Hi Antonio,
In short, no. :)
All of those dataset formats (NIfTI, ANALYZE, AFNI) have the
applied endian checked when they are read in (to AFNI). If
they are not the same as your CPU, they are converted to it
before processing.
Datasets are output in the endian of the CPU. But again, that
really doesn't matter, as long as it can be figured out.
- rick