convert 3d+t to rgb?

Hi, does anyone know how to convert a 3d+t (3 time points) image to rgb?

i have freesurfer white matter surface normals in the 3d+t volume format (t0=x, t1=y, t2=z), and i would like to convert it into a tensor or RGB nifti for visualization in another software package.

thanks,

Russell

3dThreetoRGB