Interconvert between AIPS++ Images and FITS files. More...

#include <ImageFITSConverter.h>

Static Public Member Functions
static Bool	FITSToImage (ImageInterface< Float > *&newImage, String &error, const String &imageName, const String &fitsName, uInt whichRep=0, uInt whichHDU=0, uInt memoryInMB=64, Bool allowOverwrite=False, Bool zeroBlanks=False)
	Convert a FITS file to an AIPS++ image.
static Bool	ImageToFITS (String &error, ImageInterface< Float > &image, const String &fitsName, uInt memoryInMB=64, Bool preferVelocity=True, Bool opticalVelocity=True, Int BITPIX=-32, Float minPix=1.0, Float maxPix=-1.0, Bool allowOverwrite=False, Bool degenerateLast=False, Bool verbose=True, Bool stokesLast=False, Bool preferWavelength=False, Bool airWavelength=False, const String &origin=String(), Bool history=True)
	Old version static Bool FITSToImageOld(ImageInterface<Float>*& newImage, String &error, const String &imageName, const String &fitsName, uInt whichHDU = 0, uInt memoryInMB = 64, Bool allowOverwrite=False, Bool zeroBlanks=False);.
static IPosition	copyCursorShape (String &report, const IPosition &shape, uInt imagePixelSize, uInt fitsPixelSize, uInt memoryInMB)
	Helper function - used to calculate a cursor appropriate for the desired memory use.
static CoordinateSystem	getCoordinateSystem (Int &imageType, RecordInterface &headerRec, const Vector< String > &header, LogIO &os, uInt whichRep, IPosition &shape, Bool dropStokes)
	Recover CoordinateSystem from header.
static ImageInfo	getImageInfo (RecordInterface &header)
	Old version static CoordinateSystem getCoordinateSystemOld (Int& imageType, RecordInterface& header, LogIO& os, IPosition& shape, Bool dropStokes);.
static Unit	getBrightnessUnit (RecordInterface &header, LogIO &os)
	Old version static ImageInfo getImageInfoOld (RecordInterface& header);.
static void	restoreHistory (LoggerHolder &logger, ConstFitsKeywordList &kw)
	Old version static Unit getBrightnessUnitOld (RecordInterface& header, LogIO& os);.
static Bool	extractMiscInfo (RecordInterface &miscInfo, const RecordInterface &header)
	Parse header record and set MiscInfo.
static void	readBeamsTable (ImageInfo &info, const String &filename, const DataType type)
	read the BEAMS table if present and add the restoring beams to `info`
Static Public Attributes
static const String	CASAMBM
Static Private Member Functions
static Bool	ImageToFITSOut (String &error, LogIO &os, const ImageInterface< Float > &image, FitsOutput *output, uInt memoryInMB=64, Bool preferVelocity=True, Bool opticalVelocity=True, Int BITPIX=-32, Float minPix=1.0, Float maxPix=-1.0, Bool degenerateLast=False, Bool verbose=True, Bool stokesLast=False, Bool preferWavelength=False, Bool airWavelength=False, Bool primHead=True, Bool allowAppend=False, const String &origin=String(), Bool history=True)
	Put a CASA image to an opened FITS image Parameters as in "ImageToFITS".
static Bool	QualImgToFITSOut (String &error, LogIO &os, ImageInterface< Float > &image, FitsOutput *outfile, uInt memoryInMB, Bool preferVelocity, Bool opticalVelocity, Int BITPIX, Float minPix, Float maxPix, Bool degenerateLast, Bool verbose, Bool stokesLast, Bool preferWavelength, Bool airWavelength, const String &origin, Bool history)
	Put a CASA image with quality coordinate to an opened FITS file Parameters as in "ImageToFITS".
static Bool	removeFile (String &error, const File &outFile, const String &outName, Bool allowOverwrite)
static Bool	openFitsOutput (String &error, FitsOutput *(&openFitsOutput), const String &fitsName, const Bool &allowOverwrite)
	Create an open FITS file with the name given.
static void	_writeBeamsTable (FitsOutput *const &outfile, const ImageInfo &info)

Detailed Description

Interconvert between AIPS++ Images and FITS files.

Intended use:

Public interface

Review Status

Date Reviewed:: yyyy/mm/dd

Prerequisite

PagedImage
PrimaryArray (and FITS concepts in general).

Synopsis

This class is a helper class that is used to interconvert between AIPS++ images and FITS files. This adds no functionality over the general abilities available in the underlying FITS classes, however it is a useful higher-level packaging.

There are two fundamental member functions in this class. FITSToImage which turns a FITS file into an AIPS++ image, and ImageToFITS which does the opposite.

We can read images from any HDU inside the FITS file (although this isn't well tested). Images with a quality axis (i.e. contain data and error values) are stored in the primary HDU (data) and an extension HDU (error). Other images are always written to the primary HDU.

