ref: c911b121883f3deff01e97fd5bf11a28d056f06b
parent: d47a5e19c1969a4dcf26bb7a9696609bb16b9107
author: Paul Brossier <piem@piem.org>
date: Mon Dec 2 07:40:05 EST 2013
python/demos/demo_bpm_extract.py: add simple demo to get bpm of several files
--- /dev/null
+++ b/python/demos/demo_bpm_extract.py
@@ -1,0 +1,54 @@
+#! /usr/bin/env python
+
+from aubio import source, tempo
+from numpy import median, diff
+
+def get_file_bpm(path, params = {}):+ """ Calculate the beats per minute (bpm) of a given file.
+ path: path to the file
+ param: dictionary of parameters
+ """
+ try:
+ win_s = params['win_s']
+ samplerate = params['samplerate']
+ hop_s = params['hop_s']
+ except:
+ """
+ # super fast
+ samplerate, win_s, hop_s = 4000, 128, 64
+ # fast
+ samplerate, win_s, hop_s = 8000, 512, 128
+ """
+ # default:
+ samplerate, win_s, hop_s = 44100, 1024, 512
+
+ s = source(path, samplerate, hop_s)
+ samplerate = s.samplerate
+ o = tempo("specdiff", win_s, hop_s, samplerate)+ # List of beats, in samples
+ beats = []
+ # Total number of frames read
+ total_frames = 0
+
+ while True:
+ samples, read = s()
+ is_beat = o(samples)
+ if is_beat:
+ this_beat = o.get_last_s()
+ beats.append(this_beat)
+ #if o.get_confidence() > .2 and len(beats) > 2.:
+ # break
+ total_frames += read
+ if read < hop_s:
+ break
+
+ # Convert to periods and to bpm
+ bpms = 60./diff(beats)
+ b = median(bpms)
+ return b
+
+if __name__ == '__main__':
+ import sys
+ for f in sys.argv[1:]:
+ bpm = get_file_bpm(f)
+ print "%6s" % ("%.2f" % bpm), f