QuickTime
From Wikipedia, the free encyclopedia.
| QuickTime | |
|---|---|
 QuickTime 7 Player under Mac OS X |
|
| Maintainer: | Apple Computer |
| Stable release: | 7.0.3 (October 12, 2005) [+/-] |
| Preview release: | none (?) [+/-] |
| OS: | Mac OS X, Windows 2000 or later |
| Genre: | Media player |
| License: | Proprietary |
| Website: | www.apple.com/quicktime/ |
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.
The most recent version is 7.0.3 and is available for the Macintosh and Windows platforms.
Contents |
Overview
The QuickTime technology has three major components:
- the QuickTime file format itself — openly documented and available for anyone to use royalty-free
- a media player which Apple makes available for free download on its website and bundles with each of its computers
- software development kits available for the Macintosh and Windows platforms. These kits allow people to develop their own software to manipulate QuickTime and other media files
History
Apple released the first version of QuickTime on December 2, 1991 as a multimedia add-on for System 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 TV commercial on a Mac, at the time an astounding technological breakthrough. Microsoft's competing technology — Video for Windows — did not appear until November 1992.
That first version of QuickTime laid down the basic architecture which survives essentially unchanged today, including multiple movie tracks, extensible media type support, an open-ended file format, and a full complement of editing functions. The original video codecs included:
- the Apple Video codec (also known as "Road Pizza"), suited to normal live-action video
- the Animation codec, which used simple run-length encoding and better suited cartoon-type images with large areas of flat color
- the Graphics codec, optimized for 8-bit-per-pixel images, including ones which had undergone dithering
Apple released QuickTime 1.5 for Mac OS in the latter part of 1992. This added the SuperMac-developed Cinepak vector-quantization video codec (initially known as Compact Video), which managed the unheard-of feat of playing back video at 320*240 resolution at 30 frames per second on a 25MHz 68040 CPU. It also added text tracks, which allowed for things like captioning, lyrics etc at very little addition to the size of a movie.
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. Version 1.0 of QuickTime for Windows provided only a subset of the full QuickTime API, including only movie-playback functions driven through the standard movie controller.
QuickTime 1.6.x came out the following year. Version 1.6.2 first incorporated the "QuickTime PowerPlug" which replaced some components with PowerPC-native code when running on PowerPC Macs.
Apple released QuickTime 2.0 for Mac OS in February 1994 — the only version never released for free. It added support for music tracks, which contained the equivalent of MIDI data and which could drive a sound-synthesis engine built into QuickTime itself (using sounds licensed from Roland), or any external MIDI-compatible hardware, thereby producing sounds using only small amounts of movie data.
The next versions, 2.1 and 2.5, reverted to the previous model of giving QuickTime away for free. They improved the music support and added sprite tracks which allowed the creation of complex animations with the addition of little more than the static sprite images to the size of the movie.
QuickTime 2.0 for Windows appeared in November 1994.
The release of QuickTime 3.0 for Mac OS on March 30, 1998 introduced the now-standard revenue model of releasing the software for free, but with additional features of the Apple-provided QuickTime Player and Picture Viewer applications that end-users could only unlock by buying a QuickTime Pro license code.
QuickTime 3.0 added support for graphics importer components that could read images from GIF, JPEG, TIFF and other file formats, and video output components which served primarily to export movie data via FireWire. It also added video effects which programmers could apply in real-time to video tracks. Some of these effects would even respond to mouse clicks by the user, as part of the new movie interaction support.
Apple released QuickTime 4.0 for Mac OS on June 8, 1999. This added graphics exporter components which could write some of the same formats that the previously-introduced importers could read, though interestingly not GIF (possibly because of the LZW patent). It added the second version of the Sorenson video codec, and support for streaming.
QuickTime 4.1, released at the beginning of 2000, added support for movie files larger than 2 gigabytes on Mac OS 9 and later; and dropped support for 68K Macs. Users gained the ability to control the QuickTime Player via AppleScript.
QuickTime 5.0 for Mac OS appeared on April 23, 2001. It added "skins" to the QuickTime Player and multiprocessor image compression support. The other notable addition was the controversial move of making full screen video modes only available to QuickTime Pro license holders, a state of affairs that remains to this day. Four years later, on May 9, 2005, Apple released iTunes 4.8 with support for viewing full screen QuickTime video, through iTunes.
QuickTime 6.0 for Mac OS, released on July 15, 2002, first included a version for Mac OS X.
| 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 |
| January 14, 2003 | QuickTime 6.1 | Mac OS X | "Quality and performance enhancements" |
| March 31, 2003 | QuickTime 6.1 | Windows | Fix for CAN-2003-0168 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 | 3GPP and AMR |
| October 16, 2003 | QuickTime 6.4 | Mac OS X, Windows | Pixlet codec, integrated 3GPP |
| December 18, 2003 | QuickTime 6.5 | Mac OS X, Windows | 3GPP2 and AMC mobile multimedia formats |
| April 28, 2004 | QuickTime 6.5.1 | Mac OS X, Windows | Apple Lossless |
| October 27, 2004 | QuickTime 6.5.2 | Mac OS X, Windows | Bug fixes, security updates and quality and performance enhancements |
| October 12, 2005 | QuickTime 6.5.3 | Mac OS X v10.2.8 | |
QuickTime 7 was released on April 29, 2005 with Mac OS X v10.4 featuring complete MPEG-4 compliance, H.264/MPEG-4 AVC codec, live resizing, multi-channel audio, full-screen overlay, and full support for interactive animations created with Apple's new tool Quartz Composer. Version 7 was also released for 10.3.9.
