Mellotron; no.
Realtracks are much more involved than that.

Realtracks-
Studio musicians record tracks in different styles.
They may have recorded the original tracks (which you can listen to by the way) using E-D-C-B progression (at tempo=108).
Then you tell BiaB you want this 'style' recording using E-B-A-G chords (at tempo=112).
Realtracks will take the recorded licks, pitch shift and and adjust tempo, and have the recording played with the chords and tempo you selected. Major tech accomplshment IMO. Very impressive when compared to loops and sampling.


Regenerating gives different varieties; another even more impressive feat.
They really are quite an improvement to other options. I think they are a new innovation that will change a lot of other software. eventually..

I do not work here, but the benefits are still awesome
Make your sound your own!