/usr/include/ITK-4.9/itkLandmarkBasedTransformInitializer.hxx is in libinsighttoolkit4-dev 4.9.0-4ubuntu1.
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*
* Copyright Insight Software Consortium
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*=========================================================================*/
#ifndef itkLandmarkBasedTransformInitializer_hxx
#define itkLandmarkBasedTransformInitializer_hxx
#include "itkLandmarkBasedTransformInitializer.h"
#include "itkMatrix.h"
#include "itkSymmetricEigenAnalysis.h"
#include <cmath>
#include "vnl/algo/vnl_qr.h"
namespace itk
{
template< typename TTransform, typename TFixedImage, typename TMovingImage >
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::LandmarkBasedTransformInitializer():
m_ReferenceImage(ITK_NULLPTR),
m_Transform(ITK_NULLPTR),
m_FixedLandmarks(0),
m_MovingLandmarks(0),
m_LandmarkWeight(0),
m_BSplineNumberOfControlPoints(4)
{}
/** default transform initializer, if transform type isn't
* specifically handled.
*/
template< typename TTransform, typename TFixedImage, typename TMovingImage >
template <typename TTransform2>
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InternalInitializeTransform(TTransform2 *)
{
if ( dynamic_cast<BSplineTransformType *>(this->m_Transform.GetPointer()) != ITK_NULLPTR )
{
this->InternalInitializeTransform(static_cast<BSplineTransformType *>(ITK_NULLPTR));
return;
}
if ( dynamic_cast<AffineTransformType *>(this->m_Transform.GetPointer()) != ITK_NULLPTR )
{
this->InternalInitializeTransform(static_cast<AffineTransformType *>(ITK_NULLPTR));
return;
}
if ( dynamic_cast< VersorRigid3DTransformType * >( this->m_Transform.GetPointer() ) != ITK_NULLPTR )
{
this->InternalInitializeTransform(static_cast< VersorRigid3DTransformType*>(ITK_NULLPTR));
return;
}
if ( dynamic_cast< Rigid2DTransformType * >(this->m_Transform.GetPointer() ) != ITK_NULLPTR )
{
this->InternalInitializeTransform(static_cast<Rigid2DTransformType *>(ITK_NULLPTR));
return;
}
itkExceptionMacro( <<"Unsupported Transform Type " << this->m_Transform->GetNameOfClass() );
}
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InternalInitializeTransform(BSplineTransformType *)
{
BSplineTransformType *transform =
dynamic_cast<BSplineTransformType *>(this->m_Transform.GetPointer());
if ( transform == ITK_NULLPTR )
{
itkExceptionMacro( << "BSplineTransform Expected but transform is "
<< this->m_Transform->GetNameOfClass() );
}
if( m_ReferenceImage.IsNull() )
{
itkExceptionMacro( << "Reference image required for BSplineTransform initialization is NULL (not set or set to NULL)." );
}
const unsigned int numberOfLandMarks = m_MovingLandmarks.size();
// Instantiating B-spline filter and creating B-spline domain
//
typedef Vector< double, ImageDimension > VectorType;
typedef Image< VectorType, ImageDimension > VectorImageType;
typedef PointSet< typename VectorImageType::PixelType, ImageDimension > PointSetType;
typedef BSplineScatteredDataPointSetToImageFilter<PointSetType, VectorImageType> FilterType;
typedef typename FilterType::WeightsContainerType WeightsContainerType;
typename WeightsContainerType::Pointer weights = WeightsContainerType::New();
weights->Reserve( numberOfLandMarks );
if( !m_LandmarkWeight.empty() )
{
if( m_LandmarkWeight.size() != numberOfLandMarks)
{
itkExceptionMacro( << "Size mismatch between number of landmarks pairs and weights" );
}
LandmarkWeightConstIterator weightIt = m_LandmarkWeight.begin();
for( size_t i = 0; weightIt != m_LandmarkWeight.end(); ++i, ++weightIt )
{
weights->InsertElement(i, (*weightIt) );
}
}
else
{
// Set weights to identity
for( size_t i = 0; i < numberOfLandMarks; ++i )
{
weights->InsertElement(i, 1);
}
}
// Set a pointSet from the input landmarks
typename PointSetType::Pointer pointSet = PointSetType::New();
pointSet->Initialize();
PointsContainerConstIterator fixedIt = m_FixedLandmarks.begin();
PointsContainerConstIterator movingIt = m_MovingLandmarks.begin();
for(size_t i = 0; fixedIt != m_FixedLandmarks.end(); ++i, ++fixedIt, ++movingIt )
{
pointSet->SetPoint( i, (*fixedIt) );
VectorType vectorTmp;
for( unsigned int d=0; d<ImageDimension; ++d )
{
vectorTmp[d] = (*movingIt)[d] - (*fixedIt)[d];
}
pointSet->SetPointData( i, vectorTmp );
}
const typename VectorImageType::SizeType size = this->m_ReferenceImage->GetLargestPossibleRegion().GetSize();
const typename VectorImageType::PointType origin = this->m_ReferenceImage->GetOrigin();
const typename VectorImageType::SpacingType spacing = this->m_ReferenceImage->GetSpacing();
const typename VectorImageType::DirectionType direction = this->m_ReferenceImage->GetDirection();
typename FilterType::Pointer filter = FilterType::New();
// Define the parametric domain.
