## QMedia v1.5 | ## Introducing QuickTime

Home | Time management | Tracks | QTVR movies | Standard properties | Controller Properties | VR properties | Track properties | Editing

## Movie Tracks

A movie can contain one or more tracks. Each track has a single media type (e.g. video, text, sound, etc) and represents a single stream of data.

- All tracks of the same movie use the movie's time coordinate system.
- Tracks begin at the beginning of the movie (time 0), but their duration may be shorter than the movie duration.
- Track data may be offset from the beginning of the movie, in which case the track contains empty space before its data.
- Tracks may be enabled or disabled. When the movie plays, QuickTime gathers information from all enabled tracks and plays their media accordingly.

Movie playback is accomplished with the help of movie controllers. Movie controllers present the necessary user interface, if any, to let the user control the playback. Currently, QuickTime 3.0 includes the following types of movie controllers for playing specific kinds of movies:

- The standard movie controller that provides the necessary controls (sound, play, step buttons) for standard movie playback.
- The QTVR movie controller that includes controls for navigating QTVR movies.
- The "none" movie controller, introduced in QT 3.0, is mainly used for interactive movies.