NIFTI1_TOOL,(1)

✨ NAME ✨

okay so bestie, meet nifti1_tool 💖 — this is the manual page for nifti1_tool, version 1.24, dated September 26, 2012. yes it's giving vintage, but it still eats 💅

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💅 DESCRIPTION 💅

okay so nifti_tool is that girl. here's what she does:

• display, modify or compare nifti structures in datasets
• copy a dataset by selecting a list of volumes from the original
• copy a dataset, collapsing any dimensions, each to a single index
• display a time series for a voxel, or more generally, the data from any collapsed image, in ASCII text

ngl this program is so versatile. she can:

• display information from nifti datasets
• modify information in nifti datasets
• look for differences between two nifti datasets (like the UNIX 'diff' command, fr fr)
• copy a dataset to a new one, either by restricting any dimensions, or by copying a list of volumes (the time dimension) from a dataset

🚨 only one action type is allowed at a time, bestie. like, you literally cannot modify a dataset and then take a 'diff'. pick a lane, one action, periodt.

so here's the full menu of what she can do 👑

• one can display
  • any or all fields in the nifti_1_header structure
  • any or all fields in the nifti_image structure
  • any or all fields in the nifti_analyze75 structure
  • the extensions in the nifti_image structure
  • the time series from a 4-D dataset, given i,j,k
  • the data from any collapsed image, given dims. list
• one can check
  • perform internal check on the nifti_1_header struct (by nifti_hdr_looks_good())
  • perform internal check on the nifti_image struct (by nifti_nim_is_valid())
• one can modify
  • any or all fields in the nifti_1_header structure
  • any or all fields in the nifti_image structure
  • swap all fields in NIFTI or ANALYZE header structure
• add/rm — any or all extensions in the nifti_image structure
• remove — all extensions and descriptions from the datasets
• one can compare
  • any or all field pairs of nifti_1_header structures
  • any or all field pairs of nifti_image structures
• one can copy
  • an arbitrary list of dataset volumes (time points)
  • a dataset, collapsing across arbitrary dimensions (restricting those dimensions to the given indices)
• one can create
  • a new dataset out of nothing

💡 note, bestie: to learn about which fields exist in either of the structures, or to learn a field's type, size of each element, or the number of elements in the field, use either the -help_hdr option or the -help_nim option. no further options are required. iykyk 🧚

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🎀 usage styles 🎀

okay these are the little one-liners, the vibe check of every mode:

• nifti_tool -help — show this help
• nifti_tool -help_hdr — show nifti_1_header field info
• nifti_tool -help_nim — show nifti_image field info
• nifti_tool -help_ana — show nifti_analyze75 field info
• nifti_tool -help_datatypes — show datatype table
• nifti_tool -ver — show the current version
• nifti_tool -hist — show the modification history
• nifti_tool -nifti_ver — show the nifti library version
• nifti_tool -nifti_hist — show the nifti library history
• nifti_tool -with_zlib — was library compiled with zlib

and now the big girls, the full shapes of every invocation 🦋

nifti_tool -check_hdr -infiles f1 ...
nifti_tool -check_nim -infiles f1 ...
nifti_tool -copy_brick_list -infiles f1'[indices...]'
nifti_tool -copy_collapsed_image I J K T U V W -infiles f1
nifti_tool -copy_im -infiles f1
nifti_tool -make_im -prefix new_im.nii
nifti_tool -disp_hdr [-field FIELDNAME] [...] -infiles f1 ...
nifti_tool -disp_nim [-field FIELDNAME] [...] -infiles f1 ...
nifti_tool -disp_ana [-field FIELDNAME] [...] -infiles f1 ...
nifti_tool -disp_exts -infiles f1 ...
nifti_tool -disp_ts I J K [-dci_lines] -infiles f1 ...
nifti_tool -disp_ci I J K T U V W [-dci_lines] -infiles f1 ...
nifti_tool -mod_hdr [-mod_field FIELDNAME NEW_VAL] [...] -infiles f1
nifti_tool -mod_nim [-mod_field FIELDNAME NEW_VAL] [...] -infiles f1
nifti_tool -swap_as_nifti -overwrite -infiles f1
nifti_tool -swap_as_analyze -overwrite -infiles f1
nifti_tool -swap_as_old     -overwrite -infiles f1
nifti_tool -add_afni_ext 'extension in quotes' [...] -infiles f1
nifti_tool -add_comment_ext 'extension in quotes' [...] -infiles f1
nifti_tool -add_comment_ext 'file:FILENAME' [...] -infiles f1
nifti_tool -rm_ext INDEX [...] -infiles f1 ...
nifti_tool -strip_extras -infiles f1 ...
nifti_tool -diff_hdr [-field FIELDNAME] [...] -infiles f1 f2
nifti_tool -diff_nim [-field FIELDNAME] [...] -infiles f1 f2

