ref: 8924bdf04489a93fcea408d0e45347b37a0d88a8
dir: /python/demos/demo_simple_spectral_weighting.py/
#! /usr/bin/env python
import sys
from aubio import source, sink, pvoc
from numpy import arange, exp, hstack, zeros, cos
from math import pi
def gauss(size):
return exp(- 1.0 / (size * size) * pow(2.0* arange(size) - 1. *size, 2.));
def hanningz(size):
return 0.5 * (1. - cos(2.*pi*arange(size) / size))
if __name__ == '__main__':
if len(sys.argv) < 2:
print('usage: %s <inputfile> <outputfile>' % sys.argv[0])
sys.exit(1)
samplerate = 0
if len(sys.argv) > 3: samplerate = int(sys.argv[3])
f = source(sys.argv[1], samplerate, 256)
samplerate = f.samplerate
g = sink(sys.argv[2], samplerate)
win_s = 512 # fft size
hop_s = win_s // 2 # hop size
pv = pvoc(win_s, hop_s) # phase vocoder
# spectral weighting vector
spec_weight = hstack ( [
.8 * hanningz(80)[40:],
zeros( 50 ),
1.3 * hanningz(100),
zeros (win_s // 2 + 1 - 40 - 50 - 100),
] )
if 0:
from pylab import plot, show
plot(spec_weight)
show()
total_frames, read = 0, hop_s
while read:
# get new samples
samples, read = f()
# compute spectrum
spectrum = pv(samples)
# apply weight to spectral amplitudes
spectrum.norm *= spec_weight
# resynthesise modified samples
new_samples = pv.rdo(spectrum)
# write to output
g(new_samples, read)
total_frames += read
duration = total_frames / float(samplerate)
print("read {:.3f}s from {:s}".format(duration, f.uri))