Exemplo n.º 1
0
def fft_filter(v_frm_short_a, shift_a, v_spec_diff_db_a, fft_len):

    # dB to absolute:
    v_spec_diff_a = la.db(v_spec_diff_db_a, b_inv=True)

    right_a = v_frm_short_a.size - shift_a
    v_frm_short_a_ext = np.r_[np.zeros(fft_len/2 - shift_a) ,  v_frm_short_a , np.zeros(fft_len/2 - right_a)]
    v_fft_frm_short_a_ext = np.fft.fft(v_frm_short_a_ext) * la.add_hermitian_half(v_spec_diff_a[None,:], data_type='mag')[0]

    # To time domain:
    v_frm_short_a_ext_filt = np.fft.ifft(v_fft_frm_short_a_ext).real

    return v_frm_short_a_ext_filt
Exemplo n.º 2
0
def synthesis_from_lossless(m_mag, m_real, m_imag, v_shift):

    m_ph_cmpx = m_real + m_imag * 1j

    ### with protection against divide-by-zero:
    m_ph_cmpx_mag = np.absolute(m_ph_cmpx)
    m_ph_cmpx_mag[m_ph_cmpx_mag==0.0] = 1.0
    m_fft     = m_mag * m_ph_cmpx / m_ph_cmpx_mag

    m_fft     = la.add_hermitian_half(m_fft, data_type='complex')
    m_frm     = np.fft.ifft(m_fft).real
    m_frm     = np.fft.fftshift(m_frm,  axes=1)
    v_pm      = la.shift_to_pm(v_shift)

    v_syn_sig = mp.ola(m_frm,v_pm)

    return v_syn_sig
Exemplo n.º 3
0
def get_formant_locations_from_raw_long_frame(v_sig, v_pm, nx, fft_len):
    '''
    nx: frame index
    '''

    #v_sig, fs = la.read_audio_file(wavfile)

    # Epoch detection:
    #v_pm_sec, v_voi = la.reaper_epoch_detection(wavfile)
    #v_pm = lu.round_to_int(v_pm_sec * fs)

    # Raw-long Frame extraction:

    v_frm_long = v_sig[v_pm[nx-2]:v_pm[nx+2]+1]

    # Win:
    left_len  = v_pm[nx] - v_pm[nx-2]
    right_len = v_pm[nx+2] - v_pm[nx]
    v_win = la.gen_non_symmetric_win(left_len, right_len, np.hanning, b_norm=False)
    v_frm_long_win = v_frm_long * v_win

    # Spectrum:
    v_mag = la.remove_hermitian_half(np.absolute(np.fft.fft(v_frm_long_win, n=fft_len)[None,:]))[0]
    v_mag_db = la.db(v_mag)

    # Mel warping:
    alpha = 0.50  # 0.55 - 0.60
    #ncoeffs = 2048 # must be even
    v_mag_mel      = la.sp_mel_warp(v_mag[None,:], fft_len/2, alpha=alpha, in_type=3)[0]
    v_sp_cmplx     = la.build_min_phase_from_mag_spec(v_mag_mel[None,:])[0]
    v_sp_cmplx_ext = la.add_hermitian_half(v_sp_cmplx[None,:], data_type='complex')[0]
    v_frm_long_win_mel = np.fft.ifft(v_sp_cmplx_ext).real

    if False:
        plt.close('all')
        pl(la.db(v_mag))
        pl(la.db(np.absolute(v_sp_cmplx)))
        pl(v_frm_long_win_mel)

    # Formant extraction -LPC method:--------------------------------------------------
    n_lpc_coeffs = 30 # 40
    v_lpc_mel, v_e, v_refl = lpc(v_frm_long_win_mel, n_lpc_coeffs)

    v_lpc_mag_mel = lpc_to_mag(v_lpc_mel, fft_len=fft_len)
    v_lpc_mag_mel_db = la.db(v_lpc_mag_mel)
    v_lpc_mag_mel_db = v_lpc_mag_mel_db - np.mean(v_lpc_mag_mel_db) + np.mean(la.db(v_mag_mel))

    v_frmnts_bins_mel, v_frmnts_gains_db = get_formant_locations_from_spec_env(v_lpc_mag_mel_db)

    # Getting bandwidth:
    fft_len_half = 1 + fft_len / 2
    v_vall_bins = get_formant_locations_from_spec_env(-v_lpc_mag_mel_db)[0]
    v_vall_bins = np.r_[0, v_vall_bins, fft_len_half-1]

    nfrmnts = v_frmnts_bins_mel.size
    v_frmnts_bw_mel = np.zeros(nfrmnts) - 1.0
    for nx_f in xrange(nfrmnts):
        #Left slope:
        curr_frmnt_bin  = v_frmnts_bins_mel[nx_f]
        curr_vall_l_bin = v_vall_bins[nx_f]
        curr_vall_r_bin = v_vall_bins[nx_f+1]

        curr_midp_l = int((curr_frmnt_bin + curr_vall_l_bin) / 2.0)
        curr_midp_r = int((curr_frmnt_bin + curr_vall_r_bin) / 2.0)

        # Protection:
        if curr_midp_l==curr_frmnt_bin:
            curr_midp_l = curr_vall_l_bin
        if curr_midp_r==curr_frmnt_bin:
            curr_midp_r = curr_vall_r_bin

        #print(nx_f)
        # 27 y 32
        slope_l = (v_frmnts_gains_db[nx_f] - v_lpc_mag_mel_db[curr_midp_l]) / (curr_frmnt_bin - curr_midp_l).astype(float)
        slope_r = (v_frmnts_gains_db[nx_f] - v_lpc_mag_mel_db[curr_midp_r]) / (curr_frmnt_bin - curr_midp_r).astype(float)

        slope_ave = (slope_l - slope_r) / 2.0

        v_frmnts_bw_mel[nx_f] = 1.0 / slope_ave

    # Filtering by bandwidth:
    # bw_thress         = 7.0
    # v_frmnts_bins_mel     = v_frmnts_bins_mel[v_frmnts_bw_mel<bw_thress]
    # v_frmnts_gains_db = v_frmnts_gains_db[v_frmnts_bw_mel<bw_thress]
    # v_frmnts_bw_mel       = v_frmnts_bw_mel[v_frmnts_bw_mel<bw_thress]

    # Computing frame short:--------------------------------
    # Win:
    left_len_short  = v_pm[nx] - v_pm[nx-1]
    right_len_short = v_pm[nx+1] - v_pm[nx]
    v_win_short = la.gen_non_symmetric_win(left_len_short, right_len_short, np.hanning, b_norm=False)
    v_frm_short = v_sig[v_pm[nx-1]:v_pm[nx+1]+1]
    v_frm_short_win = v_frm_short * v_win_short
    shift = v_pm[nx] - v_pm[nx-1]

    # Formant extraction - True envelope method:----------------------------------------
    # Not finished.
    #v_true_env_db = la.true_envelope(v_mag_db[None,:], in_type='db', ncoeffs=400, thres_db=0.1)[0]

    if True:
        plt.figure(); plt.plot(la.db(v_mag_mel)); plt.plot(v_lpc_mag_mel_db); plt.grid(); plt.show()
        #pl(v_mag_db)
        if True: import ipdb; ipdb.set_trace(context=8)  # breakpoint 906d26d6 //


    return v_mag_db, v_lpc_mag_mel_db, v_frmnts_bins_mel, v_frmnts_gains_db, v_frmnts_bw_mel, v_frm_short_win, shift