NLE
Non-Linear (Video) Editing system: in contrast to the older Linear video editing system, which operated by writing video segments to tape, starting at the beginning of the program and working to the end. If a program was to be lengthened or shortened, everything from the cut point until the end would have to be re-edited - or else "dubbed", losing a generation of quality. Needless to say, this was very restrictive.
All modern digital video editing systems are non-linear[citation needed], allowing the (human) editor to insert, delete, trim and move segments at will. Avisynth is a type of NLE (the world's smallest by a factor of 500), as changing clips around, lengthening or trimming them, is very simple and straightforward.
Example
Suppose we start with the following clips, and we want to assemble a program:
clip_intro = AviSource("intro.avi") clip_main = AviSource("main.avi") clip_outro = AviSource("outro.avi") B = BlankClip(clip_main)
Here is our first edit:
edit_1 = clip_intro \ ++ B.Trim(0, -15) \ ++ clip_main \ ++ clip_outro return edit_1
We find it runs a little too long, but it's easy trim it down a bit here and there:
edit_2 = clip_intro \ .Trim(0, clip_intro.FrameCount-5) \ ++ B.Trim(0, -15) \ ++ clip_main \ .Trim(0, 12345) \ ++ clip_main \ .Trim(12390, 0) \ .FadeOut(15) \ ++ clip_outro \ .FadeIn(15) return edit_2