Pixels in the FITS file which are blanked are masked out (the mask is set to False) in the output image. On conversion to FITS, masked values are blanked. The mask which is read is the current default mask.

Example

A FITS to image conversion may be accomplished as follows:

       PagedImage<Float> *image = 0;
       String fitsName = "exists.fits";
       String imageName = "new.image";
       String error;
       Bool ok = ImageFITSConverter::FITSToImage(image, error, imageName, fitsName);
       if (!image) ... error ..\.

A couple of things to note:

If ok is False, the conversion failed and error will be set.
The pointer "image" is set if the conversion succeeds. If it is zero the conversion failed and error will contain an error message.
The caller is responsible for deleting the pointer image when the conversion is successful.

Similarly, an image to FITS conversion may be accomplished as follows:

       String imageName = argv[1];
       PagedImage<Float> image = ...; // An existing image from somewhere
       String fitsName = "new.fits";
       String error;
       Bool ok = ImageFITSConverter::ImageToFITS(error, image, fitsName);

A couple of similar remarks can be made about this example:

If ok is False, the conversion failed and error will be set.

Motivation

FITS files are the fundamental transport format for images in Astronomy.

To Do

It might be useful to have functions that convert between FITS and general lattices.
Add support for PagedImage<Complex>
Convert multiple images at once?
Allow writing FITS files to an image extension in an existing FITS file.

Definition at line 143 of file ImageFITSConverter.h.

Member Function Documentation

static void casa::ImageFITSConverter::_writeBeamsTable	(	FitsOutput *const &	outfile,
		const ImageInfo &	info
	)		`[static, private]`

static IPosition casa::ImageFITSConverter::copyCursorShape	(	String &	report,
		const IPosition &	shape,
		uInt	imagePixelSize,
		uInt	fitsPixelSize,
		uInt	memoryInMB
	)		`[static]`

Helper function - used to calculate a cursor appropriate for the desired memory use.

It's not intended that application programmers call this, but you may if it's useful to you.

static Bool casa::ImageFITSConverter::extractMiscInfo	(	RecordInterface &	miscInfo,
		const RecordInterface &	header
	)		`[static]`

Parse header record and set MiscInfo.

static Bool casa::ImageFITSConverter::FITSToImage	(	ImageInterface< Float > *&	newImage,
		String &	error,
		const String &	imageName,
		const String &	fitsName,
		uInt	whichRep = `0`,
		uInt	whichHDU = `0`,
		uInt	memoryInMB = `64`,
		Bool	allowOverwrite = `False`,
		Bool	zeroBlanks = `False`
	)		`[static]`

Convert a FITS file to an AIPS++ image.

newImage will be zero if the conversion fail. If the conversion succeeds, the caller is responsible for deleting this pointer.
error will be set if the conversion fails.
If imageName is empty, a TempImage will be created, otherwise a PagedImage on disk.
fitsName must already exist (and have an image at the indicated HDU).
whichRep Zero-relative coordinate representation (Starting with wcs FITS multiple coordinate representations can be stored in a FITS file)
whichHDU Zero-relative hdu. The default is correct for a primary array, set it for an image extension. Only zero has been tested.
memoryInMB. Setting this to zero will result in row-by-row copying, otherwise it will attempt to with as large a chunk-size as possible, while fitting in the desired memory.
allowOverwrite If True, allow imageName to be overwritten if it already exists.
zeroBlanks If True, allow any blanked pixels are set to zero rather than NaN

static Unit casa::ImageFITSConverter::getBrightnessUnit	(	RecordInterface &	header,
		LogIO &	os
	)		`[static]`

Old version static ImageInfo getImageInfoOld (RecordInterface& header);.

Recover brightness unit from header. Used keywords are removed from header

static CoordinateSystem casa::ImageFITSConverter::getCoordinateSystem	(	Int &	imageType,
		RecordInterface &	headerRec,
		const Vector< String > &	header,
		LogIO &	os,
		uInt	whichRep,
		IPosition &	shape,
		Bool	dropStokes
	)		`[static]`

Recover CoordinateSystem from header.

Used keywords are removed from header and the unused one returned in a Record for ease of use. Degenerate axes may be added to shape if needed

static ImageInfo casa::ImageFITSConverter::getImageInfo ( RecordInterface & header ) [static]

Old version static CoordinateSystem getCoordinateSystemOld (Int& imageType, RecordInterface& header, LogIO& os, IPosition& shape, Bool dropStokes);.

