Along with the rich capabilities of waveform audio and CD-DA, Windows with Multimedia supports the use of MIDI files within multimedia titles. The standard Multimedia PC platform can play MIDI files through either an internal synthesizer, or through an external synthesizer attached to the machine's MIDI port.

This capability expands your options in including sound with your titles. A variety of different MIDI files exist, from popular music soundtracks, to special audio effects. The minimal storage requirements of MIDI make it a welcome addition to your menu of audio alternatives.

This chapter introduces MIDI terms and technology, describes the characteristics of MIDI in the Multimedia PC environment, and offers some brief guidelines for authoring MIDI files for use in your titles. If you adhere to the guidelines in this chapter, the music you compose will work on all classes of Multimedia PCs—from those that only meet the base level of the specification to those that include extended MIDI capabilities.

What is MIDI?

MIDI stands for Musical Instrument Digital Interface. Established in 1982, MIDI specifies an international standard for digital music:

It specifies the cabling and hardware for connecting electronic musical instruments and computers from different manufacturers

It specifies a communications protocol for passing data from one device to another

Any musical instrument can become a MIDI device if it has a microprocessor to process MIDI messages, and includes the appropriate hardware interfaces. MIDI devices communicate with each other by sending messages through this interface. MIDI messages are actually digital descriptions of a musical score—complete with the sequence of notes, timing, and instrument designations called patches. When a set of MIDI messages is played through a music synthesizer chip, the synthesizer interprets these symbols and produces music.