bpm-tools is a package for Linux which provides a useful program for identifying the beats-per-minute (BPM) of a song.
To install bpm-tools, run the following:
# apt-get install bpm-tools libsox-fmt-mp3
To analyse and tag all files in the current directory, run the following from the root of the directory:
find ./ -type f -print0 | xargs -0 -n1 -P4 bpm-tag
Replace P4 with the number of threads to run.
It has been discovered that bmp-tag truncates the text tags of some songs. The length of truncation seems to fluctuate and the frequency of occurrence is arbitrary. Due to the high percentage of data destruction, it is advised to not use bpm-tag at this time.