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QuickTime is a multimedia technology developed by Apple Computer, capable of handling various formats of digital video, sound, text, animation, music, and immersive virtual reality panoramic images.
There are three main components to the QuickTime technology. There is the QuickTime file format itself which is openly documented and available for anyone to use royalty-free. Apple develop a QuickTime media player which they make available for free download on their website, as well as bundle with every one of their computers. Lastly there are software development kits available for the Macintosh and Windows platforms, that allow people to develop their own software to manipulate QuickTime and other media files.
The first version of QuickTime, was released on December 2, 1991 as a multimedia add-on for Mac OS 7. The lead developer of QuickTime Bruce Leak ran the first public demonstration at the May 1991 Worldwide Developers Conference, where he played Apple's famous 1984 (television commercial) on a Mac, at the time an astounding technological breakthrough. Microsoft's competing technology Video for Windows did not appear until November 1992.
QuickTime 2.0 for Mac OS was released on February 1994.
In an effort to increase the adoption of QuickTime, Apple contracted an outside company San Francisco Canyon Company to port QuickTime to the Windows platform. The first release of QuickTime for Windows (called QuickTime 2.0 for Windows to maintain version parity with the Mac version) was released in November 1994.
QuickTime 3.0 for Mac OS was released on March 30 1998.
QuickTime 4.0 for Mac OS was released on June 8 1999.
QuickTime 5.0 for Mac OS was released on April 23 2001.
QuickTime 6.0 for Mac OS was released on July 15 2002.
The following is a list of major updates to QuickTime 6.
| Release Date | Version | Platforms | Features |
|---|---|---|---|
| July 15 2002 | QuickTime 6 | Mac OS 8-Mac OS X, Windows | MPEG-2, MPEG-4 and AAC support |
| January 14 2003 | QuickTime 6.1 | Mac OS X | "quality and performance enhancements" |
| March 31 2003 | QuickTime 6.1 | Windows | As above. Also fix for security vulnerability |
| April 29 2003 | QuickTime 6.2 | Mac OS X | Support for iTunes 4, enhanced AAC support |
| June 3 2003 | QuickTime 6.3 | Mac OS X, Windows | Support for 3GPP and AMR |
| October 16 2003 | QuickTime 6.4 | Mac OS X, Windows | Pixlet codec, integrated 3GPP support |
| December 18 2003 | QuickTime 6.5 | Mac OS X, Windows | Support for 3GPP2 and AMC mobile multimedia formats |
| April 28 2004 | QuickTime 6.5.1 | Mac OS X, Windows | Support for Apple Lossless Encoder |
QuickTime consists of two major subsystems: the Movie Toolbox and the Image Compression Manager. The Movie Toolbox is a general API for handling time-based data, while the Image Compression Manager provides services for dealing with compressed raster data as produced by video and photo codecs.
Apple releases official media player software for Mac OS and Windows for free under the brand QuickTime Player. (Earlier versions were called simply "MoviePlayer.") The player also comes with a number of media editing and creation features, however these have to be unlocked by purchasing a key from Apple, turning the media player into QuickTime Pro.
A number of companies base their software on QuickTime. Examples being, Apple's own iTunes jukebox audio player (designed for easy manipulation of audio media) which utilizes QuickTime for its playback technology or the copies of the Encyclopædia Britannica that come on DVD which require QuickTime to play movie clips.
Independent players for QuickTime 6 (MPEG-4) exist for many operating systems, and the FFmpeg library even supports the Sorenson video compression format. Apple, however, is the exclusive licensee of Sorenson technology.
A QuickTime file is a multimedia container file that contains one or more tracks that can contain a particular type of data, such as audio, video, effects, or text (e.g., for subtitles). Each track in turn contains track media, either the digitally encoded media stream (using a specific codecs such as Cinepak, Sorenson codec, MP3, JPEG, DivX, or PNG) or a pointer to the media stored in another file or elsewhere on a network. It also has an "edit list" that indicates what parts of the media are to be used.
Internally, this format is maintained as a tree-structure of "atoms," each of which uses a 4-byte OSType identifier to determine its structure. An atom can be a parent to other atoms or it can contain data, but it cannot do both.
The versatility of QuickTime's file format can probably best be illustrated by Apple's plans for HyperCard 3.0, which was originally intended to store an entire HyperCard stack (similar in structure to a complete web site, with graphics, buttons and scripts) as a QuickTime file.
This structure is similar to that supplied by the Microsoft's Advanced Streaming Format or the open source Ogg and Matroska containers. However QuickTime was the first software framework to use this format-independent framing.
In February 11 1998, the ISO approved the QuickTime file format as the basis of the MPEG-4 standard, with supporters noting that it was a good "life-cycle" format, well-suited to capture, editing, archiving, distribution, and playback (as opposed to the simple file-as-stream approach of MPEG-1 and MPEG-2, which are poorly suited to editing). MPEG-4 compatibility was added to QuickTime 6 in 2002. However, Apple delayed the release of this version for months in a dispute with the MPEG-4 licensing body, claiming that proposed license fees were prohibitive for many users and content providers. A compromise was reached, after which QuickTime 6 was released.
Developers can use the QuickTime software development kit to develop multimedia applications for Mac or Windows with the C programming language or the Java programming language.
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