We have already learned that FFT is pointing us in the right direction, but in itself it will not be enough to finally arrive at a classifier that successfully manages to organize our scrambled directory containing songs of diverse music genres into individual genre directories. We somehow need a more advanced version of it.
At this point, it is always wise to acknowledge that we have to do more research. Other people might have had similar challenges in the past and already found out new ways that might also help us. And indeed, there is even a yearly conference only dedicated to music genre classification organized by the International Society for Music Information Retrieval (ISMIR). Apparently, Automatic Music Genre Classification (AMGC) is an established subfield of Music Information Retrieval (MIR). Glancing over some of the AMGC papers, we see that there is a bunch of work targeting automatic genre classification...
