By now, I'm sure that you've all heard about QuickTime, Apple's multimedia extension to the Mac's system software. I personally have had trouble internalizing what QuickTime will mean to the normal Macintosh user. With an eye to correcting that, I jumped at a chance to talk to Joseph Ansanelli, QuickTime product manager at Apple. He sent me an overview of what QuickTime provides and answered a bunch of my questions and concerns about QuickTime. This article is based entirely on his overview and the talk we had.
Apple hopes to broaden the scope of the Macintosh through QuickTime. When the Mac first appeared, its use of integrated graphics set it apart from its character-based brethren. Although the Mac has always had decent sound capabilities, sound, animation, and video were all hacks that were limited to specialized programs. QuickTime will release these three methods of communication (this is probably the point where I should include a pithy quote from Marshall McLuhan, but I'll refrain this time) into the Macintosh world at large, integrating them tightly with Macintosh hardware and all Macintosh software. Why do you think Apple starting including a microphone on some new Mac models? Because Apple is building QuickTime into future versions of the system software and because QuickTime runs on all Macs that use the 68020 or later with 2 MB of RAM, it will become a common development point, much as cut, copy, and paste of PICTs is now. In addition, QuickTime is modular, so you can install newer and snazzier "components," as Apple calls them, at any time. Finally, Apple is making the QuickTime Movie file format open so it can migrate to other platforms.
Enough of the theory and on to the details! QuickTime has four main parts, the system software, the file formats, the Apple compressors, and the human interface. The system software part of QuickTime is composed of the Movie Toolbox, which aids in the creation, editing, and playback of movies (I'll get to the definition of a movie in a bit), the Image Compression Manager, which arbitrates between applications and the compression components, and the Component Manager, which acts as an intermediary between applications and external devices, such as digitizer cards or VCRs. Applications work with the Movie Toolbox so they can incorporate support for the movies. Apple claims that developers have been able to support movie playback in two to three days. The Image Compression Manager handles compression requests from applications and matches them with the most appropriate compression module installed in the system. It will also handle picky little details like clipping, scaling, crossing screens, and fast dithering (which lets you view a 24-bit movie in a lower resolution at the same speed). The Component Manager works slightly like the Image Compression Manager in that it mediates between applications and components (modules) that developers write to drive their hardware. Essentially, the Component Manager does for many devices what Apple's printing architecture did for printers. You have one driver for each printer, and all applications work through that driver. In contrast, DOS applications require a driver for each piece of hardware in each application, so both Word and WordPerfect have hundreds of printer drivers for the same printers, but you can't use Word's drivers in WordPerfect or vice versa. The Component Manager actually works with all external resources, which includes system extensions, so it can handle software as well as hardware.
QuickTime includes two new file formats, extensions to the PICT format and the Movie format (moov for those of you who pay attention to the file types - it can also be pronounced with a bad accent to get "moof" - wonder where that might have come from :-)). Apple extended the PICT format by adding support for compression using any compression scheme registered with the Component Manager and by adding preview support. The preview will consist of a 4-5K thumbnail image saved with the PICT. Archiving applications could use that image, and Apple plans to support it in the extended Standard File (SF) Dialog box when you are opening PICTs. The Movie format is much more ambitious. It is a container for multiple types of dynamic data, such as sound and video, which will be the first two tracks (types of information included in the Movie format) defined by Apple. QuickTime will handle synchronization of the tracks, and it stores the description of the data separate from the data itself, which (although I don't have a complete grasp on why yet) allows for multiple versions of the data without duplicating the content each time. Like the new PICT, the Movie format will include preview support, but in two forms, posters and previews. Posters (as you would expect) are still frames which represent the movie for printing, whereas previews (as you would also expect) are short clips that represent the whole when previewing in an SF Dialog box, for instance. One feature of QuickTime that no doubt helped attract IBM is its openness and extensibility. Apple encourages third parties to use the Movie format as a cross-platform medium of exchange. Apple also plans to extend the number of tracks in the Movie format past the original two. An obvious choice for a new track type is a MIDI track, but I suspect people will think of plenty more types in the coming years. To integrate the Movie format with the rest of the Mac, Apple has ensured that it will have full Clipboard and Scrapbook support, so people will be able to cut, copy, and paste movies to their hearts' content. Joe said that he expected 50 to 100 applications to support the Movie file format by the beginning of 1992, which indicates that developers are taking QuickTime seriously.
