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Desktop Video AGOCG Report

Apple QuickTime

QuickTime is an extension to the Mac's system software which provides system-level support for dynamic media types, such as video animation and sound. Its most obvious and appealing feature is the ability to use a Mac to play video clips, but there is more to QuickTime than that. The real aim of QuickTime is compatibility between hardware and software. QuickTime provides a series of ways for any software package to address and use specialist video hardware, such as a video capture board. With QuickTime the user can employ a standard editing package like Adobe Premiere with a video capture card, from a budget priced 400 VideoSpigot to 5000 cards designed for professional quality video production on the Mac.

QuickTime is a set of protocols that allow a Mac or a PC running Windows (or any other computer in the future, hopefully) to use a single interface to create/display/manipulate movies that contain digitised video, sound, text, etc. The standard output is a QuickTime "Movie" that can be a file or one of several different formats. An important aspect is that the user has no need to know what is in the file or what format it is.

What makes QuickTime so special (and therefore arguably better than most other solutions) is that (a) it keeps the video and sound in sync on any machine, (b) in theory it runs at the same speed on all machines,1 and (c) it is to some extent hardware independent, meaning it can run on any Mac from the Plus to the Quadra 840AV or any PC using Windows and will run to the best of its ability on those machines.

However, the real power behind QuickTime is the ability of so many applications to work with the same files in exactly the same way as well as the ability for QuickTime to be upgraded at any time by any company. Apple ships QuickTime with a certain set of compressors. In the future, other companies will be able to ship additional compressors (either free or licensed with software) that will be made available via QuickTime to every single program that accesses QuickTime.

For example, a 10 fps 160 x 120 movie will run well on an LC machine and better, but on a Quadra 840AV it is possible to run a 15 fps 320 x 240 movie; with an extra video board, or potentially with a PowerPC, 30 fps full-screen video is possible. Add to this the fact that it runs under Windows as well, while Video for Windows does not run on Macs, and it is an attractive prospect.

QuickTime is the Apple system for handling the multimedia concept and differs from Video for Windows in that it is a standard architecture for linking video, audio and animation along with other dynamic data types into applications. It gives users a standard way to display, copy, paste and compress time-based data, which makes it easy for anyone to create multimedia documents.

QuickTime is composed of three major components: the Movie Toolbox, the Image Compression Manager and the Component Manager. The Movie Toolbox provides routines that allow applications to control all aspects of movies in Macintosh applications. There are Movie Toolbox routines that provide basic operations for opening and playing movies as well as more complex routines for the creation and manipulation of the data that make up the movie's media.

The Image Compression Manager (ICM) provides applications with image compression and decompression services that are device and algorithm independent. As with Video for Windows, the algorithms are designed as plug in CODECs and QuickTime can use them to read and perform compression `on the fly'. The ICM also manages display details such as clipping, crossing screens, scaling and fast dithering and provides a common compression interface for all compatible software.

The last main part of QuickTime is the Component Manager, which allows external resources such as digitisers, VCRs and accelerator cards to register their capabilities with the system at run time. Once registered they can be made available to all compatible applications, without the programmer having to know which devices the user may have available.

Just as Video for Windows uses the Media Player as a standard interface for viewing AVI clips, QuickTime has a standard `human' interface for dealing with movies. Apple's is similar to Microsoft's in appearance, with controls for playing, stopping, fast forwarding and rewinding data, but the QuickTime controller features a sliding volume control.

In mid December 1993, Apple began to demonstrate a further advance in video technology. This was the integration of MPEG into applications using QuickTime. Apple announced that MPEG would become the digital video standard for compact disks, cable TV, direct satellite broadcast and High Definition TV (HDTV). Future devices which use MPEG technology with QuickTime will become more powerful. MPEG by itself only allows playback. With the addition of QuickTime, devices that use MPEG will additionally be able to edit, search for and interact with video information. In a related announcement, Apple stated that Fujitsu had joined (among others) Silicon Graphics and KALEIDA, in adopting the QuickTime standard. QuickTime for Windows is available for customers who use Microsoft's Windows/DOS operating system.

At the Tokyo Multimedia conference, Apple publicly demonstrated the Apple Media Kit for the first time. This is based on QuickTime and is a digital publishing tool facilitating the creation of multimedia titles to multiple platforms.

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