Recover ImageInfo from header. Used keywords are removed from header

static Bool casa::ImageFITSConverter::ImageToFITS	(	String &	error,
		ImageInterface< Float > &	image,
		const String &	fitsName,
		uInt	memoryInMB = `64`,
		Bool	preferVelocity = `True`,
		Bool	opticalVelocity = `True`,
		Int	BITPIX = `-32`,
		Float	minPix = `1.0`,
		Float	maxPix = `-1.0`,
		Bool	allowOverwrite = `False`,
		Bool	degenerateLast = `False`,
		Bool	verbose = `True`,
		Bool	stokesLast = `False`,
		Bool	preferWavelength = `False`,
		Bool	airWavelength = `False`,
		const String &	origin = `String()`,
		Bool	history = `True`
	)		`[static]`

Old version static Bool FITSToImageOld(ImageInterface<Float>*& newImage, String &error, const String &imageName, const String &fitsName, uInt whichHDU = 0, uInt memoryInMB = 64, Bool allowOverwrite=False, Bool zeroBlanks=False);.

Convert an AIPS++ image to a FITS file.

return True if the conversion succeeds, False otherwise.
error will be set if the conversion fails.
image The image to convert.
fitsName If the name is "-" (the minus character), then write to stdout Always writes to the primary array.
memoryInMB. Setting this to zero will result in row-by-row copying, otherwise it will attempt to with as large a chunk-size as possible, while fitting in the desired memory.
preferVelocityWrite a velocity primary spectral axis if possible.
opticalVelocityIf writing a velocity, use the optical definition (otherwise use radio).
BITPIX, minPix, maxPix BITPIX can presently be set to -32 or 16 only. When BITPIX is 16 it will write BSCALE and BZERO into the FITS file. If minPix is greater than maxPix the minimum and maximum pixel values will be determined from the array, otherwise the supplied values will be used and pixels outside that range will be truncated to the minimum and maximum pixel values (note that this truncation does not occur for BITPIX=-32).
allowOverwrite If True, allow fitsName to be overwritten if it already exists.
degenerateLast If True, axes of length 1 will be written last to the header.
preferWavelength If True, write a wavelength primary axis.
airWavelength If True and preferWavelength is True write an air wavelength primary axis.
origin gives the origin, i.e., the name of the package. If empty, it defaults to "casacore-"getVersion().

static Bool casa::ImageFITSConverter::ImageToFITSOut	(	String &	error,
		LogIO &	os,
		const ImageInterface< Float > &	image,
		FitsOutput *	output,
		uInt	memoryInMB = `64`,
		Bool	preferVelocity = `True`,
		Bool	opticalVelocity = `True`,
		Int	BITPIX = `-32`,
		Float	minPix = `1.0`,
		Float	maxPix = `-1.0`,
		Bool	degenerateLast = `False`,
		Bool	verbose = `True`,
		Bool	stokesLast = `False`,
		Bool	preferWavelength = `False`,
		Bool	airWavelength = `False`,
		Bool	primHead = `True`,
		Bool	allowAppend = `False`,
		const String &	origin = `String()`,
		Bool	history = `True`
	)		`[static, private]`

Put a CASA image to an opened FITS image Parameters as in "ImageToFITS".

In addition:

output The FITS output to write to.
primHead Write to a primary HDU.
allowAppend Allow to append extension HDU's.

static Bool casa::ImageFITSConverter::openFitsOutput	(	String &	error,
		FitsOutput *&	openFitsOutput,
		const String &	fitsName,
		const Bool &	allowOverwrite
	)		`[static, private]`

Create an open FITS file with the name given.

static Bool casa::ImageFITSConverter::QualImgToFITSOut	(	String &	error,
		LogIO &	os,
		ImageInterface< Float > &	image,
		FitsOutput *	outfile,
		uInt	memoryInMB,
		Bool	preferVelocity,
		Bool	opticalVelocity,
		Int	BITPIX,
		Float	minPix,
		Float	maxPix,
		Bool	degenerateLast,
		Bool	verbose,
		Bool	stokesLast,
		Bool	preferWavelength,
		Bool	airWavelength,
		const String &	origin,
		Bool	history
	)		`[static, private]`

Put a CASA image with quality coordinate to an opened FITS file Parameters as in "ImageToFITS".

In addition:

output The FITS output to write to.

static void casa::ImageFITSConverter::readBeamsTable	(	ImageInfo &	info,
		const String &	filename,
		const DataType	type
	)		`[static]`

read the BEAMS table if present and add the restoring beams to info

static Bool casa::ImageFITSConverter::removeFile	(	String &	error,
		const File &	outFile,
		const String &	outName,
		Bool	allowOverwrite
	)		`[static, private]`

static void casa::ImageFITSConverter::restoreHistory	(	LoggerHolder &	logger,
		ConstFitsKeywordList &	kw
	)		`[static]`

Old version static Unit getBrightnessUnitOld (RecordInterface& header, LogIO& os);.

Recover history from FITS file keywrod list into logger

Member Data Documentation

const String casa::ImageFITSConverter::CASAMBM [static]

Definition at line 146 of file ImageFITSConverter.h.

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

casacore/images/Images/ImageFITSConverter.h

Static Public Member Functions

Static Public Attributes

Static Private Member Functions