filter->SetOrigin( origin );
filter->SetSpacing( spacing );
filter->SetSize( size );
filter->SetDirection( direction );
filter->SetInput( pointSet );
filter->SetPointWeights( weights );
filter->SetGenerateOutputImage( false );
filter->SetSplineOrder( SplineOrder );
typename FilterType::ArrayType ncps;
ncps.Fill( this->m_BSplineNumberOfControlPoints ); // should be greater than SplineOrder
filter->SetNumberOfControlPoints( ncps );
filter->SetNumberOfLevels( 3 );
typename FilterType::ArrayType close;
close.Fill( 0 );
filter->SetCloseDimension( close );
filter->Update();
//Set the BSpline transform
//
typedef typename BSplineTransformType::ImageType CoefficientImageType;
typename BSplineTransformType::CoefficientImageArray coefficientImages;
for( unsigned int j = 0; j < ImageDimension; ++j )
{
typedef VectorIndexSelectionCastImageFilter<VectorImageType, CoefficientImageType> SelectorType;
typename SelectorType::Pointer selector = SelectorType::New();
selector->SetInput( filter->GetPhiLattice() );
selector->SetIndex( j );
coefficientImages[j] = selector->GetOutput();
coefficientImages[j]->Update();
coefficientImages[j]->DisconnectPipeline();
}
transform->SetCoefficientImages( coefficientImages );
}
/** Compute an affine transform from landmark set.
* This was implemented by Eun Young Kim based on method
* described in the paper "Closed-form solution of absolute
* orientation using orthonormal matrices" by Horn, Hilden, and
* Negahdaripour. See http://www.opticsinfobase.org/abstract.cfm?&id=3143
*/
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InternalInitializeTransform(AffineTransformType *)
{
AffineTransformType *transform =
dynamic_cast<AffineTransformType *>(this->m_Transform.GetPointer());
if ( transform == ITK_NULLPTR )
{
itkExceptionMacro( << "AffineTransform Expected but transform is "
<< this->m_Transform->GetNameOfClass() );
}
const unsigned int numberOfLandmarks = m_MovingLandmarks.size();
if( numberOfLandmarks < LandmarkPointContainer::value_type::GetPointDimension()+1 )
{
itkExceptionMacro( << " insufficient number of landmarks, expected "
<< LandmarkPointContainer::value_type::GetPointDimension()+1
<< " got "<< numberOfLandmarks );
}
//[Set Landmark Weight]
//:: If no landmark weights are given, weight matrix is identity matrix
vnl_matrix<ParametersValueType> vnlWeight( numberOfLandmarks,numberOfLandmarks,0);
vnlWeight.set_identity();
if( !m_LandmarkWeight.empty() )
{
if( m_LandmarkWeight.size() != numberOfLandmarks)
{
itkExceptionMacro( << " size mismatch between number of landmars pairs and weights" );
}
LandmarkWeightConstIterator weightIt = m_LandmarkWeight.begin();
for( size_t i = 0; weightIt != m_LandmarkWeight.end(); ++i, ++weightIt )
{
vnlWeight(i,i)=(*weightIt);
}
}
// Normalize weights
//
vnlWeight=vnlWeight/vnlWeight.fro_norm();
//[Convert Point to Matrix for Matrix Muptiplication]
//
// q
// dim+1=4 * numberOfLandmarks matrix
vnl_matrix< ParametersValueType > q( ImageDimension+1, numberOfLandmarks, 0.0F);
PointsContainerConstIterator fixedIt = m_FixedLandmarks.begin();
for( size_t i = 0; fixedIt != m_FixedLandmarks.end(); ++i, ++fixedIt )
{
for(unsigned int dim =0; dim< ImageDimension; dim++ )