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🌈 selected examples 🌈

these are the curated moments, the ones that really serve 💅

A. checks header (for problems):

1. nifti_tool -check_hdr -infiles dset0.nii dset1.nii
2. nifti_tool -check_hdr -infiles *.nii *.hdr
3. nifti_tool -check_hdr -quiet -infiles *.nii *.hdr

B. show header differences:

1.

nifti_tool -diff_hdr -field dim -field intent_code \
        -infiles dset0.nii dset1.nii

2.

nifti_tool -diff_hdr -new_dims 3 10 20 30 0 0 0 0 \
        -infiles my_dset.nii MAKE_IM

C. display structures or fields:

1. nifti_tool -disp_hdr -infiles dset0.nii dset1.nii dset2.nii
2. nifti_tool -disp_hdr -field dim -field descrip -infiles dset.nii
3. nifti_tool -disp_exts -infiles dset0.nii dset1.nii dset2.nii
4. nifti_tool -disp_ts 23 0 172 -infiles dset1_time.nii
5. nifti_tool -disp_ci 23 0 172 -1 0 0 0 -infiles dset1_time.nii
6. nifti_tool -disp_ana -infiles analyze.hdr
7. nifti_tool -disp_nim -infiles nifti.nii

D. create a new dataset from nothing:

1. nifti_tool -make_im -prefix new_im.nii 2.

nifti_tool -make_im -prefix float_im.nii \
        -new_dims 3 10 20 30 0 0 0 0 -new_datatype 16

3.

nifti_tool -mod_hdr -mod_field descrip 'dataset with mods' \
        -new_dims 3 10 20 30 0 0 0 0 \
        -prefix new_desc.nii -infiles MAKE_IM

E. copy dataset, brick list or collapsed image:

1. nifti_tool -copy_im -prefix new.nii -infiles dset0.nii
2. nifti_tool -cbl -prefix new_07.nii -infiles dset0.nii'[0,7]' 3.

nifti_tool -cbl -prefix new_partial.nii \
        -infiles dset0.nii'[3..$(2)]'

4. nifti_tool -cci 5 4 17 -1 -1 -1 -1 -prefix new_5_4_17.nii 5.

nifti_tool -cci 5 0 17 -1 -1 2 -1  -keep_hist \
        -prefix new_5_0_17_2.nii

F. modify the header (modify fields or swap entire header):

1.

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii \
        -mod_field dim '4 64 64 20 30 1 1 1 1'

2.

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii \
        -mod_field descrip 'beer, brats and cheese, mmmmm...'

3.

cp old_dset.hdr nifti_swap.hdr
nifti_tool -swap_as_nifti -overwrite -infiles nifti_swap.hdr

4.

cp old_dset.hdr analyze_swap.hdr
nifti_tool -swap_as_analyze -overwrite -infiles analyze_swap.hdr

5.

nifti_tool -swap_as_old -prefix old_swap.hdr -infiles old_dset.hdr
nifti_tool -diff_hdr -infiles nifti_swap.hdr old_swap.hdr

G. strip, add or remove extensions:

(in example #3, the extension is copied from a text file 👀)

1. nifti_tool -strip_extras -overwrite -infiles *.nii 2.

nifti_tool -add_comment 'converted from MY_AFNI_DSET+orig' \
        -prefix dnew -infiles dset0.nii

3.

nifti_tool -add_comment 'file:my.extension.txt' \
        -prefix dnew -infiles dset0.nii

