Offline editing

Offline editing is part of the post-production process of filmmaking and television production in which raw footage is copied and edited, without affecting the camera original or video tape. Once the project has been completely offline edited, the original media will be assembled in the online editing stage.

The term offline originated in the computing and telecommunications industries, meaning "not under the direct control of another device" (automation).

Modern offline video editing is conducted in a non-linear editing (NLE) suite. The digital revolution has made the offline editing workflow process immeasurably quicker, as practitioners moved from time-consuming (video tape to tape) linear video editing online editing suites, to computer hardware and video editing software such as Adobe Premiere, Final Cut Pro, Avid, Sony Vegas, Lightworks and VideoPad. Typically, all the original footage (often tens or hundreds of hours) is digitized into the suite at a low resolution. The editor and director are then free to work with all the options to create the final cut.

Film editing used an offline approach almost from the beginning. Film editors worked with a workprint of the original film negative to protect the negative from handling damage. When two-inch quadraplex video tape recording was first introduced by Ampex in 1956, it could not be physically cut and spliced as simply and cleanly as film negatives could be. One error-prone method option was to cut the tape with a razor blade. Since there was no visible frame line on the 2-inch-wide (51 mm) tape, a special ferrofluid developing solution was applied to the tape, allowing the editor to view the recorded control track pulse under a microscope, and thus determine where one frame ended and the next began. This process was not always exact, and if imperfectly performed would lead to picture breakup when the cut was played. Generally this process was used to assemble scenes together, not for creative editing.

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