Non-linear editing system

A non-linear editing system (NLE) is a video (NLVE) or audio editing (NLAE) digital audio workstation (DAW) system that performs non-destructive editing on source material. The name is in contrast to 20th century methods of linear video editing and film editing.

Linear and non-linear editing

Non-linear editing is the most natural approach when all assets are available as files on video servers or hard disks, rather than recordings on reels or tapes—while linear editing is tied to the need to sequentially view film or hear tape.

Metadata

When ingesting audio or video feeds, metadata are attached to the clip. Those metadata can be attached automatically (timecode, localization, take number, name of the clip) or manually (players names, characters, in sports: red card, goal...).

Direct access

Non-linear editing enables direct access to any video frame in a digital video clip, without needing to play or scrub/shuttle through adjacent footage to reach it, as was necessary with historical video tape linear editing systems. It is now possible to access any frame by entering directly the timecode or the descriptive metadata. An editor can, for example at the end of the day in the Olympic Games, ask to retrieve all the clips related to the players who received a gold medal.

Linear video editing

Linear video editing is a video editing post-production process of selecting, arranging and modifying images and sound in a predetermined, ordered sequence. Regardless of whether it was captured by a video camera, tapeless camcorder, or recorded in a television studio on a video tape recorder (VTR) the content must be accessed sequentially. For the most part video editing software has replaced linear editing.

Until the advent of computer-based random access non-linear editing systems (NLE) in the early 1990s "linear video editing" was simply called "video editing".

History

Live television is still basically produced in the same manner as it was in the 1950s, although transformed by modern technical advances. Before videotape, the only way of airing the same shows again was by filming shows using a kinescope, essentially a video monitor paired with a movie camera. However, kinescopes (the films of television shows) suffered from various sorts of picture degradation, from image distortion and apparent scan lines to artifacts in contrast and loss of detail. Kinescopes had to be processed and printed in a film laboratory, making them unreliable for broadcasts delayed for different time zones.