QuickTime File Format
| Filename extension |
.mov, .qt |
|---|---|
| Internet media type | |
| Type code | MooV |
| Uniform Type Identifier (UTI) | com.apple.quicktime-movie |
| Developed by | Apple Inc. |
| Type of format | Media container |
| Container for | Audio, video, text |
| Extended to | MPEG-4 Part 12 |
| Free format? | No[3] |
QuickTime File Format (QTFF) is a computer file format used natively by the QuickTime framework.[4][5][6]
Design
The format specifies a multimedia container file that contains one or more tracks, each of which stores a particular type of data: audio, video, or text (e.g. for subtitles). Each track either contains a digitally-encoded media stream (using a specific format) or a data reference to the media stream located in another file. Tracks are maintained in a hierarchical data structure consisting of objects called atoms. An atom can be a parent to other atoms or it can contain media or edit data, but it is not supposed to do both.[7]
The ability to contain abstract data references for the media data, and the separation of the media data from the media offsets and the track edit lists means that QuickTime is particularly suited for editing, as it is capable of importing and editing in place (without data copying). Other later-developed media container formats such as Microsoft's Advanced Systems Format or the Matroska and Ogg containers lack this abstraction, and require all media data to be rewritten after editing.
Relation to MP4
Because both the QuickTime and MP4 container formats can use the same MPEG-4 formats, they are mostly interchangeable in a QuickTime-only environment. MP4, being an international standard, has more support. This is especially true on hardware devices, such as the PlayStation Portable and various DVD players; on the software side, most DirectShow and Video for Windows codec packs[8][9] include an MP4 parser, but not one for QTFF.
In QuickTime Pro's MPEG-4 Export dialog, an option called "Passthrough" allows a clean export to MP4 without affecting the audio or video streams. One discrepancy ushered in by QuickTime 7 released on April 29, 2005, is that the QuickTime file format supports multichannel audio (used, for example, in the high-definition trailers on Apple's site[10]).
hfu
See also
References
- ^ "Video Media Types". IANA. 1993-06-04. Retrieved 2010-07-20.
- ^ "The Codecs Parameter for "Bucket" Media Types". IETF. November 2005. Retrieved 2010-07-20.
- ^ "QuickTime - Licensing and Trademarks - Apple Developers".
- ^ Apple Inc. "QuickTime File Format Specification: Introduction to QuickTime File Format Specification". Retrieved 2018-10-09.
- ^ AfterDawn.com. "QuickTime - AfterDawn.com glossary". Retrieved 2010-07-20.
- ^ "QuickTime container". MultimediaWiki. Retrieved 2010-07-20.
- ^ Apple Inc. "QuickTime File Format Specification: Movie Atoms". Retrieved 2018-10-09.
- ^ DefilerPak – A lightweight codec pack for Windows PCs Archived August 15, 2015, at the Wayback Machine
- ^ K-LiteCodecPack.com: Download Codecs, Videos and MP3s
- ^ Apple – Movie Trailers Archived 2010-02-13 at the Wayback Machine