In a world first, a deep-learning algorithm has been developed that generates original melodies in a given music style, without any knowledge of musical theory.
Developed by scientists at Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, the algorithm, dubbed ‘Deep Artificial Composer’ or DAC, “trains” on sheet music of a given musical style before producing an original score in the same style of its own composition.
As a result, it does not produce audio files, but instead provides finished sheet music that humans can perform. At present DAC has been trained on Irish or Klezmer folk music, but it is designed to work with and mimic any musical style given to it.
“The deep artificial composer can produce complete melodies, with a beginning and an end, that are completely novel and that share features that we relate to style,” said EPFL scientist Florian Colombo, who developed DAC with the supervision of Wulfram Gerstner, director of the Computational Neuroscience Laboratory.
“To my knowledge, this is the first time that an artificial neural network model has produced entire and convincing melodies.”
Other AI composers have already been developed, however DAC is unique in that it does not use and implement musical theory. Instead it uses neural networks to determine probability distributions from existing melodies – that is, the likelihood of certain notes and note lengths occurring after each successive note.
DAV learns how music transitions from one note to the next, and the probability of both the pitch and the duration of the next note. Then it works through multiple scores, correcting its predictions and building up a model for that musical genre. Once it has successfully predicted 50% of successive notes and 80% of successive note durations, it is considered ‘trained’ and ready to compose its own music.
Working through note by note, DAC builds up an entire melody that is completely original, but is in the style of the music it has trained on. The result is melodies that sound completely man-made, but which are entirely produced by artificial intelligence.
Colombo playing a composition created by DAC on the cello. Images and music courtesy of EPFL
At present DAC is only able to produce melodies for one instrument or voice at a time, but Colombo hopes to in the future make it able to compose scores for entire orchestras in real-time.
This would realise an idea first proposed by mathematician Ada Lovelace in the 19th Century, but it will also likely cause fear among human composers, who join the pile of industries looking increasingly ready to be replaced by machines.
For others, though it could be hugely beneficial, bringing original music within reach of, for example, indie game developers and filmmakers.
The research was presented today at the Evostar conference in Amsterdam, the Netherlands.