ABSTRACT
For many years, people working with film have employed a system of film footage numbering, commonly called 'key numbers'. These are printed along the edge of film stock at the time of manufacture as a latent image, becoming human-readable when the film is processed. The purpose of these numbers has been to facilitate the work of the negative cutter, once the film editor has done his or her work (Figure 5.1). In addition to the key number, a 'strip number', having a random relationship to the key number, has also been present to act as a check in the event of duplicated key numbers (always a possibility with a full-length feature film, where hundreds of thousands of feet of film may have been shot). The key number identifies the film type, the printer number (part of the quality control system), the perforation equipment and the footage count. As some scenes may be less than 1 ft long (especially in pop music videos) there may be no key number present in a particular shot. Recent developments in film production have resulted in the marriage of traditional film numbering systems with timecode. This chapter examines the coding systems available, together with the options expected to be developed in the near future.
