Acoustic fingerprinting is a technique for identifying songs from the way they “sound” rather from their existing metadata. That means that beets’ autotagger can theoretically use fingerprinting to tag files that don’t have any ID3 information at all (or have completely incorrect data). This plugin uses an open-source fingerprinting technology called Chromaprint and its associated Web service, called Acoustid.
Turning on fingerprinting can increase the accuracy of the autotagger—especially on files with very poor metadata—but it comes at a cost. First, it can be trickier to set up than beets itself (you need to set up the native fingerprinting library, whereas all of the beets core is written in pure Python). Also, fingerprinting takes significantly more CPU and memory than ordinary tagging—which means that imports will go substantially slower.
If you’re willing to pay the performance cost for fingerprinting, read on!
To get fingerprinting working, you’ll need to install three things: the Chromaprint library, an audio decoder, and the pyacoustid Python library.
First, you will need to install the Chromaprint dynamic library. The Chromaprint site has links to packages for major Linux distributions. On Mac OS X and Windows, you will need to build the library yourself; the site also has good directions for that.
Next, you will need a mechanism for decoding audio files supported by the audioread library. Mac OS X has a number of decoders already built into Core Audio; on Linux, you can install GStreamer for Python, FFmpeg, or MAD and pymad. (Let me know if you have a good source for installing a decoder on Windows.) How you install these will depend on your distribution. For example:
To decode audio formats (MP3, FLAC, etc.) with GStreamer, you’ll need the standard set of Gstreamer plugins. For example, on Ubuntu, install the packages gstreamer0.10-plugins-good, gstreamer0.10-plugins-bad, and gstreamer0.10-plugins-ugly.
Then, install pyacoustid itself. You can do this using pip, like so:
$ pip install pyacoustid
Once you have all the dependencies sorted out, you can enable fingerprinting by editing your .beetsconfig. Put chroma on your plugins: line. Your config file should contain something like this:
[beets]
plugins: chroma
With that, beets will use fingerprinting the next time you run beet import.