ref: b1c2acc0c013e232d8a5e051b7b3744707dd24c1
parent: 89fd1e51ade2960fddfd27406353f80c4e519c3e
author: Paul Brossier <[email protected]>
date: Fri Jul 27 06:36:29 EDT 2012
demo_spectrogram.py: clarify, use log10(norm)
--- a/interfaces/python/demo_spectrogram.py
+++ b/interfaces/python/demo_spectrogram.py
@@ -3,29 +3,30 @@
import sys
from aubio import pvoc, source
from numpy import array, arange, zeros, shape, log10, vstack
-from pylab import imshow, show, gray, autumn, axis, ylabel, xlabel, xticks, yticks
+from pylab import imshow, show, cm, axis, ylabel, xlabel, xticks, yticks
def get_spectrogram(filename):
- win_s = 512 # fft size
- hop_s = win_s / 2 # hop size
- fft_s = win_s / 2 + 1 # number of spectrum bins
- samplerate = 16000
- specgram = zeros([0, fft_s], dtype='float32')
- a = source(filename, samplerate, hop_s) # mono 8kHz only please
+ samplerate = 44100
+ win_s = 512 # fft window size
+ hop_s = win_s / 2 # hop size
+ fft_s = win_s / 2 + 1 # spectrum bins
+
+ a = source(filename, samplerate, hop_s) # source file
pv = pvoc(win_s, hop_s) # phase vocoder
+ specgram = zeros([0, fft_s], dtype='float32') # numpy array to store spectrogram
+
+ # analysis
while True:
samples, read = a() # read file
- #specgram = vstack((specgram,1.-log10(1.+pv(samples).norm))) # store new norm vector
specgram = vstack((specgram,pv(samples).norm)) # store new norm vector
if read < a.hop_size: break
- autumn()
- from pylab import gray
- gray()
- imshow(specgram.T, origin = 'bottom', aspect = 'auto')
+ # plotting
+ imshow(log10(specgram.T), origin = 'bottom', aspect = 'auto', cmap=cm.gray_r)
axis([0, len(specgram), 0, len(specgram[0])])
ylabel('Frequency (Hz)') xlabel('Time (s)')+ # show axes in Hz and seconds
time_step = hop_s / float(samplerate)
total_time = len(specgram) * time_step
ticks = 10
@@ -33,9 +34,12 @@
[x * total_time / float(ticks) for x in range(ticks) ] )
yticks( arange(ticks) / float(ticks) * len(specgram[0]),
[x * samplerate / 2. / float(ticks) for x in range(ticks) ] )
- show()
-if len(sys.argv) < 2:
- print "Usage: %s <filename>" % sys.argv[0]
-else:
- [get_spectrogram(soundfile) for soundfile in sys.argv[1:]]
+if __name__ == '__main__':
+ if len(sys.argv) < 2:
+ print "Usage: %s <filename>" % sys.argv[0]
+ else:
+ for soundfile in sys.argv[1:]:
+ get_spectrogram(soundfile)
+ # display graph
+ show()