QuickTime 4 Reference

About the Tween Media Handler

A tween track is a special track in a movie that is used exclusively as a modifier track. The data it contains, known as tween data, is used to generate values that modify the playback of other tracks, usually by interpolating values. The tween media handler sends these values to other media handlers; it never presents data. For an introduction to modifier tracks, see "Modifier Tracks" (page 46) .

Typical tween components can just interpolate numeric values or can perform complex tweening, such as finding intermediate data between one matrix or polygon and another. For further information, see Chapter 26, "Tween Components and Native Tween Types."