As far as the Apple Compressors go, Apple has three basic ones to start with, the Photo Compressor, the Animation Compressor, and the Video Compressor. The Photo Compressor is an implementation of the JPEG (Joint Photographic Experts Group) standard and can compress images between 10 and 25 times with no visible image degradation. If you want an example of JPEG compression, check out the color image we sent to sumex-aim.stanford.edu along with a free JPEG decompressor (in the same file). The Animation Compressor can decompress and display animations on the lower-end Macs without speed degradation using both lossless and lossy modes of compression. The compression ratios vary widely, depending on what is included in the animation. Finally the Video Compressor can decompress video sequences from a hard disk or, more impressively, a CD-ROM in real time with no extra hardware. It too can compress files between five and 25 times. All of these compressors are optimized for speed as well, and from what I've heard, you don't really notice any additional processing going on while the file decompresses. One thing that worried me slightly at first was the role of the popular compression programs in all of this. Joe assured me that while it was certainly possible to write a DiskDoubler component for QuickTime, it would only work with QuickTime-compatible applications, and everyone would have to have that component. So while Salient or Aladdin could come up with a QuickTime compression component, it will be unlikely to hurt the rest of their market.
The last part of QuickTime is the Human Interface. Apple has defined two new interfaces to work with QuickTime. First, the SF Dialog will support preview of PICTs and movies, which will be handy, and second, Apple has a control mechanism for viewing movies. It includes gadgets that look much like the standard window gadgets, but are located at the bottom of the window. You can toggle the sound, play or stop the movie, and step forward or backward through the movie. In addition, the largest control is a slider bar much like the standard elevator bar, with which you can jump around within the movie and get a sense of your location in the movie. This sort of interface standardization is what has set Apple apart from other companies, and is what will continue to do so in the future unless the competition takes note.
Developers can get an APDA toolkit for QuickTime that includes the QuickTime Extension, picture and movie utilities, XCMDs for HyperCard, and sample code and drivers. The toolkit comes on a CD-ROM and costs whatever a normal toolkit from APDA does. If you as an end user want to check out QuickTime, Apple will have a QuickTime sampler floppy that will contain the QuickTime Extension, various pictures, movies, and conversion utilities, and some samples. The disk will be free and will be distributed through user groups, bulletin boards, and dealers.
One of the things I've been trying to think about since I talked to Joe is what sorts of applications lend themselves to working with QuickTime. The best candidates I've thought of (and the most obvious, certainly) are interactive help and training systems and dynamic Post-It-type notes (which some applications already have, but without the benefit of standardization). If you think back a few weeks to the article I did on videoconferencing, QuickTime should be able to do everything I said about animating a talking head and synchronizing a voice with the mouth movements, all in real time with full compression. I'd hope to see that sort of application come from a company like Farallon fairly quickly.
QuickTime's main competition will come from the MPC (Multimedia PC) group that Microsoft started but which is now an independent organization. MPC must approve a computer for it to carry the MPC label, indicating that it has certain hardware capabilities and peripherals. The low end of the MPC line is a 286 with VGA graphics. Also commonly included (if not required, I'm unsure about this) are a CD-ROM player and audio hardware. Microsoft plans to come up with multimedia extensions for Windows which will cover much of what Apple has done with QuickTime, although from the sounds of it, Microsoft's extensions for Windows aren't as comprehensive or as well thought out as QuickTime. In addition, because of the overhead with Windows sitting on top of DOS, even a fast MPC-approved PC won't be faster than cheaper Macs that have inherent QuickTime support. I've heard from someone who saw a 25 MHz 486 doing enhanced JPEG compression that the PC was only about as fast as a Mac LC doing the same compression under QuickTime. MPC-approved machines can be 286's, but most will probably be 386's, simply because the 286 is slow and more or less obsolete. From what I've heard, MPC merely raises the multimedia level of the standard PC to what the Mac had about three years ago. Also keep in mind that QuickTime will be free at first and then will be integrated into Apple's free system software and bundled hardware (such as the Mac's sound chip and microphone), unlike Windows and the standard PC.
QuickTime actually works now with all programs, thanks to a quick extension hack by Apple France that fools all applications into being QuickTime compatible. I gather it has some bugs, not surprisingly, but is otherwise quite useful. Interestingly enough, and I'm not sure of the form this takes, the application Apple apparently uses to demo QuickTime is a beta version of the next release of WordPerfect, so it sounds like major developers are jumping right into the QuickTime boat. Apple has shown QuickTime at the Interactive Multimedia Association and is pushing it as a cross-platform standard format for dynamic data. There's no reason the movie format can't be used by Macs, PCs, Suns, NeXTs, etc., and if nothing else, I think it is one of the first proposed comprehensive standards in this field. Interesting stuff, so keep your eyes on QuickTime when Apple finally ships it by the end of 1991. I'm certainly not one to jump on the Multimedia-Will-Save-The-Industry-Bandwagon, but I do think QuickTime will stimulate creative thought that hasn't been too prevalent recently.
Joe Ansanelli -- firstname.lastname@example.org
MacWEEK -- 21-May-91, Vol. 5, #20, pg. 6
MacWEEK -- 16-May-91, Vol. 5, #19, pg. 6
InfoWorld -- 10-Jun-91, Vol 13, #23, pg. 45
PC WEEK -- 10-Jun-91, Vol 8, #23, pg. 8