  Music is an art, perceived in unique ways by every listener, coming from
acoustic signals. In the meantime, standards as musical scores exist to
describe it. Even if humans can make this transcription, it is costly in terms
of time and efforts, even more with the explosion of information consecutively
to the rise of the Internet. In that sense, researches are driven in the
direction of Automatic Music Transcription. While this task is considered
solved in the case of single notes, it is still open when notes superpose
themselves, forming chords. This report aims at developing some of the existing
techniques towards Music Transcription, particularly matrix factorization, and
introducing the concept of multi-channel automatic music transcription. This
concept will be explored with mathematical objects called tensors.
