A new version of Chromaprint has been released. The main change is addition of an example application that uses the public C API and FFmpeg to allow externals programs to use Chromaprint without linking to the library. Other than this, there were some build system changes and added support for the latest development version of FFmpeg. Download: Source code tarball (529K) Ubuntu packages Static binaries for the fpcalc tool: Windows, x86 (633K) Mac OS X, x86, 10.

Some time ago I realized that having the server code in Java keeps me away from working more on it. The original reason for writing it in Java was that I expected it would do harder work, but I really don’t need a “fast” language for simply running SQL queries. Additionally, since developing simple websites in Java turned out to be a pain, I used PHP to do the Acoustid website.

A new version of Chromaprint has been released. There aren’t many changes, mostly just compatibility improvements for Windows and Mac OS X, plus simple ctypes-based Python bindings. Download: Source code tarball (526K) Ubuntu packages Changes since version 0.2: Fixed compilation with MSVC 2010. Added support for calculating FFT using the Accelerate framework on Mac OS X and iOS. Added Python bindings.

Last week, with the help from Zvooq , the Acoustid service was moved one more time , this time to a much more powerful server. This move made it possible to import all submissions from the backlog, so the database now contains fingerprints for over 5M unique tracks. Unfortunately, only around 2.4M of them are matched to the MusicBrainz database, but I’m hoping that the ratio will improve soon. There are a couple of things on my roadmap:

I’m not good at releasing code, as this should have been done a long time ago, but I’ve finally released the version 0.2 of Chromaprint. The main changes are new functions in the public API for working with raw fingerprints and safe releasing of memory allocated internally in Chromaprint. Download: Source code tarball (520K) Ubuntu packages Changes since version 0.1: New public functions chromaprint_{encode,decode}_fingerprint for encoding/decoding raw fingerprints.

I’ve been meaning to write this post for a long time, but never really finished it. I hope it will help people understand how does the Chromaprint algorithm work, where do the individual ideas come from and what do the fingerprints really represent. It’s not meant to be a detailed description, just the basics to get the general idea. Being primarily based on the Computer Vision for Music Identification paper, images play an important role in the algorithm.

I’ve finally written a script to take a consistent dump of the Acoustid database in the PostgreSQL tab-separated format used by the COPY command. I do not have any tools for importing it into PostgreSQL, so it has to be done manually by running SQL commands, but if anybody is interested in playing with the database, you can download it here (2.7G after compression using bzip2, 6.4G uncompressed). The data is licensed under a Creative Commons BY-SA 3.

As strange as it might sound, the Acoustid submission API can now also accept PUIDs instead of MBIDs . I had the idea of using PUIDs to help bootstrap the Acoustid database for a long time, but I avoided implementing it, because I was afraid of bringing all the PUID↔MBID matching errors to the database. The topic came up yesterday and I realized that with having the audio fingerprints, MBIDs and MusicBrainz metadata in the same database, I can pretty easily remove any suspicious matches.

Since I announced the Acoustid project, I got over 1.1 million fingerprint submissions (mostly from MusicBrainz editors ), covering about 580 thousand unique MusicBrainz track IDs. In the background I was running a process that imported the raw submissions and merged similar tracks. All this was done on a virtual machine with 1GB of RAM. It wasn’t very fast, but I was surprised it was even able to handle such amount of data.

After posting about the beta version of Acoustid Fingerprinter, some people successfully used it to submit fingerprints and I also started using it as the main tool for submitting fingerprints, so I think it’s time for a proper release. More details on the wiki: Acoutid Fingerprinter 0.1 Chromaprint 0.1 If you are using Windows, you can simply download and unzip the binary package. On Ubuntu (Lucid, Karmic and Maverick), you can install it from my PPA: