11.2. Beatnik authoring system
The Beatnik authoring system includes three elements: the Beatnik Player, the Beatnik Audio Engine, and the Beatnik Editor. All three work in conjunction to mix and play back music and sound effects that are composed of a hybrid of MIDI-based instrument sounds and web-optimized digitized audio samples.
MIDI forms the core of the Beatnik System. Beatnik uses MIDI-like messages to control the Beatnik playback sound engine. Other authoring systems such as Flash must compile and upload MP3-compressed sound files for playback in a browser. In addition to compressed MP3 audio files, Beatnik compiles and uploads text-based MIDI instructions that trigger the pre-loaded bank of Beatnik MIDI instrument sounds to play back your musical score or composition. Once these standard instruments are downloaded with the Beatnik Player and housed on a user's hard drive, little data needs to be sent over the Internet -- just tiny instructions (compressed MIDI files) that instruct the Beaknik Player's tone generator/sequencer to play music. Later in this chapter, we will discuss the Beatnik Player's components in more detail.
Even though it relies on MIDI, the Beatnik System should not be confused with basic MIDI music on the Web. When a MIDI file is downloaded, it plays back using the General MIDI instrument bank pre-installed on most browsers and computer systems. General MIDI is a standard established by music equipment manufacturers that specifies that a given instrument bank number always represents a certain type of instrument sound, such as a horn or a drum. However, manufacturers are free to determine the synthesis algorithm used to create any given sound in their instrument bank. This leads to two problems: every instrument bank can have a different type of horn or drum sound, and there is no way to alter or customize the sounds in the instrument bank.
In addition to the General MIDI instrument bank, Beatnik allows you to customize and enrich its palette of high-quality, pre-installed sounds with your own digital audio samples. Once your custom audio samples and MIDI files are imported into the Beatnik Editor, the editor compresses everything into the proprietary Beatnik format for embedding into your web pages. The result is a General MIDI sound engine combined with a customizable digital audio sampler.
Mixman remixers are another compelling use of Beatnik technology. By clicking on different buttons, users can remix popular songs, such as "Maria" by Blondie and email their mixes to friends. The Mixman remixers itself is a multichannel .rmf composition and is typically only 250 KB in size. Smaller still is the emailed remix data, which is simply the instructions dictating which channels to play or mute. The .rmf file is not actually emailed, but instead is served from a central location. An example of a Mixman remixer is shown in Figure 11-2.
Beatnik sound banks also provide Groovoids, a set of musical snippets or compositions. Groovoids are premade miniature MIDI compositions or sound effects used for quickly and easily creating loops, button sounds, and transition effects. Later in this chapter, we will walk through the steps involved in creating Beatnik files and publishing them to a web page.
Figure 11-2. By clicking on different buttons, users can remix popular songs, such as "Maria" by Blondie, and email their new "mix" to friends.
11.2.1. Beatnik Player
At the heart of the Beatnik System is the Beatnik Player, a browser plug-in that users must install. It's free, and it's a fairly small download (about 550 KB). Beatnik is working to have it included with other browsers, including Navigator and Internet Explorer.
The plug-in player allows the user's browser to play .rmf files (Beatnik's Rich Music File format). The Player also contains a software-based tone generator with two banks of 128 instruments each and a third bank for customized audio samples. The first of these banks comprises a standardized library of Beatnik instruments that map to the General MIDI specification. The second bank is a library of special Beatnik instruments. There is also a library of General MIDI percussion instruments and a library of special percussion instruments, which are assigned to MIDI channel 10 (the General MIDI drum channel). The third bank is empty and is used for receiving and storing any customized instruments contained within a given .rmf file. This user-definable bank of instruments allows sound designers to create custom instruments based on their own digital audio samples (or edited versions of the standard Beatnik library).
Although most designers will opt to keep the Beatnik player invisible to the end user, there are visible modes as well, which can be useful to provide end-user control. The visible Beatnik player features standard play, stop, and pause buttons, and more. You can toggle between the "meter" and "oscilloscope" visual modes by simply clicking on the lower part of the Control Player window. See Figures Figure 11-3 and Figure 11-4.
Figure 11-3. The Beatnik Player Control Panel's Meter mode displays flashing meters that show which of Beatnik's 32 voices are active.
Figure 11-4. Clicking on the lower part of the Beatnik Player's Control Panel displays the oscilloscope mode, which monitors Beatnik's total audio output.
These two different modes provide alternate visual representations of a sound's playback. The meter mode displays a visual representation of the active channels producing sound. The oscilloscope mode displays a line that changes according to the different frequencies being played back.
Clicking and holding (Macintosh) or right-clicking (Windows) the mouse button brings up a series of commands that allows the user to perform other actions, such as pause or stop, display song, and show copyright info and other relevant media information.
11.2.2. Beatnik Audio Engine
11.2.3. Beatnik Editor
The Beatnik Editor is the tool used for creating .rmf files. Unlike full-featured MIDI sequencers with multitrack editing and recording capabilities, the Beatnik Editor is primarily a content integration tool for combining MIDI scores with custom digital audio samples. The editor lets you import MIDI files from your favorite MIDI sequencing program and map the various MIDI tracks to the desired Beatnik instruments. The Beatnik Editor also allows you to input your own sampled recordings, such as a three-second vocal line or a guitar riff, and map it to the MIDI note ranges of your choosing. The editor accomplishes this by creating a third bank of sounds that resides in the .rmf file itself and is served to the user's browser along with the .rmf file. The process is similar to working with a MIDI keyboard sampler to create custom patches. The Beatnik Editor audio samples can be musical instrument sounds, sound effects, or even short vocal samples.
It is important to note, however, that unlike the standard Beatnik instruments that reside on the user's computer (in the first two banks of the Beatnik Player), these custom instrument samples must be downloaded with the .rmf file over the Internet. So if you are using custom sounds, you will want to compress your audio samples using the Beatnik Editor's MP3 compression. The Beatnik Editor even allows you to mix and match variable encoding rates, sample rates, and bit depth, all in the same .rmf file. This allows you to "crunch" the file size of some sounds while allowing more fidelity (and file size) to more delicate sonic textures.
With these three elements of the Beatnik System, you can create customized, complex, responsive musical interaction with the graphical elements of your web site. You also can achieve extremely small file sizes if you are careful to crunch down your custom instrument sounds. And you have the tools to control all aspects of a sound's quality. Now let's get into the specific process of authoring with Beatnik tools.
11.2.4. Authoring with Beatnik
11.2.5. Introduction to the Music Object
To begin authoring with the Music Object, follow these steps:
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