On June 6, Apple issued a preview release of QuickTime 7.0 for Windows 2000 and Windows XP. This was followed by "Public Preview 2" on July 13, "Public Preview 3" on August 14 and the first non-preview release on September 7, 2005.
| Updates to QuickTime 7 | |||
|---|---|---|---|
| Release Date | Version | Platforms | Features |
| May 31, 2005 | QuickTime 7.0.1 | Mac OS X | Fix a security issue with the Quartz Composer plugin |
| July 15, 2005 | QuickTime 7.0.2 | Mac OS X | Bug fixes and compatibility enhancements |
| September 7, 2005 | QuickTime 7.0.2 | Windows 2000/XP | First non-preview release |
| October 12, 2005 | QuickTime 7.0.3 | Mac OS X Windows 2000/XP | Streaming and H.264 bug fixes. Needed to support video purchases through iTunes Music Store. |
| October 29, 2005 | QuickTime 7.0.3.50 | Windows 2000/XP | |
QuickTime file format
A QuickTime file functions as a multimedia container file that contains one or more tracks, each of which store a particular type of data, such as audio, video, effects, or text (for subtitles, for example). Each track in turn contains track media, either the digitally encoded media stream (using a specific codec such as Cinepak, Sorenson codec, MP3, JPEG, DivX, or PNG) or a data reference 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 to use.
Internally, QuickTime files maintain this format 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.
Apple's plans for HyperCard 3.0 illustrate the versatility of QuickTime's file format. The designers of Hypercard 3.0 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.
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 formats such as AIFF DV, MP3, MPEG-1, and AVI. Other later-developed media container formats such as Microsoft's Advanced Streaming Format or the open source Ogg and Matroska containers lack this abstraction, and require all media data to be rewritten after editing.
QuickTime and MPEG-4
On February 11, 1998 the ISO approved the QuickTime file format as the basis of the MPEG-4 *.mp4 container standard. Supporters of the move noted that QuickTime provided 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 does not mesh well with editing). Developers added MPEG-4 compatibility 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 would constrain many users and content providers. Following a compromise, Apple released QuickTime 6 on 15 July 2002.
QuickTime players
Apple releases official media player software for Mac OS and Windows for free under the brand QuickTime Player. (Earlier versions simply used the name "MoviePlayer.") The player also comes with a number of media-editing and media-creation features, but users have to unlock these by purchasing a key from Apple, turning the media player into QuickTime Pro.
A number of companies utilise QuickTime for their software, for example:
- Apple's own iTunes jukebox audio player (designed for easy manipulation of audio media) utilises QuickTime for its playback technology
- copies of the Encyclopædia Britannica on DVD require QuickTime to play movie clips
- iScreensaver Designer makes screensaver installers for Mac OS 8.6 through OS X and Windows 98 through XP, and builds from either platform to the other, demonstrating QuickTime's cross-platform versatility and stability
- Many other software installation compact discs include QuickTime
Independent players for QuickTime 6 (MPEG-4) exist for many operating systems, and the FFmpeg library even supports the Sorenson video compression format, as well as the Q Design audio codec often used alongside it. Apple, however, has licensed Sorenson technology exclusively.
QuickTime Alternative, as the name implies, uses specific QuickTime libraries and an alternative media player to avoid a full QuickTime installation.
QuickTime Pro
QuickTime Pro is a paid‐for version of Apple Computer's free QuickTime media player technology. It provides features, such as full-screen playback, MPEG-4 (and H.264 in version 7) creation (see below) and other features not available in the free player, such as exporting to a wide variety of different video codecs (such as Animation, DV, mjpeg, etc.), still graphic formats (TIFF, PICT, JPEG), and Audio (WAV, AIFF). The Pro features resp. their limitation in the free version apply to the QuickTime Player application only. Other software that uses the QuickTime framework can use the save/export features without the need for the license, e.g. some video editing packages that rely on QuickTime for their export/import abilities do so by using the QuickTime framework, no matter if a Pro key is present or not. Another example would be iTunes and its audio encoders that do not require the Pro license to work.
QuickTime development
Developers can use the QuickTime software development kit to develop multimedia applications for Mac or Windows with the C programming language or with the Java programming language.
QuickTime consists of two major subsystems: the Movie Toolbox and the Image Compression Manager. The Movie Toolbox consists of 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.
QuickTime 7.0 introduced the QuickTime Kit (aka QTKit), a developer framework that is intended to replace previous APIs for Cocoa developers.
QuickTime 7 Pro now offers support to export video files encoded in H.264 at 320x240 pixels to be viewed on the new fifth generation iPod.
