMask::isWritable ( ) const [virtual]

Is the FITSMask writable? Returns False.

Although it is not hard to implement writing of the mask, data values would be lost because of magic blanking.

Reimplemented from casa::LatticeBase.

FITSMask& casa::FITSMask::operator= ( const FITSMask other)

The assignment operator with reference semantics.

The TiledFileAccess pointer is just copied.

virtual void casa::FITSMask::setFilterZero ( Bool  filterZero) [virtual]

Set the switch for filtering 0.0.

IPosition casa::FITSMask::shape ( ) const [virtual]

Return the shape of the Lattice including all degenerate axes (ie.

axes with a length of one)

Implements casa::LatticeBase.


Member Data Documentation

Definition at line 161 of file FITSMask.h.

Definition at line 166 of file FITSMask.h.

Definition at line 165 of file FITSMask.h.

Definition at line 164 of file FITSMask.h.

Definition at line 162 of file FITSMask.h.

Definition at line 162 of file FITSMask.h.

Definition at line 163 of file FITSMask.h.

Definition at line 160 of file FITSMask.h.


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