[PYTHON] LPC mit Scipy

Nachdem ich den AR-Koeffizienten durch LPC erhalten hatte, versuchte ich, ihn mit weißem Rauschen zu fahren. Ich fühle, dass meine Stimme wie ein Roboter geworden ist (?). Wenn Sie das Fahrgeräusch ändern, sollten Sie auch eine andere Sprachqualität erhalten.

lpc.py

#!/usr/bin/env python

import sys
import wave
import urllib2
import getopt
import scipy as sp
import matplotlib.pyplot as plt
from scipy import linalg, signal
from scikits.talkbox.linpred.levinson_lpc import lpc

if __name__ == "__main__":
    optlist, argv = getopt.getopt( sys.argv[1:], 's:l:o:w:')

    frameLength = 512
    stepWidth = 256
    lpcOrder = 32
    chunk = 44100 * 5
    for opt, val in optlist:
        if( opt == '-s' ):
            chunk = int( val )
        elif( opt == '-w' ):
            stepWidth = int( val )
        elif( opt == '-l'):
            frameLength = int( val )
        elif( opt == '-o' ):
            lpcOrder = int( val )

    argc = len( argv )
    if( 0 < argc ):
        if( argc == 2 ):
            inFileName, outFileName = argv
        elif( argc == 1 ):
            inFileName = argv[0]
            outFileName = 'out.wav'
        wo = wave.open( inFileName, 'rb' )
    else:
        outFileName = 'out.wav'
        url = 'http://www.it.ice.uec.ac.jp/SRV-DB/archive/HENSHU00_PF00/HENSHU00_PF00_0951.wav'
        wo = wave.openfp( urllib2.urlopen( url ).fp,  'rb' )

    data = sp.fromstring( wo.readframes( chunk ), sp.int16 )
    blockData = sp.linalg.toeplitz( data[ frameLength:], data[:frameLength] )[::stepWidth, :]

    lpcCoef, lpcError, k = lpc( blockData,  lpcOrder )
    excitationSignal = sp.random.randn( frameLength )

    rows, cols = lpcCoef.shape
    responseSignal = sp.zeros( ( rows,  frameLength ) )
    synthesisSignal = sp.array( [0] * ( rows  * stepWidth + frameLength ) )
    weight = sp.sin( 2 * sp.pi * sp.r_[0:frameLength] / frameLength )
    for i in range( rows ):
        G = sp.sqrt( lpcError[ i ] )
        responseSignal[i, :] = sp.signal.lfilter( [G], lpcCoef[ i, :], excitationSignal )
        synthesisSignal[ i * stepWidth:i * stepWidth + frameLength ] +=  weight * responseSignal[ i, :]

    outputSignal = sp.int16( synthesisSignal ).tostring()
    wo = wave.open( outFileName, 'wb')
    params = ( 1, 2, 44100, len( synthesisSignal),'NONE','none')
    wo.setparams( params )
    wo.writeframes( outputSignal )
    wo.close()