Compute a fixel TDI map from a tractogram


tck2fixel [ options ]  tracks fixel_folder_in fixel_folder_out fixel_data_out
  • tracks: the input tracks.
  • fixel_folder_in: the input fixel folder. Used to define the fixels and their directions
  • fixel_folder_out: the fixel folder to which the output will be written. This can be the same as the input folder if desired
  • fixel_data_out: the name of the fixel data image.


  • -angle value the max angle threshold for assigning streamline tangents to fixels (Default: 45 degrees)

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: David Raffelt (

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

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