ref: c4c51309beb1476e54845bdca78fe46f64449c7c
dir: /python/demos/demo_tempo_plot.py/
#! /usr/bin/env python import sys from aubio import tempo, source win_s = 512 # fft size hop_s = win_s / 2 # hop size if len(sys.argv) < 2: print "Usage: %s <filename> [samplerate]" % sys.argv[0] sys.exit(1) filename = sys.argv[1] samplerate = 0 if len( sys.argv ) > 2: samplerate = int(sys.argv[2]) s = source(filename, samplerate, hop_s) samplerate = s.samplerate o = tempo("default", win_s, hop_s, samplerate) # tempo detection delay, in samples # default to 4 blocks delay to catch up with delay = 4. * hop_s # 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) total_frames += read if read < hop_s: break if len(beats) > 1: # do plotting from numpy import array, arange, mean, median, diff import matplotlib.pyplot as plt bpms = 60./ diff(beats) print 'mean period:', "%.2f" % mean(bpms), 'bpm', 'median', "%.2f" % median(bpms), 'bpm' print 'plotting', filename plt1 = plt.axes([0.1, 0.75, 0.8, 0.19]) plt2 = plt.axes([0.1, 0.1, 0.8, 0.65], sharex = plt1) plt.rc('lines',linewidth='.8') for stamp in beats: plt1.plot([stamp, stamp], [-1., 1.], '-r') plt1.axis(xmin = 0., xmax = total_frames / float(samplerate) ) plt1.xaxis.set_visible(False) plt1.yaxis.set_visible(False) # plot actual periods plt2.plot(beats[1:], bpms, '-', label = 'raw') # plot moving median of 5 last periods median_win_s = 5 bpms_median = [ median(bpms[i:i + median_win_s:1]) for i in range(len(bpms) - median_win_s ) ] plt2.plot(beats[median_win_s+1:], bpms_median, '-', label = 'median of %d' % median_win_s) # plot moving median of 10 last periods median_win_s = 20 bpms_median = [ median(bpms[i:i + median_win_s:1]) for i in range(len(bpms) - median_win_s ) ] plt2.plot(beats[median_win_s+1:], bpms_median, '-', label = 'median of %d' % median_win_s) plt2.axis(ymin = min(bpms), ymax = max(bpms)) #plt2.axis(ymin = 40, ymax = 240) plt.xlabel('time (mm:ss)') plt.ylabel('beats per minute (bpm)') plt2.set_xticklabels([ "%02d:%02d" % (t/60, t%60) for t in plt2.get_xticks()[:-1]], rotation = 50) #plt.savefig('/tmp/t.png', dpi=200) plt2.legend() plt.show() else: print 'mean period:', "%.2f" % 0, 'bpm', 'median', "%.2f" % 0, 'bpm', print 'nothing to plot, file too short?'