afni.nimh.nih.gov

We used 3dZeroPad to add extra space in the z direction to allow for some nudging of EPI data, but now we have a bunch of extra zero-space to the negative end of the dataset. In other words, our EPI is not centered vertically anymore (more zero-space in the negative direction) Is there a way to remove this extra space?

I tried 3dZeropad with a negative Z value, but that takes from both upper and lower ends of the dataset. Is there a way to selectively take from the bottom only?