Quicktime File Format (2012-08-14).pdf

Some Useful Examples and ScenariosAuthoring Movies with External Movie TargetsWhen a modifier track is playing an empty track edit, or is disabled or deleted, all receiving tracks are notifiedthat the track input is inactive. When an input becomes inactive, it is reset to its default value. For example, ifa track is receiving data from a clip modifier track and that input becomes inactive, the shape of the trackreverts to the shape it would have if there were no clip modifier track.Authoring Movies with External Movie TargetsQuickTime 4 enables you to author movies with external movie targets. To specify an action that targets anelement of an external movie, you must identify the external movie by either its name or its ID. Two new targetatom types have been introduced for this purpose; these atoms are used in addition to the existing targetatoms, which you may use to specify that the element is a particular track or object within a track, such as asprite.Note A movie ID may be specified by an expression.These additional target atoms provided in QuickTime 4:[(ActionTargetAtoms)] =[Pstring MovieName]OR[long MovieID]OR[(kExpressionAtoms)]To tag a movie with a name or ID, you add a user data item of type 'plug' to the movie’s user data. The indexof the user data does not matter. The data specifies the name or ID.You add a user data item of type 'plug' to the movie’s user data with its data set to"Movieid=MovieName"where MovieName is the name of the movie.2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.345