{
q( dim,i ) = (*fixedIt)[dim];
}
q(ImageDimension,i)=1.0F;
}
q *= vnlWeight;
// p
// dim=3 * numberOfLandmarks matrix
vnl_matrix< ParametersValueType > p( ImageDimension, numberOfLandmarks,0.0F);
PointsContainerConstIterator movingIt = m_MovingLandmarks.begin();
for( size_t i = 0; movingIt != m_MovingLandmarks.end(); ++i, ++movingIt )
{
for( unsigned int dim =0; dim< ImageDimension; dim++ )
{
p( dim,i ) = (*movingIt)[dim];
}
}
p *= vnlWeight;
// EX) 3 dimensional case
// | sum( q(1,i)*q(1,i) sum( q(1,i)*q(2,i) sum( q(1,i)*q(3,i) sum( q(1,i) ) |
// Q[4x4] = | sum( q(2,i)*q(1,i) sum( q(2,i)*q(2,i) sum( q(2,i)*q(3,i) sum( q(2,i) ) |
// | sum( q(3,i)*q(1,i) sum( q(3,i)*q(2,i) sum( q(3,i)*q(3,i) sum( q(3,i) ) |
// | sum( q(1,i) ) sum( q(2,i) ) sum( q(3,i) ) sum( q(4,i) ) |
//
// | a(1,1) a(2,1) a(3,1) |
// a[4x3] = | a(1,2) a(2,2) a(3,2) |
// | a(1,3) a(2,3) a(3,3) |
// | a(1,4) a(2,4) a(3,4) |
//
// | sum( q(1,i)*p(1,i) ) sum( q(1,i)*p(2,i) ) sum( q(1,i)*p(3,i) ) |
// C[4x3] = | sum( q(2,i)*p(1,i) ) sum( q(2,i)*p(2,i) ) sum( q(2,i)*p(3,i) ) |
// | sum( q(3,i)*p(1,i) ) sum( q(3,i)*p(2,i) ) sum( q(3,i)*p(3,i) ) |
// | sum( p(1,i) ) sum( p(2,i) ) sum( p(3,i) ) |
//
// [Q]
//
vnl_matrix<ParametersValueType> Q( ImageDimension+1,ImageDimension+1, 0.0F );
for( size_t i =0; i<numberOfLandmarks; i++)
{ // Iterate for the number of landmakrs
vnl_matrix< ParametersValueType > qTemp( ImageDimension+1, 1 );
// convert vector to colume matrix
for( unsigned int k=0; k<ImageDimension+1;k++ )
{
qTemp(k,0)=q.get(k,i);
}
vnl_matrix< ParametersValueType > qTempT( 1, ImageDimension+1 );
qTempT= qTemp.transpose();
Q = Q + qTemp*qTempT;
}
// [C]
//
vnl_matrix<ParametersValueType> C( ImageDimension+1,ImageDimension, 0 );
for( size_t i =0; i<numberOfLandmarks; i++ )
{
vnl_matrix< ParametersValueType > qTemp( ImageDimension+1, 1 );
vnl_matrix< ParametersValueType > pTemp( 1, ImageDimension );
// convert vector to colume matrix
for( unsigned int k=0; k<ImageDimension+1;k++ )
{
qTemp(k,0)=q.get(k,i);
}
for( unsigned int k=0; k<ImageDimension;k++ )
{
pTemp(0,k)=p.get(k,i);
}
C = C + qTemp*pTemp;
}
// [Solve Qa=C]
// :: Solving code is from
// http://www.itk.org/pipermail/insight-users/2008-December/028207.html
vnl_matrix<ParametersValueType> transposeAffine =
vnl_qr<ParametersValueType> ( Q ).solve( C );
vnl_matrix<ParametersValueType> Affine= transposeAffine.transpose();
vnl_matrix<ParametersValueType> AffineRotation =
vnl_matrix<ParametersValueType>(Affine.get_n_columns(0,ImageDimension));
// [Convert ITK Affine Transformation from vnl]
//
// Define Matrix Type
//
itk::Matrix<ParametersValueType,ImageDimension,ImageDimension> mA =
itk::Matrix<ParametersValueType,ImageDimension,ImageDimension>(AffineRotation);
itk::Vector<ParametersValueType,ImageDimension> mT;
for( unsigned int t=0;t<ImageDimension;t++ )
{
mT[t] = Affine(t,ImageDimension);
}
transform->SetMatrix( mA );
transform->SetOffset( mT );
}
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InternalInitializeTransform(VersorRigid3DTransformType *)
{
itkDebugMacro("Internal Initialize VersorRigid3DTransformType");