4. nifti_tool -rm_ext ALL -prefix dset1 -infiles dset0.nii 5.

nifti_tool -rm_ext 2 -rm_ext 3 -rm_ext 5 -overwrite \
        -infiles dset0.nii

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🔍 options for check actions

• -check_hdr — check for a valid nifti_1_header struct

this action is what you use to check the nifti_1_header structure for problems, bestie. the nifti_hdr_looks_good() function does the test, and right now it checks:

• dim[]
• sizeof_hdr
• magic
• datatype

more tests can be requested of the author 👑

e.g. perform checks on the headers of some datasets

nifti_tool -check_hdr -infiles dset0.nii dset1.nii
nifti_tool -check_hdr -infiles *.nii *.hdr

e.g. add the -quiet option, so that only errors are reported

nifti_tool -check_hdr -quiet -infiles *.nii *.hdr

• -check_nim — check for a valid nifti_image struct

this action checks the nifti_image structure for problems. it gets tested via both nifti_convert_nhdr2nim() and nifti_nim_is_valid(), though other functions are called below them, of course. current checks are:

• dim[]
• sizeof_hdr
• datatype
• fname
• iname
• nifti_type

😭 heads up: creation of a nifti_image structure depends on good header fields. so errors are terminal, meaning this check would probably report at most one error, even if more exist. the -check_hdr action is more complete.

more tests can be requested of the author ✨

e.g.

nifti_tool -check_nim -infiles dset0.nii dset1.nii

e.g.

nifti_tool -check_nim -infiles *.nii *.hdr

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🦋 options for create action

• -make_im — create a new dataset from nothing

with this, the user can create a new dataset of a basic style, which can then be modified with other options. this will create zero-filled data of the appropriate size 💖

the default is a 1x1x1 image of shorts. these settings can be modified with the -new_dim option, to set the 8 dimension values, and the -new_datatype, to provide the integral type for the data.

see -new_dim, -new_datatype and -infiles for more information.

🫶 note: any -infiles dataset of the name MAKE_IM will also be created on the fly.

• -new_dim D0 .. D7 — specify the dim array for the a new dataset.

e.g. -new_dim 4 64 64 27 120 0 0 0

this dimension list will apply to any dataset created via MAKE_IM or -make_im. all 8 values are required. recall that D0 is the number of dimensions, and D1 through D7 are the sizes 👑

• -new_datatype TYPE — specify the dim array for the a new dataset.

e.g. -new_datatype 16

default: -new_datatype 4 (short)

This dimension list applies to any dataset you create via MAKE_IM or -make_im. And TYPE? bestie, it has to be one of the NIFTI_TYPE_* numbers, straight out of nifti1.h. no substitutions, okay? 💅

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✨ options for copy actions ✨

• -copy_brick_list — copy a list of volumes to a new dataset
• -cbl — (a shorter, alternative form)
• -copy_im — (a shorter, alternative form)

Okay so this action lets you copy a list of volumes (over time ⏰) from one dataset to another. The listed volumes can be in any order and can contain repeats, but they're of course restricted to the set of values {1, 2, ..., nt-1}, from dimension 4.

This option is a flag. The index list is specified with the input dataset, contained in square brackets. 📎

⚠️ Note that square brackets are special to most UNIX shells, so they should be contained within single quotes. Shell will absolutely do the wrong thing otherwise, iykyk.

Syntax of an index list, aka the notes you actually need:

• indices start at zero
• indices end at nt-1, which has the special symbol $
• single indices should be separated with commas, ,

e.g.

-infiles dset0.nii'[0,3,8,5,2,2,2]'

• ranges may be specified using .. or -

e.g.

-infiles dset0.nii'[2..95]'

e.g.

-infiles dset0.nii'[2..$]'

• ranges may have step values, specified in ()

example: 2 through 95 with a step of 3, i.e. {2,5,8,11,...,95}

e.g.

