casa::ImageTwoPtCorr< T > Class Template Reference [Images_module]

Compute two point correlation functions from images. More...

#include <ImageTwoPtCorr.h>

List of all members.

Public Member Functions
	ImageTwoPtCorr ()
	Default constructor.
	ImageTwoPtCorr (const ImageTwoPtCorr &other)
	Copy constructor (reference semantics).
ImageTwoPtCorr &	operator= (const ImageTwoPtCorr &other)
	Assignment (reference semantics).
	~ImageTwoPtCorr ()
	Destructor.
void	autoCorrelation (ImageInterface< T > &out, const ImageInterface< T > &in, const IPosition &axes, typename LatticeTwoPtCorr< T >::Method method, Bool progress=True) const
	Compute the desired autocorrelation function for the specified plane.
void	autoCorrelation (ImageInterface< T > &out, const ImageInterface< T > &in, typename LatticeTwoPtCorr< T >::Method method, Bool progress=True) const
Static Public Member Functions
static IPosition	setUpAxes (const IPosition &axes, const CoordinateSystem &cSys)
	Helper function to set up the axes vector.
static IPosition	setUpShape (const IPosition &inShape, const IPosition &axes)
	Helper function to provide output image shape given the input shape and the axes to find the structure function over.
Private Member Functions
void	copyMiscellaneous (ImageInterface< T > &out, const ImageInterface< T > &in) const
	Copy MiscInfo, ImageInfo, and logSInk to output.
void	setCoordinateSystem (ImageInterface< T > &out, const ImageInterface< T > &in, const IPosition &axes) const
	Overwrite the CoordinateSystem.
void	setUnit (ImageInterface< T > &out) const
	Set the brightness unit.

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Detailed Description

template<class T>
class casa::ImageTwoPtCorr< T >

Compute two point correlation functions from images.

Intended use:

Public interface

Review Status

Date Reviewed:

yyyy/mm/dd

Prerequisite

• LatticeTwoPtCorr
• ImageInterface
• TempImage

Etymology

Compute the two point correlation function of an image

Synopsis

This class allows you to compute two point correlation functions from an image over planes of the specified two axes. Presently only autocorrelations and in particualt the structure function are implemented.

The structure function is S(x,y) = < [image(i,j) - image(i+x,j+y)]**2 > where x and y are absolute integer shifts (or lags) and the ensemble average is for each lag pair, x&y.

Example

Motivation

Taking the Structure Function of an image is a basic part of image analysis

To Do

• Add more types
• Add crosscorrelation

Definition at line 83 of file ImageTwoPtCorr.h.

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Constructor & Destructor Documentation

template<class T >

casa::ImageTwoPtCorr< T >::ImageTwoPtCorr

(

)

Default constructor.

template<class T >

casa::ImageTwoPtCorr< T >::ImageTwoPtCorr

(

const ImageTwoPtCorr< T > &

other

)

Copy constructor (reference semantics).

template<class T >

casa::ImageTwoPtCorr< T >::~ImageTwoPtCorr

(

)

Destructor.

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Member Function Documentation

template<class T >

void casa::ImageTwoPtCorr< T >::autoCorrelation	(	ImageInterface< T > &	out,
		const ImageInterface< T > &	in,
		const IPosition &	axes,
		typename LatticeTwoPtCorr< T >::Method	method,
		Bool	progress = True
	)			const

Compute the desired autocorrelation function for the specified plane.

You specify which two axes to compute the structure function over. If the axes array is empty (or not an argument), then the Sky plane is selected if it exists, otherwise the first two axes are selected. The CoordinateSystem of the output image is overwritten. The miscellaneous items (ImageInfo, MiscInfo, Logger) are copied from the input image to the output.

template<class T >

void casa::ImageTwoPtCorr< T >::autoCorrelation	(	ImageInterface< T > &	out,
		const ImageInterface< T > &	in,
		typename LatticeTwoPtCorr< T >::Method	method,
		Bool	progress = True
	)			const

template<class T >

void casa::ImageTwoPtCorr< T >::copyMiscellaneous	(	ImageInterface< T > &	out,
		const ImageInterface< T > &	in
	)			const [private]

Copy MiscInfo, ImageInfo, and logSInk to output.

template<class T >

ImageTwoPtCorr& casa::ImageTwoPtCorr< T >::operator=

(

const ImageTwoPtCorr< T > &

other

)

Assignment (reference semantics).

template<class T >

void casa::ImageTwoPtCorr< T >::setCoordinateSystem	(	ImageInterface< T > &	out,
		const ImageInterface< T > &	in,
		const IPosition &	axes
	)			const [private]

Overwrite the CoordinateSystem.

template<class T >

void casa::ImageTwoPtCorr< T >::setUnit

(

ImageInterface< T > &

out

)

const [private]

Set the brightness unit.

template<class T >

static IPosition casa::ImageTwoPtCorr< T >::setUpAxes	(	const IPosition &	axes,
		const CoordinateSystem &	cSys
	)			[static]

Helper function to set up the axes vector.

If axes is of length 0, it looks for the Sky (DirectionCoordinate). If that's not there, you get the first two axes in the image.

template<class T >

static IPosition casa::ImageTwoPtCorr< T >::setUpShape	(	const IPosition &	inShape,
		const IPosition &	axes
	)			[static]

Helper function to provide output image shape given the input shape and the axes to find the structure function over.

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

• images/Images/ImageTwoPtCorr.h