How It Works
Suppose you were to listen to a music recording and enter it note by note into your sequencer. For each note being played, you would need to determine its pitch, rhythm, and dynamics, which translate to which note is being played, when and how long the note is played, and how loud it is played. IntelliScore must determine the same things. The computer starts with digital audio in the form of a wave file, MP3 file, WMA file, AAC file, AIFF file, audio CD, or live audio data. If you visually examine a wave file in your audio editor, it would be hard to conceive that we perceive that squiggly oscillating waveform as music. Our ears perform the magic. Snail-shaped organs in our inner ears contain many tiny hairs that vibrate in response to a waveform. Which hairs vibrate determine the notes we hear. Even if you are not musically trained sufficiently to name the notes being played, the fact is you perceive music as a set of notes, not as the oscillating waveform that initially enters your ear canal.
What may be rudimentary to us is often not so simple for computers, and automated music conversion is no exception. Since computers cannot truly hear like we can, intelliScore converts music by doing what computers do best - computations. In fact, intelliScore performs several million calculations to convert a single piece of music.
It is important to note that a single audio file can be interpreted as several different combinations of notes. To prove this point, try this challenge with your friends: Give each of your friends a duplicate recording of a song. To make it as interesting as possible, be sure the song uses several different instruments including percussion. Have each person independently figure out all notes being played and create a MIDI file from them. They can take as much time and listen to the recording as many times as they want. Now compare the MIDI files, and you will find that they are not the same! The differences are most pronounced in passages of music containing instruments having a bright timbre. Is the sound created by many muted instruments playing different notes or a few bright instruments? Now have intelliScore create a MIDI file from the recording. IntelliScore will give you a solution that represents the "essence" of the music, that is, the prominent chords and melody lines but not necessarily some of the more subtle parts. Its results may be different than what you would have come up with. However, even if though you may clean up the MIDI files created by intelliScore, you will be spared of many hours of tedious effort of notating the song from scratch.
Of course our ears are not the only organs that help us to hear. The other is our brain. This is where we determine what set of notes are being played based upon our understanding of what notes belong together, and then decide whether or not we like these patterns. The study of these patterns is known as music theory. IntelliScore uses music theory, among other things, to help it convert music.
Notes About MIDI
A Note About Accuracy and Speed