-infiles dset0.nii'[2..95(3)]'

This functionality applies only to 3 or 4-dimensional datasets. fr fr.

e.g. to copy a dataset:

nifti_tool -copy_im -prefix new.nii -infiles dset0.nii

e.g. to copy sub-bricks 0 and 7:

nifti_tool -cbl -prefix new_07.nii -infiles dset0.nii'[0,7]'

e.g. to copy an entire dataset:

nifti_tool -cbl -prefix new_all.nii -infiles dset0.nii'[0..$]'

e.g. to copy every other time point, skipping the first three:

nifti_tool -cbl -prefix new_partial.nii \
        -infiles dset0.nii'[3..$(2)]'

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• -copy_collapsed_image ... — copy a list of volumes to a new dataset
• -cci I J K T U V W — (a shorter, alternative form)

This action lets you copy a collapsed dataset, where some dimensions are collapsed to a given index. Like, the X dimension could be collapsed to i=42, and the time dimensions could be collapsed to t=17. To collapse a dimension, set Di to the desired index, where i is in {0..ni-1}. And any dimension that should not be collapsed has to be listed as -1. 🫶

Any number (of valid) dimensions can be collapsed, even down to a single value, by specifying enough valid indices. The resulting dataset will then have a reduced number of non-trivial dimensions. ✨

Assume dset0.nii has nim->dim[8] = { 4, 64, 64, 21, 80, 1, 1, 1 }. Note that this is a 4-dimensional dataset.

e.g. copy the time series for voxel i,j,k = 5,4,17

nifti_tool -cci 5 4 17 -1 -1 -1 -1 -prefix new_5_4_17.nii

e.g. read the single volume at time point 26

nifti_tool -cci -1 -1 -1 26 -1 -1 -1 -prefix new_t26.nii

Assume dset1.nii has nim->dim[8] = { 6, 64, 64, 21, 80, 4, 3, 1 }. Note that this is a 6-dimensional dataset.

e.g. copy all time series for voxel i,j,k = 5,0,17, with v=2 (and add the command to the history)

nifti_tool -cci 5 0 17 -1 -1 2 -1 -keep_hist \
        -prefix new_5_0_17_2.nii

e.g. copy all data where i=3, j=19 and v=2

(I do not claim to know a good reason to do this 🙈)

nifti_tool -cci 3 19 -1 -1 -1 2 -1 -prefix new_mess.nii

See -disp_ci for more information (which displays/prints the data, instead of copying it to a new dataset). 👑

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🦋 options for display actions 🦋

• -disp_hdr — display nifti_1_header fields for datasets

This flag means you want to see some of the nifti_1_header fields in one or more nifti datasets. You may want to specify multiple -field options along with this. This option requires one or more files input, via -infiles.

If no -field option is present, all fields will be displayed. 🌈

e.g. to display the contents of all fields:

nifti_tool -disp_hdr -infiles dset0.nii
nifti_tool -disp_hdr -infiles dset0.nii dset1.nii dset2.nii

e.g. to display the contents of select fields:

nifti_tool -disp_hdr -field dim -infiles dset0.nii
nifti_tool -disp_hdr -field dim -field descrip -infiles dset0.nii

• -disp_nim — display nifti_image fields for datasets

This flag option works the same way as the -disp_hdr option, except that the fields in question are from the nifti_image structure. 💫

• -disp_ana — display nifti_analyze75 fields for datasets

This flag option works the same way as the -disp_hdr option, except that the fields in question are from the nifti_analyze75 structure. 💫

• -disp_exts — display all AFNI-type extensions

This flag option is used to display all nifti_1_extension data, for only those extensions of type AFNI (code = 4). The only other option used will be -infiles.

e.g. to display the extensions in datasets:

nifti_tool -disp_exts -infiles dset0.nii
nifti_tool -disp_exts -infiles dset0.nii dset1.nii dset2.nii

• -disp_ts I J K — display ASCII time series at i,j,k = I,J,K

This option is used to display the time series data for the voxel at i,j,k indices I,J,K. The data is displayed in text, either all on one line (the default), or as one number per line (via the -dci_lines option).

