Edit decision list

An edit decision list or EDL is used in the post-production process of film editing and video editing. The list contains an ordered list of reel and timecode data representing where each video clip can be obtained in order to conform the final cut.

EDLs are created by offline editing systems, or can be paper documents constructed by hand such as shot logging. These days, linear video editing systems have been superseded by non-linear editing (NLE) systems which can output EDLs electronically to allow on an online editing system – the recreation of an edited programme from the original sources (usually video tapes) and the editing decisions in the EDL.

They are also often used in the digital video editing world, so rather than referring to reels they can refer to sequences of images stored on disk.

Some formats, such as CMX3600, can represent simple editing decisions only. Final Cut Pro XML, the Advanced Authoring Format (AAF), and AviSynth scripts are relatively advanced file formats that can contain sophisticated EDLs.

Linear editing systems cannot dissolve between clips on the same video tape. Hence, one of these clips will need to be dubbed onto a new video tape. EDLs designate these occurrences by marking such dissolves' source reels as B-roll of "b-reels". For example, the EDL will change the 8th character of the reel name to the letter B.

However, sometimes editors will (confusingly) use the letter B to designate time code breaks on a video tape. If there is broken time code on a video tape, there will be two (or more) instances of a particular time code on the video tape. When re-capturing, it can be ambiguous as to which timecode is the right one. The letter B may indicate that the right time code is from the second set of timecode on the video tape.

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