void runKernelTransform(MatlabImportFilter::Pointer matlabImport,
MatlabExportFilter::Pointer matlabExport) {
// check number of input arguments (the kernel transform syntax
// accepts up to 4 arguments only. Thus, we cannot use InputIndexType_MAX)
matlabImport->CheckNumberOfArguments(4, 4);
// retrieve pointers to the inputs that we are going to need here
typedef MatlabImportFilter::MatlabInputPointer MatlabInputPointer;
MatlabInputPointer inX = matlabImport->GetRegisteredInput("X");
MatlabInputPointer inY = matlabImport->GetRegisteredInput("Y");
MatlabInputPointer inXI = matlabImport->GetRegisteredInput("XI");
// register the outputs for this function at the export filter
typedef MatlabExportFilter::MatlabOutputPointer MatlabOutputPointer;
MatlabOutputPointer outYI = matlabExport->RegisterOutput(OUT_YI, "YI");
// get size of input arguments
mwSize Mx = mxGetM(inX->pm); // number of source points
mwSize Mxi = mxGetM(inXI->pm); // number of points to be warped
mwSize ndimxi; // number of dimension of points to be warped
const mwSize *dimsxi; // dimensions vector of array of points to be warped
// create pointers to input matrices
TScalarType *x
= (TScalarType *)mxGetData(inX->pm); // source points
TScalarType *y
= (TScalarType *)mxGetData(inY->pm); // target points
TScalarType *xi
= (TScalarType *)mxGetData(inXI->pm); // points to be warped
if (x == NULL) {
mexErrMsgTxt("Cannot get a pointer to input X");
}
if (y == NULL) {
mexErrMsgTxt("Cannot get a pointer to input Y");
}
if (xi == NULL) {
mexErrMsgTxt("Cannot get a pointer to input XI");
}
// type definitions and variables to store points for the kernel transform
typedef typename TransformType::PointSetType PointSetType;
typename PointSetType::Pointer fixedPointSet = PointSetType::New();
typename PointSetType::Pointer movingPointSet = PointSetType::New();
typename PointSetType::Pointer toWarpPointSet = PointSetType::New();
typedef typename PointSetType::PointsContainer PointsContainer;
typename PointsContainer::Pointer fixedPointContainer = PointsContainer::New();
typename PointsContainer::Pointer movingPointContainer = PointsContainer::New();
typedef typename PointSetType::PointType PointType;
PointType fixedPoint;
PointType movingPoint;
PointType toWarpPoint;
PointType warpedPoint;
// duplicate the input x and y matrices to PointSet format so that
// we can pass it to the ITK function
mwSize pointId=0;
for (mwSize row=0; row < Mx; ++row) {
for (mwSize col=0; col < (mwSize)Dimension; ++col) {
fixedPoint[CAST2MWSIZE(col)] = y[Mx * col + row];
movingPoint[CAST2MWSIZE(col)] = x[Mx * col + row];
}
fixedPointContainer->InsertElement(pointId, fixedPoint);
movingPointContainer->InsertElement(pointId, movingPoint);
++pointId;
}
fixedPointSet->SetPoints(fixedPointContainer);
movingPointSet->SetPoints(movingPointContainer);
// compute the transform
typename TransformType::Pointer transform;
transform = TransformType::New();
transform->SetSourceLandmarks(movingPointSet);
transform->SetTargetLandmarks(fixedPointSet);
transform->ComputeWMatrix();
// create output vector and pointer to populate it
ndimxi = mxGetNumberOfDimensions(inXI->pm);
dimsxi = mxGetDimensions(inXI->pm);
std::vector<mwSize> size;
for (mwIndex i = 0; i < ndimxi; ++i) {
size.push_back(dimsxi[i]);
}
TScalarType *yi
= matlabExport->AllocateNDArrayInMatlab<TScalarType>(outYI, size);
// transform points
for (mwSize row=0; row < Mxi; ++row) {
for (mwSize col=0; col < (mwSize)Dimension; ++col) {
toWarpPoint[CAST2MWSIZE(col)] = xi[Mxi * col + row];
}
warpedPoint = transform->TransformPoint(toWarpPoint);
for (mwSize col=0; col < (mwSize)Dimension; ++col) {
yi[Mxi * col + row] = warpedPoint[CAST2MWSIZE(col)];
}
}
// exit function
return;
}
