Interactive Web Music

Oct 1, 1999 12:00 PM, Scott R. Garrigus

Although the Internet's uses for business and entertainment are expanding daily, the essential format remains largely unchanged: text and graphics continue to make up most of the available content. And though most Web sites are still silent, a growing number of companies are recognizing the benefits that sound and music add as an enhancement to the browsing experience.

This development opens the door to new opportunities for the modern musician. If you can create bandwidth-friendly MIDI and audio files, you may be able to supplement your income with online gigs. However, before you get too excited about the prospect of making big bucks by composing for the Web, you should know that Internet music production is no longer simply a matter of creating General MIDI files or streaming audio for background playback. These days the buzz is all about interactive music.

WHAT'S INTERACTIVE MUSIC? Interactive music combines computer programming and musical composition to create a virtual environment in which the music content is influenced by external stimuli. So instead of being "set in stone" like, say, a movie soundtrack, interactive music changes based on input from the listener. In its simplest form, interactive music can be thought of as the triggering of sounds or musical passages by a user's actions. In a video game, for example, the player might click on an object to make his or her character stronger; this action could then trigger a distinctive "power-up" sound or musical sequence to let the player know that the character has indeed gained strength. Clicking on a different type of object could trigger a different sound to identify that object, and so on. At a Web site, for example, a user might click an onscreen button or text link, which could then trigger a sound to indicate that the action was successful.

Truly interactive music, however, not only responds to simple user actions but also takes into account what's happening in the environment at the time the action takes place. In a video game, the player may have to guide a character through a particular environment, such as a long hall in a castle. Initially, the hall might be empty, and a basic musical theme for the game would play in the background. If an enemy character suddenly appears, however, the background music could change to reflect the suspenseful situation.

As a Web-related example, a travel agency site might have a generic musical theme playing in the background on its home page. Listed on the page would be links to information on a number of vacation destinations, such as Hawaii. Moving the cursor over the Hawaii link would make the background music change to a relaxing Hawaiian tune; dragging the cursor off the link would bring back the original theme.

WHAT'S AVAILABLE? Unfortunately, there is currently no standard format for applying interactive music to a Web site, and as far as I know only two interactive music technologies are available: Beatnik and SSEYO KoanMusic. (A third option, Microsoft's Interactive Music Control, is no longer supported by Microsoft and is officially considered obsolete.) Each technology has its strengths and weaknesses, and depending on how involved you want to get, each carries its own monetary price tag. Another drawback is that both come in the form of browser plug-ins. This means that you or your client must decide which product to use, because many Web-site visitors are reluctant to load up their computers with excess code by downloading too many plug-ins, even though they're free.

The Beatnik plug-in, from Beatnik, Inc., is the more straightforward of the two, because its most basic use is as a MIDI and audio file player. Beatnik is a General MIDI-compatible software synthesizer that can play Standard MIDI Files and a number of popular audio file formats, including WAV, AIFF, and AU. In addition, Beatnik supports MP3-encoded custom samples and loops. (For an example, check out the interactive "Fame" demonstration at www.davidbowie.com.)

The Beatnik player works on both the Macintosh and PC platforms with Netscape Navigator, Microsoft Internet Explorer, and the America Online browser. Beatnik also has its own custom file format, called Rich Music Format (RMF). An RMF file is like a "container" for Standard MIDI Files and custom audio data. RMF files can include MIDI data and up to 128 custom instruments, each consisting of up to 128 custom sounds (similar to Downloadable Samples), along with a tamper-proof copyright notice and total file protection for secure delivery over the Internet.

SSEYO's KoanMusic works a bit differently. Although it outputs MIDI data, its input doesn't come from Standard MIDI Files. Instead, it gets instructions from its own custom file formats and uses those instructions to generate music "on the fly." The process is very similar to algorithmic composition (in which you set certain parameters, and the generative engine creates music based on your settings). The KoanMusic player plug-in works on the Mac and PC with Navigator and Internet Explorer.

HOW THE TWO WORK To create interactive music with either of these interactive music technologies, you must learn some programming in either JavaScript or VBScript. These scripting languages allow you to develop computer programs that run inside an Internet browser. Because both KoanMusic and Beatnik support JavaScript as well as VBScript, and because VBScript works only with Internet Explorer, you're better off focusing on learning JavaScript. That way, you can be sure that whatever you create will run on both computer platforms and with either browser.

