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Media Data Atom Types

QuickTime uses atoms of different types to store different types of media data—video media atoms for video data, sound media atoms for audio data, and so on. This chapter discusses in detail each of these different media data atom types.

If you are a QuickTime application or tool developer, you’ll want to read this chapter in order to understand the fundamentals of how QuickTime uses atoms for storage of different media data. For the latest updates and postings, be sure to see Apple's QuickTime developer website.

This chapter is divided into the following major sections:

• “Video Media” describes video media, which is used to store compressed and uncompressed image data in QuickTime movies.

• “Sound Media” discusses sound media used to store compressed and uncompressed audio data in QuickTime movies.

• “Timecode Media” describes time code media used to store time code data in QuickTime movies.

• “Text Media” discusses text media used to store text data in QuickTime movies.

• “Music Media” discusses music media used to store note-based audio data, such as MIDI data, in QuickTime movies.

• “MPEG-1 Media” discusses MPEG-1 media used to store MPEG-1 video and MPEG-1 multiplexed audio/video streams in QuickTime movies.

• “Sprite Media” discusses sprite media used to store character-based animation data in QuickTime movies.

• “Tween Media” discusses tween media used to store pairs of values to be interpolated between in QuickTime movies.

• “Modifier Tracks” discusses the capabilities of modifier tracks.

• “Track References” describes a feature of QuickTime that allows you to relate a movie’s tracks to one another.

• “3D Media” discusses briefly how QuickTime movies store 3D image data in a base media.

• “Hint Media” describes the additions to the QuickTime file format for streaming QuickTime movies over the Internet.

• “VR Media” describes the QuickTime VR world and node information atom containers, as well as cubic panoramas, which are new to QuickTime VR 3.0.

• “Movie Media” discusses movie media which is used to encapsulate embedded movies within QuickTime movies.

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