Beats-Per-Minute Provider

Overview

This provider is able to analyze an audio file path in order to find the average beats-per-minute rate.

Usage Example:

>>> from munin.provider import BPMProvider
>>> p = BPMProvider()
>>> p.do_process('/tmp/some_file.mp3')
(123.456, )  # beats per minute

The potential Information you can get from this is: Songs of different genre often have differente tempi, therefore are less similar. This is no rule of course.

Problems to consider:

• Noisy Live-data often gets high BPM counts
• Speed-Metal (as an example) ranges in the same

Prerequisites:

To function properly this poorly implemented provider needs two external utils:

• http://sox.sourceforge.net/
• http://www.pogo.org.uk/~mark/bpm-tools/

Reference

class munin.provider.bpm.BPMProvider(compress=False)

A Beats-per-minute provider.

Currently, this is stupidly implemented as a call to an external util:

$ sox -v 1.0 path -t raw -r 44100 -e float -c 1 - | bpm -m 60 -x 350

More Information on beats per minute:

http://en.wikipedia.org/wiki/Tempo#Beats_per_minute

Create a new Provider with the following attributes:

Parameters:compress – Deduplicate data?

class munin.provider.bpm.BPMCachedProvider(cache_invalid=False, **kwargs)

Same as BPMProvider, but adds a caching layer.

A .bpm file with the calculated value will be stored along the audio file, and the same place will be checked before actually calculating it.

Parameters:cache_invalid – Also cache invalid results of failed calculations?