Resize an image by defining the new image resolution, voxel size or a scale factor


mrresize [ options ]  input output
  • input: input image to be resized.
  • output: the output image.


Note that if the image is 4D, then only the first 3 dimensions can be resized.

Also note that if the image is down-sampled, the appropriate smoothing is automatically applied using Gaussian smoothing.


  • -size dims define the new image size for the output image. This should be specified as a comma-separated list.
  • -voxel size define the new voxel size for the output image. This can be specified either as a single value to be used for all dimensions, or as a comma-separated list of the size for each voxel dimension.
  • -scale factor scale the image resolution by the supplied factor. This can be specified either as a single value to be used for all dimensions, or as a comma-separated list of scale factors for each dimension.
  • -interp method set the interpolation method to use when resizing (choices: nearest, linear, cubic, sinc. Default: cubic).

Data type options

  • -datatype spec specify output image data type. Valid choices are: float32, float32le, float32be, float64, float64le, float64be, int64, uint64, int64le, uint64le, int64be, uint64be, int32, uint32, int32le, uint32le, int32be, uint32be, int16, uint16, int16le, uint16le, int16be, uint16be, cfloat32, cfloat32le, cfloat32be, cfloat64, cfloat64le, cfloat64be, int8, uint8, bit.

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.

This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, you can obtain one at

MRtrix3 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

For more details, see