scope:

This document specifies the Composition Playlist structure. The Composition Playlist is a self-contained representation of a single complete D-Cinema work, such as a motion picture, or a trailer, or an advertisement, etc. The Composition Playlist consists of an ordered sequence of Reel structures, each referencing a set of external Track Files, e.g. a sound or picture Track File, which are meant to be reproduced in parallel. Each Reel is analogous to a film reel and the Composition Playlist controls the order and timing of the playout of the Reels.