I am currently looking around for a good allround beat detection library / source code in C++ since I found it really hard to achieve satisfying results with the beat detection code I wrote myself using this tutorial: http://www.gamedev.net/reference/programming/features/beatdetection/
It's especially really hard if you want to make it work with any kind of music so I was wondering if there is something usable out there allready?
Thanks!
You could try Aubio: http://aubio.org/
It does not seem to work (at least for me, today) in windows, but it does work in OS/X