CIFTI
CIFTI is a file format that
stores data from surfaces (vertices) and volumes (voxels)
concurrently in a single file comprising a listed set of brainordinates. A
CIFTI file can contain multiple non-overlapping volume
components with different structures, where each volume
component is any selected list of voxels (e.g., only left thalamus
voxels). These components need not fill the entire grid of
‘N x M x O’ volumetric dimensions. A CIFTI file can also
include multiple surface components with different structures
(most commonly, the left and right cerebral cortex), but the
surface geometry is not specified in the CIFTI file (commonly, the
geometry is in a separate GIFTI
surface file). See http://www.nitrc.org/projects/cifti/
for a detailed exposition of the CIFTI-2 file format.
CIFTI files are based on the NIFTI-2 file format
and therefore have a filename extension ending in .nii.
Workbench currently supports many types of CIFTI files,
including dense scalar (*.dscalar.nii), dense data series
(*.dtseries.nii), dense connectome (*.dconn.nii), and dense label
(*.dlabel.nii), where the term 'dense' refers to having a value at
each listed brainordinate (as opposed to a parcellated file such
as *.ptseries.nii, where each value is shared across many
brainordinates). Files in the now-deprecated CIFTI-1 format are
still supported by Workbench and can be converted to CIFTI-2
using: wb_command -file-convert -cifti-version-convert.