Is the NIfTI-1 header extensible?
(Hester Breman) The NIfTI-1 files can exist in two forms. There can be a single *.nii file or two separate files, a *.hdr and a *.img file (see the NIfTI-1 header file for more details). When the information is separated into a *.hdr and *.img file, which resembles the original ANALYZE 7.5 format, any programs that read the ANALYZE format will expect a header of 348 bytes. Therefore the NIfTI-1 header is not extensible in this form, since any program is likely to fail when it detects that the header file is not the expected size. While it is possible to store data between the header and the image part of a single *.nii file, this is non-standard and no other program will will be able to interpret these data. Therefore it is not recommended to produce such files. In the current NIfTI-1 format, there are many possibilities to store different kinds of data in the image part of the file. Datasets, many types of statistical values, vectors, meshes, etc., all can be stored in NIfTI-1. Each N
