Convert linear transformation matrices


transformconvert [ options ]  input [ input ... ] operation output
  • input: the input for the specified operation
  • operation: the operation to perform, one of:flirt_import, itk_import.flirt_import: Convert a transformation matrix produced by FSL’s flirt command into a format usable by MRtrix. You’ll need to provide as additional arguments the NIfTI images that were passed to flirt with the -in and -ref options:matrix_in in ref flirt_import outputitk_import: Convert a plain text transformation matrix file produced by ITK’s (ANTS, Slicer) affine registration into a format usable by MRtrix.
  • output: the output transformation matrix.


This command allows to convert the transformation matrix provided by FSL’s flirt command and ITK’s linear transformation format to a format usable in MRtrix.


Standard options

  • -info display information messages.
  • -quiet do not display information messages or progress status. Alternatively, this can be achieved by setting the MRTRIX_QUIET environment variable to a non-empty string.
  • -debug display debugging messages.
  • -force force overwrite of output files. Caution: Using the same file as input and output might cause unexpected behaviour.
  • -nthreads number use this number of threads in multi-threaded applications (set to 0 to disable multi-threading).
  • -help display this information page and exit.
  • -version display version information and exit.

Author: Max Pietsch (

Copyright: Copyright (c) 2008-2018 the MRtrix3 contributors.

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