Offline editing is the creative storytelling stage of film and television production where the structure, mood, pacing and story of the final show are defined.
This is when the process then moves on to the next stages of post production known as online editing, colour grading and audio mixing.
Editing the copy allows multiple story and creative possibilities to be explored without affecting the camera original film stock or video tape.
When two-inch quadraplex video tape recording was first introduced by Ampex in 1956, it could not be physically cut and spliced simply and cleanly as film negatives could be.
Three developments of the late sixties and early seventies revolutionized video editing, and made it possible for television to have its own version of the film workprint/conform process.
Although video technology had the potential to be cheaper since it doesn't have the costs of film stock and have to go through the development process respectively, the quality of early video recording technology in the 1950s and even into the mid 1960s was often far too low to be taken seriously against the aesthetical look, familiarity and relative ease of editing of 16mm and 35mm film stock – which many television cinematographers used well up until the late 1980s in documentaries, dramas etc.
They might simply write them in a list, or they might dub from one of these small machines to another to create a rough cut edit, and note the necessary frame numbers by watching this tape.
Camera master tapes were dubbed as black and white analog video to very large computer memory discs.
The editor could access any shot exactly, and quickly edit a precise black and white, low quality version of the program.
The computer kept track of all the numbers in this offline stage of the process, and when the editor was satisfied, output them as an Edit decision list (EDL).
To make it work, special computer to video tape recorder (VTR) edit interfaces had to be developed, called I-Squareds.
Although tape formats changed from open reels to videocassettes (VCR), and all the equipment rapidly became much cheaper, the basics of the process remained the same.