svkMultiCoilPhase Class Reference

#include <svkMultiCoilPhase.h>

Inheritance diagram for svkMultiCoilPhase:

Public Member Functions
	vtkTypeMacro (svkMultiCoilPhase, svkImageInPlaceFilter)
float	PhaseBySymmetry (vtkFloatArray *spectrum, int peakMaxPtIn, int peakStartPtIn, int peakStopPtIn)
float	CalculateCenterPhase (int timePt, int coilNum)
Public Member Functions inherited from svkImageInPlaceFilter
	vtkTypeMacro (svkImageInPlaceFilter, vtkImageInPlaceFilter)
svkImageData *	GetOutput ()
svkImageData *	GetOutput (int port)
svkImageData *	GetImageDataInput (int port)

Static Public Member Functions
static svkMultiCoilPhase *	New ()

Protected Member Functions
	svkMultiCoilPhase ()
	~svkMultiCoilPhase ()
virtual int	FillInputPortInformation (int port, vtkInformation *info)
virtual int	RequestInformation (vtkInformation *request, vtkInformationVector **inputVector, vtkInformationVector *outputVector)
virtual int	RequestData (vtkInformation *request, vtkInformationVector **inputVector, vtkInformationVector *outputVector)
Protected Member Functions inherited from svkImageInPlaceFilter
	svkImageInPlaceFilter ()
	~svkImageInPlaceFilter ()
virtual int	FillOutputPortInformation (int vtkNotUsed(port), vtkInformation *info)
virtual int	FillInputPortInformation (int vtkNotUsed(port), vtkInformation *info)

Detailed Description

Class to apply a per channel phase factor to spectra prior to combining multi-coil data to achieve constructive addition of data from individual coils. References and Acknowledgments: Sarah J. Nelson, ISMRM abstract (Wei et al) k.Hammond.

Constructor & Destructor Documentation

svkMultiCoilPhase ( )

protected

References svkPhaseSpec::New().

~svkMultiCoilPhase ( )

protected

Member Function Documentation

float CalculateCenterPhase	(	int	timePt,
		int	coilNum
	)

Finds the average phase of the center 8 voxels (or 1 voxel for single voxel data).

References svkImageData::GetDcmHeader(), svkImageInPlaceFilter::GetImageDataInput(), svkMrsImageData::GetNumberOfChannels(), svkDcmHeader::GetNumberOfTimePoints(), svk4DImageData::GetNumberOfVoxels(), and svkMultiCoilPhase::PhaseBySymmetry().

Referenced by svkMultiCoilPhase::RequestData().

int FillInputPortInformation ( int  port, vtkInformation *  info  )

protectedvirtual

static svkMultiCoilPhase* New ( )

static

float PhaseBySymmetry	(	vtkFloatArray *	spectrum,
		int	peakMaxPtIn,
		int	peakStartPtIn,
		int	peakStopPtIn
	)

Returns the phase of the peak at the specified position determined by maximizing the real component symmetry: left and right side should have equivalent positive integrals.

References svkImageInPlaceFilter::GetImageDataInput(), svkSpecUtils::GetMagnigutude(), and svkSpecUtils::PhaseSpectrum().

Referenced by svkMultiCoilPhase::CalculateCenterPhase(), and svkMultiCoilPhase::RequestData().

int RequestData ( vtkInformation *  request, vtkInformationVector **  inputVector, vtkInformationVector *  outputVector  )

protectedvirtual

Algorithm needs to

1. a)either find the optimal phase from the central voxels in the volume from each coil and average it or b) average the central voxels.. no, destructive interference prevents addition prior to phasing!.. do a)
2. to find the phase we first need to find the peak: Phase using the water peak (predefined ppm range)
3. method for phasing = TBD, see Sarah Code.
4. use phasing algorithm already implemented to apply the phases to the specified coil (bundle the vtkPhaseSpec call inside this class.

for each of central voxels: Find peak from mag spec and calc its phase: use smoothed magnitude spectrum to find maximum point (sub est_peakmagmax) get phase angle at max pos: a0 = 180.0 * atan2(aimag(r(imax)),real(r(imax)))/3.14159 now estimate the peak sym: call est_peaksym(ncol,r,rback,s1pos,s2pos,imax,a1,nsmooth) -> see csi_subs_v6.f

References svkMultiCoilPhase::CalculateCenterPhase(), svkImageData::GetDcmHeader(), svkImageInPlaceFilter::GetImageDataInput(), svkDcmHeader::GetNumberOfCoils(), svkDcmHeader::GetNumberOfTimePoints(), svkImageData::GetNumberOfVoxels(), svkImageInPlaceFilter::GetOutput(), svkPhaseSpec::New(), svkMultiCoilPhase::PhaseBySymmetry(), svkPhaseSpec::SetChannel(), svkPhaseSpec::SetPhase0(), and svkPhaseSpec::SetUpdateExtent().

int RequestInformation ( vtkInformation *  request, vtkInformationVector **  inputVector, vtkInformationVector *  outputVector  )

protectedvirtual

vtkTypeMacro	(	svkMultiCoilPhase	,
		svkImageInPlaceFilter
	)

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

• svkMultiCoilPhase.h
• svkMultiCoilPhase.cc