QuickTime is a file format for storing and playing back movies with sound. Though developed and supported primarily by Apple Computer, this flexible format isn't limited to Macintosh operating systems. it's also commonly used in Windows systems, and other types of computing platforms. In Windows, QuickTime files usually appear with the ".MOV" filename extension.
Since 2002, Apple has started using MPEG4 video encoding on its QT streams, producing much better, if not excellent, video quality.
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.
It is currently at version 7.0.1 on the Mac platform with version 7.0.1 for the Windows platform now at a downloadable "Preview Release" stage.
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 by the open source Ogg and Matroska containers lack this abstraction, and require all media data to be rewritten after editing.
View How to convert QuickTime MOV to AVI, MPEG, WMV?
How to convert Quicktime MP4 to MPEG?
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