VersorRigid3DTransformType *transform = dynamic_cast< VersorRigid3DTransformType * >(
this->m_Transform.GetPointer() );
if ( transform == ITK_NULLPTR )
{
itkExceptionMacro( << "VersorRigid3DTransformType Expected but transform is "
<< this->m_Transform->GetNameOfClass() );
}
// Sanity check
if ( ImageDimension != 3 )
{
itkExceptionMacro(
"Transform is VersorRigid3DTransform and Fixed image dimension is not 3");
return;
}
if ( MovingImageType::ImageDimension != 3 )
{
itkExceptionMacro(
"Transform is VersorRigid3DTransform and Moving image dimension is not 3");
return;
}
// --- compute the necessary transform to match the two sets of landmarks
// ---
//
//
// The solution is based on
// Berthold K. P. Horn (1987),
// "Closed-form solution of absolute orientation using unit
// quaternions,"
// Journal of the Optical Society of America A, 4:629-642
//
//
// Original python implementation by David G. Gobbi
// Readpted from the code in VTK: Hybrid/vtkLandmarkTransform
//
//----------------------------------------------------------------------------
typedef typename VersorRigid3DTransformType::OutputVectorType VectorType;
typedef typename VersorRigid3DTransformType::OutputPointType PointType;
// Compute the centroids
PointType fixedCentroid;
fixedCentroid.Fill(0.0);
PointsContainerConstIterator fixedItr = m_FixedLandmarks.begin();
while ( fixedItr != m_FixedLandmarks.end() )
{
fixedCentroid[0] += ( *fixedItr )[0];
fixedCentroid[1] += ( *fixedItr )[1];
fixedCentroid[2] += ( *fixedItr )[2];
++fixedItr;
}
fixedCentroid[0] /= m_FixedLandmarks.size();
fixedCentroid[1] /= m_FixedLandmarks.size();
fixedCentroid[2] /= m_FixedLandmarks.size();
PointsContainerConstIterator movingItr = m_MovingLandmarks.begin();
PointType movingCentroid;
movingCentroid.Fill(0.0);
while ( movingItr != m_MovingLandmarks.end() )
{
movingCentroid[0] += ( *movingItr )[0];
movingCentroid[1] += ( *movingItr )[1];
movingCentroid[2] += ( *movingItr )[2];
++movingItr;
}
movingCentroid[0] /= m_MovingLandmarks.size();
movingCentroid[1] /= m_MovingLandmarks.size();
movingCentroid[2] /= m_MovingLandmarks.size();
itkDebugMacro(<< "fixed centroid = " << fixedCentroid);
itkDebugMacro(<< "moving centroid = " << movingCentroid);
typedef typename VersorRigid3DTransformType::VersorType VersorType;
VersorType versor;
// If we have at least 3 landmarks, we can compute a rotation.
// Otherwise the versor will be an identity versor.
if ( m_FixedLandmarks.size() >= ImageDimension )
{
itk::Matrix< ParametersValueType, ImageDimension, ImageDimension > M;
fixedItr = m_FixedLandmarks.begin();
movingItr = m_MovingLandmarks.begin();
VectorType fixedCentered;
VectorType movingCentered;
fixedCentered.Fill(0.0);
movingCentered.Fill(0.0);
itkDebugStatement(int ii = 0; )
// Computations are relative to the Center of Rotation.
while ( movingItr != m_MovingLandmarks.end() )
{
for ( unsigned int i = 0; i < ImageDimension; i++ )
{
fixedCentered[i] = ( *fixedItr )[i] - fixedCentroid[i];
movingCentered[i] = ( *movingItr )[i] - movingCentroid[i];
}
for ( unsigned int i = 0; i < ImageDimension; i++ )
{
for ( unsigned int j = 0; j < ImageDimension; j++ )
{
// mmm this indices i,j may have to be reverted...
