Music Machinery

photo by by Jon Åslund

Today at the Stockholm Music Hack Day, Echo Nest co-founder Brian Whitman demoed the alpha version of a new set of Echo Nest APIs .  There are 3 new public methods and hints about a fourth API method.

• search_tracks: This is IMHO the most awesomest method in the Echo Nest API.   This method lets you search through the millions of tracks that the Echo Nest knows about.  You can search for tracks based on artist and track title of course, but you can also search based upon how people describe the artist or track (‘funky jazz’, ‘punk cabaret’, ‘screamo’.  You can constrain the return results based upon musical attributes (range of tempo, range of loudness, the key/mode), you can even constrain the results based upon the geo-location of the artist.   Finally, you can specify how you want the search results ordered. You can sort the results by tempo, loudness, key, mode, and even lat/long.This new method lets you fashion all sorts of interesting queries like:
  • Find  the slowest songs by Radiohead
  • Find  the loudest  romantic songs
  • Find  the northernmost rendition of a reggae track

  The index of tracks for this API is already quite large,  and will continue to grow as we add more music to the Echo Nest.  (but note, that this is an alpha version and thus it is subject to the whims of the alpha-god – even as I write this the index used to serve up these queries is being rebuilt so only a small fraction of our set of tracks are currently visible).  And BTW  if you are at the Stockholm Music Hack Day, look for Brian and ask him about the secret parameter that will give you some special search_tracks goodness!

  One of the things you get back from the search_tracks method is a track ID.  You can use this track ID to get the analysis for any track using the new get_analysis method.  No longer do you need to upload a track to get the analysis for it. Just search for it and we are likely to have the analysis already. This search_tracks method has been the most frequently requested method by our developers, so I’m excited to see this method be released.

• get_analysis – this method will give you the full track analysis for any track, given its track ID.  The method couldn’t be simpler, give it a track ID and you get back a big wad-o-json.  All of the track analysis, with one call.  (Note that for this alpha release, we have a separate track ID space from the main APIs, so IDs for tracks that you’ve analyzed with the released/supported APIs won’t necessarily be available with this method).
• capsule – this is an API that supports this-is-my-jam functionality.  Give the API a URL to an XSPF playlist and you’ll get back some json that points you to both a flashplayer url and an mp3 url to a capsulized version of the playlist.  In the capsulized version, the song transitions are aligned and beatmatched like an old style DJ would.

Brian also describes a new identify_track method that returns metadata for a track given the Echo Nest a set of  musical fingerprint hashcodes.  This is a method that you use in conjunction with the new Echo Nest audio fingerprinter (woah!).   If you are at the Stockholm music hackday and you are interested in solving the track resolution problem talk to  Brian about getting access to the new and nifty audio fingerprinter.

These new APIs are still in alpha – so lots of caveats surround them. To quote Brian: we may pull or throttle access to alpha APIs at a different rate from the supported ones. Please be warned that these are not production ready, we will be making enhancements and restarting servers, there will be guaranteed downtime.

The new APIs hint at the direction we are going here at the Echo Nest.  We want to continue to open up our huge quantities of data for developers, making as much of it available as we can to anyone who wants to build music apps.   These new APIs return JSON –  XML is so old fashioned. All the cool developers are using JSON as the data transport mechanism nowadays: its easy to generate, easy to parse and makes for a very nimble way to work with web-services.  We’ll be adding JSON support to all of our released APIs soon.

I’m also really excited about the new fingerprinting technology.  Here at the Echo Nest we know how hard it is to deal with artist and track resolution – and we want to solve this problem once and for all, for everybody – so we will  soon be releasing an  audio fingerprinting system.  We want to make this system as open as we can, so we’ll make all the FP data available to anyone. No secret hash-to-ID algorithms, and no private datasets.  The  Fingerprinter is fast, uses state-of-the-art audio analysis and will be backed by a dataset of fingerprint hashcodes for millions of tracks.   I’ll be writing more about the new fingerprinter soon.

These new APIs should give those lucky enough to be in Stockholm this weekend something fun to play with.  If you are at the Stockholm Hack Day and you build something cool with these new APIs you may find yourself going home with the much coveted Echo Nest sweatsedo: