Movie Toolbox: Data Types

This chapter describes the constants and data types used by the Movie Toolbox. This includes the four-character media type constants, flags used with Movie Toolbox functions, and data structures such as movie identifiers, the time structure, fixed-rectangle structures, and the sound description structure.

This chapter also covers the topic of QuickTime atoms in detail. This material will be of interest to most QuickTime developers.

New Constants

QuickTime 3 Reference lists the constants that were added to QuickTime after release 1.6. Most of the constants are used as flags for QuickTime functions, and allow the programmer to pass numeric data as a meaningful name.

Data Types

Inside Macintosh describes the data types defined for QuickTime and used by your application when interacting with the Movie Toolbox. Constants used to communicate with Movie Toolbox functions are also defined. QuickTime 3 Reference describes the new data types added to QuickTime after version 1.6 (up to version 3.0). This information will be of interest to most QuickTime developers. Those already familiar with QuickTime will be primarily interested in the data types listed as "New."

New:

Original:

Creating and Modifying QT Atom Containers

QuickTime 3 Reference describes the functions used to create, dispose of, read from, and store to QuickTime Atom Containers. The QT Atom is an enhancement of the existing Atom data structure. Most QuickTime data structures (movies, tracks, media) are built of Atoms. Newer QuickTime data structures (timecode tracks, sprites) are implemented using QT Atoms. The concept of the QuickTime Atom is more fully discussed in the chapter " Movie Toolbox: New Features ." The concept of Atoms is discussed in the chapter [HandLink] "QuickTime File Format."

Retrieving Atoms and Atom Data

QuickTime 3 Reference describes the functions used to retrieve QT Atoms and atom data. Each QT Atom contains either data or other atoms.