Changeset e6f7a4a

Timestamp:

Mar 8, 2013, 4:12:17 PM (12 years ago)

Author:

Paul Brossier <piem@piem.org>

Branches:

feature/autosink, feature/cnn, feature/cnn_org, feature/constantq, feature/crepe, feature/crepe_org, feature/pitchshift, feature/pydocstrings, feature/timestretch, fix/ffmpeg5, master, pitchshift, sampler, timestretch, yinfft+

Children:

459e46f

Parents:

92c83ccc

Message:

demos/demo_onset.py: add simple onset example, update demo_onset_plot.py

Location:

python/demos

Files:

• demo_onset.py (added)
• demo_onset_plot.py (moved) (moved from python/demos/demo_onset_file.py) (1 diff)

python/demos/demo_onset_plot.py

@@ -7 +7 @@
 win_s = 512                 # fft size
 hop_s = win_s / 2           # hop size
-samplerate = 44100
-downsample = 2              # used to plot n samples / hop_s
 
 if len(sys.argv) < 2:
-    print "Usage: %s <filename>" % sys.argv[0]
+    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 = onset("default", win_s, hop_s)
+
+# onset detection delay, in blocks
+delay = 4. * hop_s
+
 onsets = []
 
-s = source(filename, samplerate, hop_s)
-o = onset("default", win_s, hop_s)
-
+# storage for plotted data
 desc = []
 tdesc = []
+allsamples_max = zeros(0,)
+downsample = 2  # to plot n samples / hop_s
 
-block_read = 0
-allsamples_max = zeros(0,)
+total_frames = 0
 while True:
     samples, read = s()
+    is_onset = o(samples)
+    if is_onset:
+        this_onset = int(total_frames - delay + is_onset[0] * hop_s)
+        print "%f" % (this_onset / float(samplerate))
+        onsets.append(this_onset / float(samplerate))
+    # 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])
-    isbeat = o(samples)
     desc.append(o.get_descriptor())
     tdesc.append(o.get_thresholded_descriptor())
-    if isbeat:
-        thisbeat = (block_read - 4. + isbeat[0]) * hop_s / samplerate
-        print "%.4f" % thisbeat
-        onsets.append (thisbeat)
-    block_read += 1
+    total_frames += read
     if read < hop_s: break