gistfile1.txt

import numpy
import scipy.io.wavfile
import sys

rate, inp = scipy.io.wavfile.read(sys.argv[1])
inp = [x[0] for x in inp]

print("Loaded...")

lowpass = numpy.convolve(inp, [1 / 20] * 20, mode="same")
thrs = numpy.array([0 if x < 13000 else 30000 for x in lowpass])

lasth = -1
fsth = -1
silence = 0
fcnt = 0
for i, x in enumerate(thrs):
    if x:
        silence = 0
        if fsth == -1:
            fsth = i
        lasth = i
    elif silence < 600:
        silence += 1
    elif fsth != -1 and lasth != -1:
        fsth -= 20
        lasth += 20
        print("%d @ %d - %d" % (fcnt, fsth, lasth))
        scipy.io.wavfile.write("packet-%d.wav" % fcnt, rate, thrs[fsth:lasth])
        fcnt += 1
        fsth = -1
        lasth = -1