Read metadata from NIfTI file



info = niftiinfo(filename) returns metadata, info, from the Neuroimaging Informatics Technology Initiative (NIfTI) file specified by filename. The niftiinfo function supports both the NIfTI1 and NIfTI2 file formats.


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Load metadata from the NIfTI file brain.nii.

info = niftiinfo('brain.nii');

Display the version of the file.

ans = 

Display the pixel dimensions of the file.

ans = 1×3

     1     1     1

Display the raw header content.

ans = struct with fields:
        sizeof_hdr: 348
          dim_info: ' '
               dim: [3 256 256 21 1 1 1 1]
         intent_p1: 0
         intent_p2: 0
         intent_p3: 0
       intent_code: 0
          datatype: 2
            bitpix: 8
       slice_start: 0
            pixdim: [1 1 1 1 0 0 0 0]
        vox_offset: 352
         scl_slope: 0
         scl_inter: 0
         slice_end: 0
        slice_code: 0
        xyzt_units: 0
           cal_max: 0
           cal_min: 0
    slice_duration: 0
           toffset: 0
           descrip: ''
          aux_file: ''
        qform_code: 0
        sform_code: 0
         quatern_b: 0
         quatern_c: 0
         quatern_d: 0
         qoffset_x: 0
         qoffset_y: 0
         qoffset_z: 0
            srow_x: [0 0 0 0]
            srow_y: [0 0 0 0]
            srow_z: [0 0 0 0]
       intent_name: ''
             magic: 'n+1 '

Display the intent code from the raw structure.

ans = 0

Input Arguments

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Name of NIfTI file, specified as a string scalar or a character vector.

  • If you do not specify a file extension, then niftiinfo looks for a file with the extension .nii (or .nii.gz if the file is compressed).

  • If niftiinfo cannot find a file with the .nii or .nii.gz extension, then it looks for a file with the file extension .hdr (or .hdr.gz if the file is compressed). In the dual-file NIfTI format, the .hdr file holds the metadata associated with the volume.

Data Types: char | string

Output Arguments

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Metadata associated with a NIfTI volume, returned as a structure.

niftiinfo returns the metadata from the header in simplified form. The function renames, reorders, and packages fields into easier to read MATLAB® structures. For example, niftiinfo creates the DisplayIntensityRange field from the cal_max and cal_min fields of the file metadata. To view the metadata as it appears in the file, see the raw field of the structure returned.


[1] Cox, R. W., J. Ashburner, H. Breman, K. Fissell, C. Haselgrove, C. J. Holmes, J. L. Lancaster, D. E. Rex, S. M. Smith, J. B. Woodward, and S. C. Strother. "A (sort of) new image data format standard: NiFTI-1." 10th Annual Meeting of Organisation of Human Brain Mapping, Budapest, Hungary, June 2004.

Introduced in R2017b