Notes:

• This function applies only to 4-dimensional datasets.
• The -quiet option can be used to suppress the text header, leaving only the data.
• This option is short for using -disp_ci (display collapsed image), restricted to 4-dimensional datasets. i.e.:

-disp_ci I J K -1 -1 -1 -1

e.g. to display the time series at voxel 23, 0, 172:

nifti_tool -disp_ts 23 0 172            -infiles dset1_time.nii
nifti_tool -disp_ts 23 0 172 -dci_lines -infiles dset1_time.nii
nifti_tool -disp_ts 23 0 172 -quiet     -infiles dset1_time.nii

• -disp_collapsed_image — display ASCII values for collapsed dataset
• -disp_ci I J K T U V W — (a shorter, alternative form)

This option is used to display all of the data from a collapsed image, given the dimension list. The data is displayed in text, either all on one line (the default), or as one number per line (by using the -dci_lines flag). ✨

The -quiet option can be used to suppress the text header.

e.g. to display the time series at voxel 23, 0, 172:

nifti_tool -disp_ci 23 0 172 -1 0 0 0 -infiles dset1_time.nii

e.g. to display z-slice 14, at time t=68:

nifti_tool -disp_ci -1 -1 14 68 0 0 0 -infiles dset1_time.nii

See -ccd for more information, which copies such data to a new dataset, instead of printing it to the terminal window. 🎀

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💜 options for modification actions 💜

• -mod_hdr — modify nifti_1_header fields for datasets

This action is used to modify some of the nifti_1_header fields in one or more datasets. You must specify a list of fields to modify via one or more -mod_field options, which include field names, along with the new (set of) values.

You can modify a dataset in place, or use -prefix to produce a new dataset, to which the changes have been applied. It is recommended to normally use the -prefix option, so as not to ruin a dataset. 😭 don't ruin your dataset bestie.

Note that some fields have a length greater than 1, meaning that the field is an array of numbers, or a string of characters. In order to modify an array of numbers, you must provide the correct number of values, and contain those values in quotes, so that they are seen as a single option.

To modify a string field, put the string in quotes.

The -mod_field option takes a field_name and a list of values.

e.g. to modify the contents of various fields:

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii \
        -mod_field qoffset_x -17.325

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii \
        -mod_field dim '4 64 64 20 30 1 1 1 1'

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii \
        -mod_field descrip 'beer, brats and cheese, mmmmm...'

e.g. to modify the contents of multiple fields:

nifti_tool -mod_hdr -prefix dnew -infiles dset0.nii  \
        -mod_field qoffset_x -17.325 -mod_field slice_start 1

e.g. to modify the contents of multiple files (must overwrite):

nifti_tool -mod_hdr -overwrite -mod_field qoffset_x -17.325   \
        -infiles dset0.nii dset1.nii

• -mod_nim — modify nifti_image fields for datasets

This action option is used the same way that -mod_hdr is used, except that the fields in question are from the nifti_image structure. 💫

• -strip_extras — remove extensions and descriptions from datasets

This action is used to attempt to 'clean' a dataset of general text, in order to make it more anonymous. Extensions and the nifti_image descrip field are cleared by this action. 🧼✨

e.g. to strip all *.nii datasets in this directory:

nifti_tool -strip_extras -overwrite -infiles *.nii

• -swap_as_nifti — swap the header according to nifti_1_header

Perhaps a NIfTI header is mal-formed, and you explicitly want to swap it before performing other operations. This action will swap the field bytes under the assumption that the header is in the NIfTI format.

🚨 The recommended course of action is to make a copy of the dataset and overwrite the header via -overwrite. If the header needs such an operation, it is likely that the data would not otherwise be read in correctly. like, seriously, back it up first. 💀

• -swap_as_analyze — swap the header according to nifti_analyze75

Perhaps an ANALYZE header is mal-formed, and you explicitly want to swap it before performing other operations. This action will swap the field bytes under the assumption that the header is in the ANALYZE 7.5 format.

