ref: c8c7aa6a9234828d94424620ce3288d4ea1585be
dir: /python/demos/demo_waveform_plot.py/
#! /usr/bin/env python import sys from aubio import source from numpy import zeros, hstack def get_waveform_plot(filename, samplerate = 0, block_size = 4096, ax = None, downsample = 2**4): import matplotlib.pyplot as plt if not ax: fig = plt.figure() ax = fig.add_subplot(111) hop_s = block_size allsamples_max = zeros(0,) downsample = downsample # to plot n samples / hop_s a = source(filename, samplerate, hop_s) # source file if samplerate == 0: samplerate = a.samplerate total_frames = 0 while True: samples, read = a() # keep some data to plot it later new_maxes = (abs(samples.reshape(hop_s//downsample, downsample))).max(axis=0) allsamples_max = hstack([allsamples_max, new_maxes]) total_frames += read if read < hop_s: break allsamples_max = (allsamples_max > 0) * allsamples_max allsamples_max_times = [ ( float (t) / downsample ) * hop_s for t in range(len(allsamples_max)) ] ax.plot(allsamples_max_times, allsamples_max, '-b') ax.plot(allsamples_max_times, -allsamples_max, '-b') ax.axis(xmin = allsamples_max_times[0], xmax = allsamples_max_times[-1]) set_xlabels_sample2time(ax, allsamples_max_times[-1], samplerate) return ax def set_xlabels_sample2time(ax, latest_sample, samplerate): ax.axis(xmin = 0, xmax = latest_sample) if latest_sample / float(samplerate) > 60: ax.set_xlabel('time (mm:ss)') ax.set_xticklabels([ "%02d:%02d" % (t/float(samplerate)/60, (t/float(samplerate))%60) for t in ax.get_xticks()[:-1]], rotation = 50) else: ax.set_xlabel('time (ss.mm)') ax.set_xticklabels([ "%02d.%02d" % (t/float(samplerate), 100*((t/float(samplerate))%1) ) for t in ax.get_xticks()[:-1]], rotation = 50) if __name__ == '__main__': import matplotlib.pyplot as plt if len(sys.argv) < 2: print("Usage: %s <filename>" % sys.argv[0]) else: for soundfile in sys.argv[1:]: get_waveform_plot(soundfile) # display graph plt.show()