Difference between fftn and fft2

[JKaskou]

Hello everybody,

I am trying to understand how the Wiener filter is programmed inside Matlab and I don't understand why fftn is used rather than fft2 to compute the numerator (called nomin here) :

Nomin = conj(otf).*fftn(I);

Is it because of speed gain or a dimension concern ?

Thanks in advance for any help.

Kaskou