Hi
Yes - there are two ways video editing programs can do this
• iMovie way
• Every body else as FinalCut
In iMovie the material to build up the transition is borrowed from prior clip and following clip - result is time of movie is not changed.
In all other video editors one works with clip handles. A needed clip is marked with an in- resp. out-point leaving some few (or many) seconds not used in both ends. And transitions here use this Clip-Handle to build up the transition. Result is that over all movie duration increases with number of transitions - but each clip in the movie is kept in full.
I do in iMovie up to HD6 do (but this should work in any version).
• Take last frame as a still photo and then add it after this clip.
• Set duration of this last frame to more than half the time of the transition.
• Then introduce transition in between this still and next clip
Now first clip will play in full till transition.
This can be applied to the first part of the second clip too - if start of this also has to be un-touched.
Yours Bengt W