In its day QuickTime was bigger than Apple itself, so widely known that many who used it on their PCs weren’t even aware that it was an Apple product. As one of the first extensible frameworks for multimedia, from 1991 onwards it was at the forefront of computer audio and video. When the MPEG-4 format was standardised in 1998, it was based on QuickTime. For several years, sales of QuickTime-based products for Windows far exceeded those for Macs. Then, with the release of Catalina in October 2019, QuickTime was dead, leaving few Mac users now able to name its successor, AV Foundation (or AVFoundation, if you prefer), which had been introduced back in 2011.
QuickTime supported three main classes of media: audio, video and pictures. For each of these, its framework provided for encoding and transcoding different formats, streaming decoded content for playback, an extensive core of coder-decoder modules (codecs) which was extensible by third parties, and various types of user interaction. Together they were used for everything from playing music and MIDI to interactive games, and were widely used for movies. It also brought some of the first attempts at virtual reality with QuickTime VR, which allowed the user to navigate around VR views.
First introduced in 1991 for classic Mac OS System 6, a subset soon appeared on Windows too. With the advent of System 7 it started to flourish, and QuickTime 2.0 added features like MIDI to its original limited capabilities. MPEG-4 and AAC Audio were major enhancements in QuickTime 6.0 in 2002, which was supported on both classic Mac OS and OS X, as well as Windows.
When Apple introduced QuickTime X in 2009 for Mac OS X 10.6, features began to disappear. Most noticeable by its absence then was MIDI support. This was apparently the result of a transition to using 64-bit code, a change which was eventually to kill QuickTime completely. By this time, Apple was advancing its plans to do away altogether with 32-bit code, but a great deal of QuickTime was still firmly wedded to 32-bit. The decision was made to move to a replacement, dubbed AV Foundation, which was introduced in 2011 and finally took over from QuickTime with the release of Catalina eight years later. Despite the length of that transition period, for many users the loss of QuickTime and many 32-bit codecs was one of the biggest drawbacks of upgrading to Catalina.
AV Foundation drops still pictures (which are catered for elsewhere now) and concentrates solely on what Apple describes as “time-based audiovisual media”. Apple’s master page on AV Foundation links to a mass of documentation if you want to explore its capabilities further. If you want to understand some of the many differences between the two, Tech Note 2300 explains what’s necessary to transition QuickTime code to AV Foundation.
In many respects, AV Foundation builds on Apple’s experience with QuickTime. It may not have the same user visibility, but its replacement APIs are far more capable and include support for much of what has happened in the last decade and more since the heyday of QuickTime. At its heart is the AVAsset, a container for tracks of media such as audio, video and subtitles, a concept designed into QuickTime.
For the user, QuickTime lives on in a few places, like its Player app, although now a shadow of its former Pro version. Gone, though, are the QuickTime folders from the system, those carefully curated collections of QuickTime codecs too. If you’ve still got any QuickTime components, they’ll be legacies in your /Library folder, not that on the macOS System volume.
Apple never took a moment when Mojave handed over to Catalina to roll the credits for QuickTime: to Bruce Leak, who stole WWDC in 1991 with its first demo, Peter Hoddie, who took over from him, Paul Charlton, Michael Kellner, and a great many engineers, and all those who developed pioneering content which made QuickTime such as success. At least its sequel is proving worthy of their innovation.