face morphing

As you probably know this is a video from Michael Jacksons hit single Black & White. 

As well as being a brilliant catchy song his video is inspired. The face morph process is really cool and works really well in this vid. I've been looking around for the making of this video but i cant find anything, i really want to know how they make this work, what program they would have used.

I think they had to get people who's faces who were similar obvs not skin colour but shape so that they could merge together easily. I'm gonna keep looking cause i really wanna know!