We’re happy to announce Magenta, a project from the Google Brain team that asks: Can we use machine learning to create compelling art and music? If so, how? If not, why not? We’ll use TensorFlow, and we’ll release our models and tools in open source on our GitHub. We’ll also post demos, tutorial blog postings and technical papers. Soon we’ll begin accepting code contributions from the community at large. If you’d like to keep up on Magenta as it grows, you can follow us on our GitHub and join our discussion group.
What is Magenta?
Magenta has two goals. First, it’s a research project to advance the state of the art in machine intelligence for music and art generation. Machine learning has already been used extensively to understand content, as in speech recognition or translation. With Magenta, we want to explore the other side—developing algorithms that can learn how to generate art and music, potentially creating compelling and artistic content on their own.
Second, Magenta is an attempt to build a community of artists, coders and machine learning researchers. The core Magenta team will build open-source infrastructure around TensorFlow for making art and music. We’ll start with audio and video support, tools for working with formats like MIDI, and platforms that help artists connect to machine learning models. For example, we want to make it super simple to play music along with a Magenta performance model.
We don’t know what artists and musicians will do with these new tools, but we’re excited to find out. Look at the history of creative tools. Daguerre and later Eastman didn’t imagine what Annie Liebovitz or Richard Avedon would accomplish in photography. Surely Rickenbacker and Gibson didn’t have Jimi Hendrix or St. Vincent in mind. We believe that the models that have worked so well in speech recognition, translation and image annotation will seed an exciting new crop of tools for art and music creation.
To start, Magenta is being developed by a small team of researchers from the Google Brain team. If you’re a researcher or a coder, you can check out our alpha-version code. Once we have a stable set of tools and models, we’ll invite external contributors to check in code to our GitHub. If you’re a musician or an artist (or aspire to be one—it’s easier than you might think!), we hope you’ll try using these tools to make some noise or images or videos… or whatever you like.
Our goal is to build a community where the right people are there to help out. If the Magenta tools don’t work for you, let us know. We encourage you to join our discussion list and shape how Magenta evolves. We’d love to know what you think of our work—as an artist, musician, researcher, coder, or just an aficionado. You can follow our progress and check out some of the music and art Magenta helps create right here on this blog. As we begin accepting code from community contributors, the blog will also be open to posts from these contributors, not just Google Brain team members.
We’ll talk about our research goals in more depth later, via a series of tutorial blog postings. But here’s a short outline to give an idea of where we’re heading.
Our main goal is to design algorithms that learn how to generate art and music. There’s been a lot of great work in image generation from neural networks, such as DeepDream from A. Mordvintsev et al. at Google and Neural Style Transfer from L. Gatys et al. at U. Tübingen. We believe this area is in its infancy, and expect to see fast progress here. For those following machine learning closely, it should be clear that this progress is already well underway. But there remain a number of interesting questions: How can we make models like these truly generative? How can we better take advantage of user feedback?
Attention and Surprise
It’s not enough just to sample images or sequences from some learned distribution. Art is dynamic! Artists and musicians draw our attention to one thing at the expense of another. They change their story over time—is any Beatles album exactly like another?—and there’s always some element of surprise at play. How do we capture effects like attention and surprise in a machine learning model? While we don’t have a complete answer for this question, we can point to some interesting models such as the Show, Attend and Tell model by Xu et al. from the MILA lab in Montreal that learns to control an attentional lens, using it to generate descriptive sentences of images.
This leads to perhaps our biggest challenge: combining generation, attention and surprise to tell a compelling story. So much machine-generated music and art is good in small chunks, but lacks any sort of long-term narrative arc. (To be fair, my own 2002 music generation work falls into this category). Alternately, some machine generated content does have long-term structure, but that structure is provided TO rather than learned BY the algorithm. This is the case, for example, in David Cope’s very interesting Experiments in Musical Intelligence (EMI), in which an AI model deconstructs compositions by human composers, finds common signatures in them, and recombines them into new works. The design of models that learn to construct long narrative arcs is important not only for music and art generation, but also areas like language modeling, where it remains a challenge to carry meaning even across a long paragraph, much less whole stories. Attention models like the Show, Attend and Tell point to one promising direction, but this remains a very challenging task.
Evaluating the output of generative models is deceivingly difficult. The time will come when Magenta has 20 different music generation models available in open source. How do we decide which ones are good? One option is to compare model output to training data by measuring likelihood. For music and art, this doesn’t work very well. As argued very nicely in A note on generative models (Theis et al.), it’s easy to generate outputs that are close in terms of likelihood, but far in terms of appeal (and vice versa). This motivates work in artificial adversaries such as Generative Adversarial Nets by Goodfellow et al. from MILA in Montreal. In the end, to answer the evaluation question we need to get Magenta tools in the hands of artists and musicians, and Magenta media in front of viewers and listeners. As Magenta evolves, we’ll be working on good ways to achieve this.
Other Google efforts
Finally, we want to mention other Google efforts and resources related to Magenta. The Artists and Machine Intelligence (AMI) project is connecting with artists to ask: What do art and technology have to do with each other? What is machine intelligence, and what does ‘machine intelligence art’ look, sound and feel like? Check out their blog for more about AMI.
The Google Cultural Institute is fostering the discovery of exhibits and collections from museums and archives all around the world. Via their Lab at the Cultural Institute, they’re also connecting directly with artists. As we make TensorFlow/Magenta the best machine learning platform in the world for art and music generation, we’ll work closely with both AMI and the Google Cultural Institute to connect artists with technology. To learn more about our various efforts, be sure to check out the Google Research Blog.