The recommended course of action is to make a copy of the dataset and overwrite the header via -overwrite. If the header needs such an operation, it is likely that the data would not otherwise be read in correctly. 💅

• -swap_as_old — swap the header using the old method

Okay so bestie, as of library version 1.35 (3 Aug, 2008), nifticlib now swaps all fields of a NIfTI dataset (including UNUSED ones), and it swaps ANALYZE datasets according to the nifti_analyze75 structure. This is a significant difference in the case of ANALYZE datasets. 😭

The -swap_as_old option was added to compare the results of the swapping methods, or to undo one swapping method and replace it with another (such as to undo the old method and apply the new). It's giving time travel but for headers. ✨

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✨ options for adding/removing extensions ✨

• -add_afni_ext EXT — add an AFNI extension to the dataset

This option is used to add AFNI-type extensions to one or more datasets. This option may be used more than once to add more than one extension. Lowkey stacking them like bracelets. 🫶

If EXT is of the form 'file:FILENAME', then the extension will be read from the file, FILENAME.

The -prefix option is recommended, to create a new dataset. In such a case, only a single file may be taken as input. Using -overwrite allows the user to overwrite the current file, or to add the extension(s) to multiple files, overwriting them. Choose your fighter. 💅

e.g. to add a generic AFNI extension:

nifti_tool -add_afni_ext 'wow, my first extension' -prefix dnew -infiles dset0.nii

e.g. to add multiple AFNI extensions:

nifti_tool -add_afni_ext 'wow, my first extension :)' -add_afni_ext 'look, my second...' -prefix dnew -infiles dset0.nii

e.g. to add an extension, and overwrite the dataset:

nifti_tool -add_afni_ext 'some AFNI extension' -overwrite -infiles dset0.nii dset1.nii

• -add_comment_ext EXT — add a COMMENT extension to the dataset

This option is used to add COMMENT-type extensions to one or more datasets. This option may be used more than once to add more than one extension. This option may also be used with -add_afni_ext. Bestie behavior, fr fr. 🎀

If EXT is of the form 'file:FILENAME', then the extension will be read from the file, FILENAME.

The -prefix option is recommended, to create a new dataset. In such a case, only a single file may be taken as input. Using -overwrite allows the user to overwrite the current file, or to add the extension(s) to multiple files, overwriting them.

e.g. to add a comment about the dataset:

nifti_tool -add_comment 'converted from MY_AFNI_DSET+orig' -prefix dnew -infiles dset0.nii

e.g. to add multiple extensions:

nifti_tool -add_comment 'add a comment extension' -add_afni_ext 'and an AFNI XML style extension' -add_comment 'dataset copied from dset0.nii' -prefix dnew -infiles dset0.nii

• -rm_ext INDEX — remove the extension given by INDEX

This option is used to remove any single extension from the dataset. Multiple extensions require multiple options. No cap, one at a time. 🧚

notes:

• extension indices begin with 0 (zero)
• to view the current extensions, see -disp_exts
• all extensions can be removed using ALL or -1 for INDEX

e.g. to remove the extension #0:

nifti_tool -rm_ext 0 -overwrite -infiles dset0.nii

e.g. to remove ALL extensions:

nifti_tool -rm_ext ALL -prefix dset1 -infiles dset0.nii
nifti_tool -rm_ext -1  -prefix dset1 -infiles dset0.nii

e.g. to remove the extensions #2, #3 and #5:

nifti_tool -rm_ext 2 -rm_ext 3 -rm_ext 5 -overwrite -infiles dset0.nii

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✨ options for showing differences ✨

• -diff_hdr — display header field diffs between two datasets

This option is used to find differences between two datasets. If any fields are different, the contents of those fields is displayed (unless the -quiet option is used). It's giving detective mode. 🔍

A list of fields can be specified by using multiple -field options. If no -field option is given, all fields will be checked.

Exactly two dataset names must be provided via -infiles. Not one, not three. Periodt. 💅

e.g. to display all nifti_1_header field differences:

nifti_tool -diff_hdr -infiles dset0.nii dset1.nii

e.g. to display selected nifti_1_header field differences:

nifti_tool -diff_hdr -field dim -field intent_code -infiles dset0.nii dset1.nii

• -diff_nim — display nifti_image field diffs between datasets

This option works the same as -diff_hdr, except that the fields in question are from the nifti_image structure. Same vibe, different struct. 🌈

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✨ miscellaneous options ✨

• -debug LEVEL — set the debugging level

Level 0 will attempt to operate with no screen output, but errors. Level 1 is the default. Levels 2 and 3 give progressively more information. Like turning up the volume on the tea. ☕

e.g. -debug 2

• -field FIELDNAME — provide a field to work with

This option is used to provide a field to display, modify or compare. This option can be used along with one of the action options presented above.

