QuickTime 4 Reference

Data References

The Movie Toolbox now fully supports a media that refers to data in more than one file. In the past, a media was restricted to a single data file. By allowing a single media to refer to more than one file, the toolbox allows better playback performance and easier editing, primarily by reducing the number of tracks in a movie. Use the new SetMediaDefaultDataRefIndex function to control which of a media's files you access when you add new sample data.