M[i][j] += fixedCentered[i] * movingCentered[j];
}
}
itkDebugStatement(++ii; )
itkDebugMacro(<< "f_" << ii << " = " << fixedCentered);
itkDebugMacro(<< "m_" << ii << " = " << movingCentered);
++movingItr;
++fixedItr;
}
// -- build the 4x4 matrix N --
itk::Matrix< ParametersValueType, 4, 4 > N;
// on-diagonal elements
N[0][0] = M[0][0] + M[1][1] + M[2][2];
N[1][1] = M[0][0] - M[1][1] - M[2][2];
N[2][2] = -M[0][0] + M[1][1] - M[2][2];
N[3][3] = -M[0][0] - M[1][1] + M[2][2];
// off-diagonal elements
N[0][1] = N[1][0] = M[1][2] - M[2][1];
N[0][2] = N[2][0] = M[2][0] - M[0][2];
N[0][3] = N[3][0] = M[0][1] - M[1][0];
N[1][2] = N[2][1] = M[0][1] + M[1][0];
N[1][3] = N[3][1] = M[2][0] + M[0][2];
N[2][3] = N[3][2] = M[1][2] + M[2][1];
itkDebugMacro(<< "For Closed form solution: ");
itkDebugMacro(<< "M matrix " << M);
itkDebugMacro(<< "N matrix " << N);
vnl_matrix< ParametersValueType > eigenVectors(4, 4);
vnl_vector< ParametersValueType > eigenValues(4);
typedef itk::SymmetricEigenAnalysis<
itk::Matrix< ParametersValueType, 4, 4 >,
vnl_vector< ParametersValueType >,
vnl_matrix< ParametersValueType > > SymmetricEigenAnalysisType;
SymmetricEigenAnalysisType symmetricEigenSystem(4);
symmetricEigenSystem.ComputeEigenValuesAndVectors(N, eigenValues, eigenVectors);
itkDebugMacro(<< "EigenVectors " << eigenVectors);
itkDebugMacro(<< "EigenValues " << eigenValues);
// By default eigen values are sorted in ascending order. therefore the
// maximum
// eigen value is the one in the fourth place = index 3. We need the
// eigen
// vector associated with the maximum eigenvalue, so we take the
// eigenvector
// from the last row, index=3.
versor.Set(eigenVectors[3][1],
eigenVectors[3][2],
eigenVectors[3][3],
eigenVectors[3][0]);
itkDebugMacro(<< "Resulting versor" << versor);
}
else
{
// Remember..
// Less than 3 landmarks available. Rotation is not computed
}
transform->SetCenter(fixedCentroid);
transform->SetRotation(versor);
VectorType translation = transform->GetTranslation();
translation = movingCentroid - fixedCentroid;
transform->SetTranslation(translation);
}
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InternalInitializeTransform(Rigid2DTransformType *)
{
itkDebugMacro("Internal Initialize VersorRigid3DTransformType");
Rigid2DTransformType *transform =
dynamic_cast< Rigid2DTransformType * >(this->m_Transform.GetPointer() );
if ( transform == ITK_NULLPTR )
{
itkExceptionMacro( << "VersorRigid3DTransformType Expected but transform is "
<< this->m_Transform->GetNameOfClass() );
}
// Sanity check
if ( ImageDimension != 2 )
{
itkExceptionMacro(
"Transform is Rigid2DTransfrom and Fixed image dimension is not 2");
return;
}
if ( MovingImageType::ImageDimension != 2 )
{
itkExceptionMacro(
"Transform is Rigid2DTransform and Moving image dimension is not 2");
return;
}
const double PI = 4.0 * std::atan(1.0);
typedef typename Rigid2DTransformType::OutputVectorType VectorType;
typedef typename Rigid2DTransformType::OutputPointType PointType;
//Initialize the transform to identity
transform->SetIdentity();
// Compute the centroids
PointType fixedCentroid;
fixedCentroid.Fill(0.0);
PointsContainerConstIterator fixedItr = m_FixedLandmarks.begin();
while ( fixedItr != m_FixedLandmarks.end() )
{
fixedCentroid[0] += ( *fixedItr )[0];
fixedCentroid[1] += ( *fixedItr )[1];
++fixedItr;
}
fixedCentroid[0] /= m_FixedLandmarks.size();
fixedCentroid[1] /= m_FixedLandmarks.size();
PointsContainerConstIterator movingItr = m_MovingLandmarks.begin();
PointType movingCentroid;
movingCentroid.Fill(0.0);
while ( movingItr != m_MovingLandmarks.end() )
{
movingCentroid[0] += ( *movingItr )[0];
movingCentroid[1] += ( *movingItr )[1];
++movingItr;
}
movingCentroid[0] /= m_MovingLandmarks.size();
movingCentroid[1] /= m_MovingLandmarks.size();
itkDebugMacro(<< "fixed centroid = " << fixedCentroid);
itkDebugMacro(<< "moving centroid = " << movingCentroid);
double rotationAngle = 0.0;
// If we have at least 2 landmarks, we can compute a rotation.