See -disp_hdr, above, for complete examples.

e.g. nifti_tool -field descrip e.g. nifti_tool -field descrip -field dim

• -infiles file0... — provide a list of files to work with

This parameter is required for any of the actions, in order to provide a list of files to process. If input filenames do not have an extension, the directory we be searched for any appropriate files (such as .nii or .hdr). (Yes, "we be searched" — iconic typo, we keep it. 💀)

Note: if the filename has the form MAKE_IM, then a new dataset will be created, without the need for file input.

See -mod_hdr, above, for complete examples.

e.g. nifti_tool -infiles file0.nii e.g. nifti_tool -infiles file1.nii file2 file3.hdr

• -mod_field NAME 'VALUE_LIST' — provide new values for a field

This parameter is required for any the modification actions. If the user wants to modify any fields of a dataset, this is where the fields and values are specified. (Also "any the" — we see you, original. 👀)

NAME is a field name (in either the nifti_1_header structure or the nifti_image structure). If the action option is -mod_hdr, then NAME must be the name of a nifti_1_header field. If the action is -mod_nim, NAME must be from a nifti_image structure.

VALUE_LIST must be one or more values, as many as are required for the field, contained in quotes if more than one is provided.

Use nifti_tool -help_hdr to get a list of nifti_1_header fields Use nifti_tool -help_nim to get a list of nifti_image fields

See -mod_hdr, above, for complete examples.

e.g. modifying nifti_1_header fields:

-mod_field descrip 'toga, toga, toga' -mod_field qoffset_x 19.4 -mod_field qoffset_z -11 -mod_field pixdim '1 0.9375 0.9375 1.2 1 1 1 1'

• -keep_hist — add the command as COMMENT (to the 'history')

When this option is used, the current command will be added as a NIFTI_ECODE_COMMENT type extension. This provides the ability to keep a history of commands affecting a dataset. It's giving receipts. 🧾

e.g. -keep_hist

• -overwrite — any modifications will be made to input files

This option is used so that all field modifications, including extension additions or deletions, will be made to the files that are input.

In general, the user is recommended to use the -prefix option to create new files. But if overwriting the contents of the input files is preferred, this is how to do it. Live dangerously, bestie. 🔥

See -mod_hdr or -add_afni_ext, above, for complete examples.

e.g. -overwrite

• -prefix — specify an output file to write change into

This option is used to specify an output file to write, after modifications have been made. If modifications are being made, then either -prefix or -overwrite is required.

If no extension is given, the output extension will be .nii.

e.g. -prefix new_dset e.g. -prefix new_dset.nii e.g. -prefix new_dset.hdr

• -quiet — report only errors or requested information

This option is equivalent to -debug 0. Shhh. 🤫

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✨ basic help options ✨

• -help — show this help

e.g. nifti_tool -help

• -help_hdr — show nifti_1_header field info

e.g. nifti_tool -help_hdr

• -help_nim — show nifti_image field info

e.g. nifti_tool -help_nim

• -help_ana — show nifti_analyze75 field info

e.g. nifti_tool -help_ana

• -help_datatypes [TYPE] — display datatype table

e.g. nifti_tool -help_datatypes

e.g. nifti_tool -help_datatypes N

This displays the contents of the nifti_type_list table. An additional 'D' or 'N' parameter will restrict the type name to 'DT_' or 'NIFTI_TYPE_' names, 'T' will test.

• -ver — show the program version number

e.g. nifti_tool -ver

• -hist — show the program modification history

e.g. nifti_tool -hist

• -nifti_ver — show the nifti library version number

e.g. nifti_tool -nifti_ver

• -nifti_hist — show the nifti library modification history

e.g. nifti_tool -nifti_hist

• -with_zlib — print whether library was compiled with zlib

e.g. nifti_tool -with_zlib

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R. Reynolds compiled: Jul 24 2025 version 1.24 (September 26, 2012)

source: nifti1_tool, version 1.24 (Sept... July 2025), manual page NIFTI1_TOOL,(1). 💖✨