fitThinPlateSplineDisplacementField: fitThinPlateSplineDisplacementField

In neuroconductor-devel/ANTsR: ANTs in R: Quantification Tools for Biomedical Images

fitThinPlateSplineDisplacementField

Description

Fit a thin-plate spline object to a set of source points with associated displacements. This is basically a wrapper for the ITK class https://itk.org/Doxygen/html/itkThinPlateSplineKernelTransform_8h.html. Returns a displacement field.

Usage

fitThinPlateSplineDisplacementField(
  displacementOrigins = NULL,
  displacements = NULL,
  origin = NULL,
  spacing = NULL,
  size = NULL,
  direction = NULL
)

Arguments

displacementOrigins	matrix (numberOfPoints x dimension) defining the origins of the input displacement points. Default = NULL.
displacements	matrix (numberOfPoints x dimension) defining the displacements of the input displacement points. Default = NULL.
origin	vector defining the physical origin of the B-spline displacement field. Must be specified if displacementField is not specified. Otherwise, the displacementField is used to define the domain parameters.
spacing	vector defining the physical spacing of the B-spline object. Defines the sampling rate in the parametric domain. Must be specified if displacementField is not specified. Otherwise, the displacementField is used to define the domain parameters.
size	vector defining the size (length) of the B-spline object. Note that the length of the B-spline object in dimension d is defined as parametricDomainSpacing[d] * (parametricDomainSize[d]-1). Must be specified if displacementField is not specified. Otherwise, the displacementField is used to define the domain parameters.
direction	matrix defining the orientation of the sampled B-spline object. Must be specified if displacementField is not specified. Otherwise, the displacementField is used to define the domain parameters.

Value

ANTsR image.

Author(s)

NJ Tustison

Examples

# Perform 2-D fitting

points <- matrix(data = c(-50, -50), nrow = 1, byrow = TRUE)
deltas <- matrix(data = c(10, 10), nrow = 1, byrow = TRUE)

tpsField <- fitThinPlateSplineDisplacementField(
  displacementOrigins = points, displacements = deltas,
  origin = c(0.0, 0.0), spacing = c(1.0, 1.0), size = c(100, 100),
  direction = matrix(data = c(-1, 0, 0, -1), nrow = 2, byrow = TRUE)
)

neuroconductor-devel/ANTsR documentation built on July 3, 2025, 10:41 p.m.