// Otherwise the rotation matrix will be identity.
//
// For the Rigid2DTransform, the least squares error will be minimized
// by choosing the offset as the distance between the two centroids,
// fixed centroid (after having undergone the rotation transform, that
// we must compute) and the moving centroid.
// The rotation angle will be given by the cross and dot products of the
// fixed and moving landmark vectors, the vectors being computed relative
// to the fixed and moving centroids.
if ( m_FixedLandmarks.size() >= 2 )
{
fixedItr = m_FixedLandmarks.begin();
movingItr = m_MovingLandmarks.begin();
VectorType fixedCentered;
VectorType movingCentered;
fixedCentered.Fill(0.0);
movingCentered.Fill(0.0);
itkDebugStatement(int ii = 0; )
double s_dot = 0;
double s_cross = 0;
// Computations are relative to the Center of Rotation.
while ( movingItr != m_MovingLandmarks.end() )
{
fixedCentered[0] = ( *fixedItr )[0] - fixedCentroid[0];
movingCentered[0] = ( *movingItr )[0] - movingCentroid[0];
fixedCentered[1] = ( *fixedItr )[1] - fixedCentroid[1];
movingCentered[1] = ( *movingItr )[1] - movingCentroid[1];
s_dot += ( movingCentered[0] * fixedCentered[0] )
+ ( movingCentered[1] * fixedCentered[1] );
s_cross += ( movingCentered[1] * fixedCentered[0] )
- ( movingCentered[0] * fixedCentered[1] );
itkDebugStatement(++ii; )
itkDebugMacro(<< "f_" << ii << " = " << fixedCentered);
itkDebugMacro(<< "m_" << ii << " = " << movingCentered);
++movingItr;
++fixedItr;
}
itkDebugMacro(<< "Dot Product of landmarks: " << s_dot << " Cross Product: " << s_cross);
if ( std::fabs(s_dot) > 0.00005 )
{
rotationAngle = std::atan2(s_cross, s_dot);
}
else
{
rotationAngle = -0.5 * PI;
}
}
else
{
itkWarningMacro(<< "Less than 2 landmarks available. Rotation is not computed");
}
typename Rigid2DTransformType::Pointer t = Rigid2DTransformType::New();
t->SetIdentity();
t->SetAngle(rotationAngle);
transform->SetCenter(fixedCentroid);
transform->SetAngle(rotationAngle);
VectorType translation = transform->GetTranslation();
itkDebugMacro(<< "Initial transform translation: " << translation);
translation = movingCentroid - fixedCentroid;
itkDebugMacro(<< "translation computed as difference of centroids: " << translation);
transform->SetTranslation(translation);
}
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::InitializeTransform()
{
// Sanity check
if ( !m_Transform )
{
itkExceptionMacro("Transform has not been set");
return;
}
if ( m_FixedLandmarks.size() != m_MovingLandmarks.size() )
{
itkExceptionMacro("Different number of fixed and moving landmarks");
return;
}
this->InternalInitializeTransform(static_cast<TTransform *>(ITK_NULLPTR));
}
template< typename TTransform, typename TFixedImage, typename TMovingImage >
void
LandmarkBasedTransformInitializer< TTransform, TFixedImage, TMovingImage >
::PrintSelf(std::ostream & os, Indent indent) const
{
Superclass::PrintSelf(os, indent);
itkPrintSelfObjectMacro( Transform );
itkPrintSelfObjectMacro( ReferenceImage );
os << indent << "Fixed Landmarks: " << std::endl;
PointsContainerConstIterator fitr = m_FixedLandmarks.begin();
while ( fitr != m_FixedLandmarks.end() )
{
os << indent << *fitr << std::endl;
++fitr;
}
os << indent << "Moving Landmarks: " << std::endl;
PointsContainerConstIterator mitr = m_MovingLandmarks.begin();
while ( mitr != m_MovingLandmarks.end() )
{
os << indent << *mitr << std::endl;
++mitr;
}
os << indent << "Landmark Weight: " << std::endl;
LandmarkWeightConstIterator witr = m_LandmarkWeight.begin();
while ( witr != m_LandmarkWeight.end() )
{
os << indent << *witr << std::endl;
++witr;
}
os << indent << "BSplineNumberOfControlPoints: " << m_BSplineNumberOfControlPoints << std::endl;
}
} // namespace itk
#endif /* itkLandmarkBasedTransformInitializer_hxx */
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