QuickTime 4 For Programmers
Volume Number: 15
Issue Number: 11
Column Tag: Multimedia
by Tim Monroe, Apple Computer, Inc.
What's new in the latest version of Apple's flagship
multimedia software
QuickTime 4, the latest incarnation of Apple's digital multimedia playback and
authoring software, was released to the public in its final form earlier this summer
and, thanks to a little help from the Star Wars: Episode I craze, achieved an astounding
13 million downloads by the end of August. As you might know, George Lucas chose
QuickTime as the sole distribution medium for the Internet versions of the trailers
promoting the new Star Wars movie. Over 25 million downloads - over 450 terabytes
of data - crossed the wires in the first few months, making this the largest
Internet-related event in history.
What did the millions of people who chose the trailers encoded especially for
QuickTime 4 get? Primarily they got a better user experience, owing both to some
higher-quality video and audio codecs contained in QuickTime 4 and to an improved
user interface for the basic QuickTime movie playing application. But they also got
something they perhaps didn't realize or even care too much about at the time: the
ability to receive video and audio streamed across the Internet. Among all the various
improvements in QuickTime 4, this one stands out as the crown jewel: real-time audio
and video streaming.
This streaming capability is important for several reasons. First, it gives users the
ability to watch live events remotely. (Didn't get a seat in the hall at the latest
MacWorld conference keynote address? No problem: just fire up your computer,
connect to the Internet, and watch Apple's latest news and product announcements from
the privacy of your own workspace.) Second, and just as important, it gives users the
ability to view non-live events without downloading potentially huge files onto their
computers; this permits applications such as video-on-demand and rebroadcast
streaming.
In this article, I'll discuss some of the major innovations in QuickTime 4. I'll start by
surveying the user-level enhancements, which mainly concern the new QuickTime
Player application. Then I'll describe the important features of QuickTime's new
streaming architecture and outline what you might need to do to make your existing
QuickTime application streaming-savvy. Finally, I'll describe a few of the other
API-level additions in QuickTime 4, which allow you to manage wired actions,
multi-image files, network file transfers, and other useful tasks.