Presentation at the workshop "Music, Mind, Invention", 31.March 2012, Ewing (New Jersey). This presentation was given with the PREZI software. The original version with PREZI is here: http://prezi.com/i9ydgu8tz8wj/from-music-to-visuals-and-back-2d-fourier-transform-applied-on-music-piano-roll-plots/?kw=view-i9ydgu8tz8wj&rc=ref-3095459