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Locating Tracks, Saving Movies, and Modifying Movie Properties

The Movie Toolbox provides a set of functions that help your application locate a movie’s tracks and media structures. This chapter describes these functions and how to use them. In addition, the chapter discusses functions you can use to save movies, capture and restore the edit state of a movie, and modify movie properties. A later section of the chapter discusses support for progressive downloads.

The Movie Toolbox identifies a movie’s tracks in two ways. First, every track in a movie has a unique ID value. This ID value is unique throughout the life of a movie, even after it has been saved. That is, no two tracks of a movie ever have the same ID, and no ID value is ever reused. Second, a movie’s current tracks may be identified by their index value. Index values always range from 1 to the number of tracks in the movie. Track indexes provide a convenient way to access each track of a movie.

There are several functions that allow you to find a movie’s tracks. You can use the GetMovieTrackCount function to determine the number of tracks in a movie. Use the GetMovieTrack function to obtain the track identifier for a specific track, given its ID. The GetMovieIndTrack function lets you obtain a track’s identifier, given its track index.

You can obtain a track’s ID value given its track identifier by calling the GetTrackID function.

You can determine the movie that contains a track by calling the GetTrackMovie function.

The GetTrackMedia function enables you to find a track’s media. Conversely, you can find the track that uses a media by calling the GetMediaTrack function.

Contents:

Saving Movies
Time Base Callback Functions
Creating and Disposing of Time Bases
Working with Movie Time
Working With Movie User Data
The Time Structure
The Fixed-Point and Fixed-Rectangle Structures
Media Handler Support
Data Handler Components
Support for Progressive Downloads
Displaying a Progressively Downloaded Movie
Handling Media Sample References
Manipulating Media Input Maps

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