4 from aubio import tempo, source
7 hop_s = win_s / 2 # hop size
10 print "Usage: %s <filename> [samplerate]" % sys.argv[0]
13 filename = sys.argv[1]
16 if len( sys.argv ) > 2: samplerate = int(sys.argv[2])
18 s = source(filename, samplerate, hop_s)
19 samplerate = s.samplerate
20 o = tempo("default", win_s, hop_s, samplerate)
22 # tempo detection delay, in samples
23 # default to 4 blocks delay to catch up with
26 # list of beats, in samples
29 # total number of frames read
35 this_beat = o.get_last_s()
36 beats.append(this_beat)
38 if read < hop_s: break
42 from numpy import array, arange, mean, median, diff
43 import matplotlib.pyplot as plt
44 bpms = 60./ diff(beats)
45 print 'mean period:', "%.2f" % mean(bpms), 'bpm', 'median', "%.2f" % median(bpms), 'bpm'
46 print 'plotting', filename
47 plt1 = plt.axes([0.1, 0.75, 0.8, 0.19])
48 plt2 = plt.axes([0.1, 0.1, 0.8, 0.65], sharex = plt1)
49 plt.rc('lines',linewidth='.8')
50 for stamp in beats: plt1.plot([stamp, stamp], [-1., 1.], '-r')
51 plt1.axis(xmin = 0., xmax = total_frames / float(samplerate) )
52 plt1.xaxis.set_visible(False)
53 plt1.yaxis.set_visible(False)
56 plt2.plot(beats[1:], bpms, '-', label = 'raw')
58 # plot moving median of 5 last periods
60 bpms_median = [ median(bpms[i:i + median_win_s:1]) for i in range(len(bpms) - median_win_s ) ]
61 plt2.plot(beats[median_win_s+1:], bpms_median, '-', label = 'median of %d' % median_win_s)
62 # plot moving median of 10 last periods
64 bpms_median = [ median(bpms[i:i + median_win_s:1]) for i in range(len(bpms) - median_win_s ) ]
65 plt2.plot(beats[median_win_s+1:], bpms_median, '-', label = 'median of %d' % median_win_s)
67 plt2.axis(ymin = min(bpms), ymax = max(bpms))
68 #plt2.axis(ymin = 40, ymax = 240)
69 plt.xlabel('time (mm:ss)')
70 plt.ylabel('beats per minute (bpm)')
71 plt2.set_xticklabels([ "%02d:%02d" % (t/60, t%60) for t in plt2.get_xticks()[:-1]], rotation = 50)
73 #plt.savefig('/tmp/t.png', dpi=200)
78 print 'mean period:', "%.2f" % 0, 'bpm', 'median', "%.2f" % 0, 'bpm',
79 print 'nothing to plot, file too short?'