I know little of the topic, but the end result sounds equivalent to methods that convert a music recording to a MIDI file. There is a list of such programs at h

I know little of the topic, but the end result sounds equivalent to methods that convert a music recording to a MIDI file. There is a list of such programs at http://wiki.audacityteam.org/wiki/Midi#Converting_from_audio_formats_to_MIDI http://wiki.audacityteam.org/wiki/Midi#Converting_from_audio... . That section does comment that this is a challenging research problem.