Source separation, stem separation or de-mixing are all different ways of referring to the same problem of recovering the mono-instruments tracks that were mixed together to produce a music file. Recently, the research team at Deezer released a free and open source software as well as trained models to perform multi-source separation of music, with state-of-the-art accuracy. In this presentation we come back on our journey to open sourcing Spleeter library, from doing the ground research, training the models, to releasing them. We put emphasis on the technological challenges that had to be solved as well as the practical and legal considerations that came into play.
