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RNiftyReg (version 2.0.0)

buildAffine: Build an affine matrix up from its constituent transformations

Description

This function does the opposite to decomposeAffine, building up an affine matrix from its components. It can be useful for testing, or for rescaling images.

Usage

buildAffine(translation = c(0, 0, 0), scales = c(1, 1, 1), skews = c(0, 0,
  0), angles = c(0, 0, 0), source = NULL, target = NULL,
  anchor = c("none", "origin", "centre", "center"))

Arguments

translation
Translations along each axis, in pixunits units. May also be a list, such as that produced by decomposeAffine, with elements for translation, scales
scales
Scale factors along each axis.
skews
Skews in the XY, XZ and YZ planes.
angles
Roll, pitch and yaw rotation angles, in radians.
source
The source image for the transformation (required).
target
The target image for the transformation. If NULL (the default), it will be equal to source, or a rescaled version of it if any of the scales are not 1. In the latter case the scales will be reset back to 1 to produce
anchor
The fixed point for the transformation. Setting this parameter to a value other than "none" will override the translation parameter, with the final translation set to ensure that the requested point remains in the same place afte

Value

  • A 4x4 affine matrix representing the composite transformation. Note that NiftyReg affines logically transform backwards, from target to source space, so the matrix may be the inverse of what is expected.

See Also

decomposeAffine, isAffine