gistfile1.py

import struct
import wave

import numpy
from numpy import *
from numpy.fft import fft


def main():

    w = wave.open('FGI.wav', 'r')
    data_size = w.getnframes() * w.getnchannels()
    frame_size = 0.025 # 25ms
    hop_size = 0.010 # 10ms
    data = w.readframes(data_size)
    w.close()

    data = struct.unpack('{n}h'.format(n=data_size), data)

    X = stft(data, 44100, frame_size, hop_size)

    print len(X)

    derp = X[22000]

    f = open('testdata.dat', 'w')
    count = 0
    for idx in range(len(derp['fft']) / 2):
        f.write("%s %s\n" % (count,numpy.abs(derp['fft'][idx])))
        count = count + 1
    f.close()
    

def stft(x, fs, framesz, hop):
    framesamp = int(framesz*fs)
    hopsamp = int(hop*fs)
    w = numpy.hamming(framesamp)

    X = []
    for i in range(0, len(x) - framesamp, hopsamp):
        b = numpy.array(w * x[i:i + framesamp])
        a = fft(b)
        c = numpy.fft.fftfreq(len(a))
        v = {
            'fft': numpy.fft.fftshift(a),
            'freq': numpy.fft.fftshift(c)}
        X.append(v)
    return X


if __name__ == '__main__':
    main()