Music Beta was announced at the Google I/O 2011, and allows users to stream their music collections from the cloud to any supported device, including a web browser. One key component of the product, "Instant Mix" is a playlist generator developed by Google Research.
"Instant Mix uses machine hearing to extract attributes from audio which can be used to answer questions such as "Is there a Hammond B-3 organ?" (instrumentation / timbre), "Is it angry?" (mood), "Can I jog to it?" (tempo / meter) and so on. Machine learning algorithms relate these audio features to what we know about music on the web, such as the fact that Jimmy Smith is a jazz organist or that Arcade Fire and Wolf Parade are similar artists. From this we can predict similar tracks for a seed track and, with some additional sequencing logic, generate Instant Mix playlists from songs in a user's locker," explained Google.
"Because we combine audio analysis with information about which artists and albums go well together, we can use both dimensions of similarity to compare songs. If you pick a mellow track from an album, we'll make a mellower playlist than if you pick a high energy track from the same album," Google stated.
Google cites an example "here we compare short Instant Mixes made from two very different tracks by U2. The first Instant Mix comes from "Mysterious Ways," an upbeat, danceable track from Achtung Baby with electric guitar and heavy percussion."
- U2 "Mysterious Ways"
- David Bowie "Fame"
- Oingo Boingo "Gratitude"
- Infectious Grooves "Spreck"
- Red Hot Chili Peppers "Special Secret Song Inside"
Compare this to a short Instant Mix made from a much more laid back U2 cut, "MLK" from the album Unforgettable Fire. This track has delicate vocals on top of a sparse synthesizer background and no percussion.
- U2 "MLK"
- Jewel "Don't"
- Antony and the Johnsons "What Can I Do?"
- The Beatles "And I Love Her"
- Van Morrison "Crazy Love"
[Source:Google Research blog]