PowerPoint Presentation

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NIfTI Dataset Files

• NIfTI-1.1 (.nii or .nii.gz) is a new standard format that AFNI, SPM, FSL, BrainVoyager, et al., have agreed upon

H Adaptation and extension of the old ANALYZE 7.5 format

H Goal: easier interoperability of tools from various packages

• All data is stored in 1 file (cf. http://nifti.nimh.nih.gov/)

H 348 byte header (extensions allowed; AFNI uses this feature)

H Followed by the image numerical values

H Allows 1D-5D datasets of diverse numerical types

H .nii.gz suffix means file is compressed (with gzip)

• AFNI now reads and writes NIfTI-1.1 formatted datasets

H To write: when you give the prefix for the output filename, end it in “.nii” or “.nii.gz”, and all AFNI programs will automatically write NIfTI-1.1 format instead of .HEAD/.BRIK

H To read: just give the full filename ending in “.nii” or “.nii.gz”