Smashing magazine has a great overview of the current state of data visualization methods. There are music examples, many of which I covered in my Last.fm Visualization tools article. An interesting find was a Java tool called The Shape of Song. You can either upload a MIDI file or select one from their repertoire. The application then provides an interactive visualization of the song.



Arcs represent parts of the song that have identical passages and the diagram as a whole represents the composition’s deep structure. As compositions become more complex, the tool allows you to see very interesting patterns and relationships. MIDI files can be divided into several tracks, which typically represent different instruments or voices. The software in The Shape of Song analyzes each track separately, since each instrument often has a unique pattern of repetitions. Unfortunately tracks are represented by numbers instead of the instrument name so its difficult to tell exactly what you are looking at.