With Beatnik, you first create an RMF file to hold whatever MIDI and audio files you want to use in your composition. You can do this by downloading Beatnik Editor for the Mac or Beatnik Converter for the PC (see Fig. 1). At the time of this writing, Beatnik Editor was still in beta, so it's a free download. Beatnik Converter costs $34.95, although you can download a demo to try it out for 21 days. After creating your RMF file, you embed the Beatnik player into a Web page for basic playback using the following code:

To add interactivity to the playback, you must use Beatnik's special library of JavaScript "methods." The musicObject library lets you control MIDI track mute and solo, volume, program changes, and much more. And because Beatnik has a built-in software synthesizer, you can even play individual notes through JavaScript. This excerpt of code, for instance, displays a link labeled Click Me. When a visitor clicks on the link, Beatnik plays the note C2:

Click Me

You'll also find support for Beatnik scripting in Macromedia Dreamweaver and NetObjects Fusion. With these Web-authoring programs, you can create interactive music pages without learning HTML coding or JavaScript. Further, Beatnik files can be encapsulated in a Macromedia Shockwave 7.0 movie or controlled with Macromedia Flash animations for more elaborate user interfaces.

The KoanMusic player uses what SSEYO calls a KoanMix file, a collection of templates consisting of special sets of "instructions" similar to precomposed MIDI sequence loops and one-shots. The KoanMusic engine intelligently combines the templates in a KoanMix file to produce ever-evolving musical pieces that are never played exactly the same way twice. Although KoanMix files can (but do not have to) contain sequenced information, they also include rules that can allow free real-time composition as well. It is this truly generative aspect that makes KoanMusic so bandwidth friendly.

To create your own KoanMix files, you must purchase Koan Pro ($199.95) or Koan X ($29.95; see opening art). The difference between the two products is that Koan Pro lets you create your own templates; Koan X doesn't. KoanMusic has its own set of JavaScript and VBScript "methods," so you can control precisely how the music is generated. In fact, the latest KoanMusic player engine provides an even more sophisticated set of functions because it allows you to extract information from the musical process. This means that every time the music starts a new bar, for example, or every time middle C is played on MIDI channel 8, you could have a message pop up on a Web page. You can even drive Macromedia Flash and DHTML animations from a KoanMusic piece. Also, KoanMusic now supports MP3 samples on the Windows platform. (For an example, check out SSEYO's Flash-based generative VulKoan MP3mixer on its Web site. MP3 mixer is freely distributable and comes with a dance-groove sample set.)

Of course, I've only scratched the surface of what these versatile interactive music technologies can do. A detailed discussion of how to use Beatnik and KoanMusic to their fullest is beyond the scope of this article. But don't worry: further information abounds on the Internet, along with sample code and tutorials for each technology (see the sidebar "Interactive Music Resources").

BE PREPARED Most Web-site developers are just beginning to appreciate the potential for adding interactive music and sound to their pages. You can get a jump on the rest of the crowd by studying the technology now. If you're well prepared, you may be able to launch a new career as a Web maestro. And even if that doesn't happen, you may still be able to use your newfound skills in the video-gaming industry. However you look at it, interactive music is here to stay, and it's destined to grow in popularity.

Scott R. Garrigus is an author, musician, and multimedia expert. He plans to add interactive music to his Web site soon. Contact him at www.garrigus.com.

You can find all the tools and information you need to work with the Beatnik and KoanMusic players at the following Web sites:

Beatnik Home Page www.beatnik.com Download the free Beatnik player, along with demo versions of Beatnik Converter and Beatnik Editor. The full Beatnik authoring documentation is also available here.

SSEYO www.sseyo.com Download the free SSEYO KoanMusic plug-in, as well as demos of Koan Pro and Koan X Platinum. You'll also find information on using the KoanMusic technology.

Netscape's Online JavaScript Documentation developer.netscape.com/docs/manuals/communicator/jsguide4 This online book describes the core JavaScript language and its extensions for use with a Web browser.

Microsoft's VBScript Home Page msdn.microsoft.com/scripting/default.htm?/scripting/vbscript The official source of information for the VBScript language includes sample code and tutorials.