Hi Tejas,
I think modern Philips scanners have some ability to
directly write NIfTI files, though last I knew, they
were writing the transformation incorrectly.
Otherwise, most major FMRI software packages should
be able to write it easily. In AFNI, you can write
NIfTI just by including the .nii suffix in the output
prefix of a command. Three examples:
3dcopy my_dset+orig new_dset.nii
to3d -prefix anat.nii anat*.dcm
3dbucket -prefix new_buck.nii stats1+orig'[0..4]' stats2+orig'[11..$]'
- rick