Module io 

NIfTI file I/O for WASM

Provides functions to load and save NIfTI files from/to byte arrays, suitable for use in WebAssembly where filesystem access is not available.

Structs

NiftiData

NIfTI data loaded from bytes

QForm 🔒

NIfTI-1’s quaternion (“qform”) description of a voxel→world transform — method 2 in the spec.

Constants

NIFTI_XYZT_UNITS

xyzt_units for every file this crate writes: NIFTI_UNITS_MM | NIFTI_UNITS_SEC.

Functions

affine_from_quatern 🔒

Rebuild the voxel→world affine a reader derives from a qform — the spec’s nifti_quatern_to_mat44. pixdim is pixdim[1..=3] as it appears in the header.

encode_nifti 🔒

Encode volumes (each nx*ny*nz values, x fastest) as an uncompressed NIfTI-1 file, 3D (four_d = false, exactly one volume) or 4D (dim[4] = volumes.len()). Both writers share this, so they cannot disagree on the header: float32 data, unit scaling, sform plus a matching qform where one exists, and NIFTI_XYZT_UNITS.

get_affine 🔒

Get affine transformation matrix from header

get_header_info 🔒

Get header info for diagnostics

gzip 🔒

is_gzip 🔒

Check if bytes are gzip compressed

load_itk_geometry

The image geometry ITK (ITK 5.3, as in ANTs 2.4.3) reads from a NIfTI file’s header (ItkGeometry::from_nifti_header), for ports whose output depends on it (n4_bias_correction). Supports .nii and .nii.gz bytes.

load_nifti

Load a NIfTI file from bytes

load_nifti_4d

Load a 4D NIfTI file from bytes (for multi-echo data)

qform_for 🔒

The qform to write alongside an sform, or None when no quaternion reproduces the affine.

quatern_from_affine 🔒

Decompose a row-major voxel→world affine into its quaternion form, following the NIfTI-1 spec’s nifti_mat44_to_quatern.

read_itk_geometry_file

load_itk_geometry of a file.

read_nifti_dims

Read only the dimensions from a NIfTI file header without loading volume data.

read_nifti_file

Read a NIfTI file from a filesystem path

save_nifti

Save data as NIfTI bytes

save_nifti_4d

Save several 3D volumes on one grid as a single uncompressed 4D NIfTI file.

save_nifti_4d_gz

save_nifti_4d, gzipped (.nii.gz).

save_nifti_4d_to_file

Save several 3D volumes as one 4D NIfTI file (see save_nifti_4d).

save_nifti_gz

Save data as gzipped NIfTI bytes (.nii.gz)

save_nifti_to_file

Save NIfTI data to a file

Type Aliases

Nifti4d

A loaded 4D volume: (data, (nx, ny, nz, nt), (vsx, vsy, vsz), affine).