The Movie Atom

QuickTime Movie File Format Specification, May 1996

The Movie Atom

You use movie atoms to specify the information that defines a movie--that is, the information that allows your application to understand the data that is stored in the movie data atom. The movie atom contains the movie header atom, which defines the time scale and duration information for the entire movie, as well as its display characteristics. In addition, the movie atom contains each track in the movie.

The movie atom has an atom type of ' moov' . It contains other types of atoms, including one leaf atom--the movie header ('mvhd' )--and several atoms that contain other atoms: a clipping atom ('clip' ), one or more track atoms ('trak' ), a color table atom ('ctab' ), and user data ('udta' ).

Figure 0-6 shows the layout of a movie atom. The movie header atom is the only required atom in the movie atom.

Figure 6 The layout of a movie atom

A movie atom contains the following information.

Size: The number of bytes in this movie atom.
Type: The type of this movie atom; this field must be set to 'moov' .
Movie header: The movie header atom associated with this movie. See the next section for details on the movie header atom.
Movie clipping atom: The clipping atom associated with this movie. See "Clipping Atoms," beginning on [link] , for more information.
Track list: One or more track atoms associated with this movie. See "Track Atoms," beginning on [link] , for details on track atoms and their associated atoms.
User data: The user data atom associated with this movie. See "User Data Atoms" for more information about user data atoms.
Color table: The color table atom associated with this movie. See "Color Table Atoms" for a discussion of the color table atom.

Movie Header Atoms

Color Table Atoms