python/demos/demo_waveform_plot.py: plot more samples, add hop_size parameter, add...

diff --git a/python/demos/demo_waveform_plot.py b/python/demos/demo_waveform_plot.py
index 7ab457a3070f55632bc049bb6e685f2be2003964..41314670ec206f74beb820249d17e29f07423354 100755 (executable)
--- a/python/demos/demo_waveform_plot.py
+++ b/python/demos/demo_waveform_plot.py
@@ -4,15 +4,15 @@ import sys
 from aubio import pvoc, source
 from numpy import zeros, hstack
 
-def get_waveform_plot(filename, samplerate = 0, ax = None):
+def get_waveform_plot(filename, samplerate = 0, block_size = 4096, ax = None):
     import matplotlib.pyplot as plt
     if not ax:
         fig = plt.figure()
         ax = fig.add_subplot(111)
-    hop_s = 4096 # block size
+    hop_s = block_size
 
     allsamples_max = zeros(0,)
-    downsample = 2**3  # to plot n samples / hop_s
+    downsample = 2**4  # to plot n samples / hop_s
 
     a = source(filename, samplerate, hop_s)            # source file
     if samplerate == 0: samplerate = a.samplerate
@@ -25,8 +25,6 @@ def get_waveform_plot(filename, samplerate = 0, ax = None):
         allsamples_max = hstack([allsamples_max, new_maxes])
         total_frames += read
         if read < hop_s: break
-    print samples.reshape(hop_s/downsample, downsample).shape
-
     allsamples_max = (allsamples_max > 0) * allsamples_max
     allsamples_max_times = [ ( float (t) / downsample ) * hop_s for t in range(len(allsamples_max)) ]
 
@@ -34,12 +32,18 @@ def get_waveform_plot(filename, samplerate = 0, ax = None):
     ax.plot(allsamples_max_times, -allsamples_max, '-b')
     ax.axis(xmin = allsamples_max_times[0], xmax = allsamples_max_times[-1])
 
-    if allsamples_max_times[-1] / float(samplerate) > 60:
+    set_xlabels_sample2time(ax, allsamples_max_times[-1], samplerate)
+    return ax
+
+def set_xlabels_sample2time(ax, latest_sample, samplerate):
+    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: