/*----------------------------------------------------------------------------
* calc_st_filt - computes impulse response of A(gamma2) / A(gamma1)
* controls gain : computation of energy impulse response as
* SUMn (abs (h[n])) and computes parcor0
*----------------------------------------------------------------------------
*/
static void calc_st_filte(
Word16 *apond2, /* input : coefficients of numerator */
Word16 *apond1, /* input : coefficients of denominator */
Word16 *parcor0, /* output: 1st parcor calcul. on composed filter */
Word16 *sig_ltp_ptr, /* in/out: input of 1/A(gamma1) : scaled by 1/g0 */
Word16 long_h_st, /* input : impulse response length */
Word16 m_pst /* input : LPC order */
)
{
Word16 h[LONG_H_ST_E];
Word32 L_temp, L_g0;
Word16 g0, temp;
Word16 i;
/* compute i.r. of composed filter apond2 / apond1 */
Syn_filte(m_pst, apond1, apond2, h, long_h_st, mem_zero, 0);
/* compute 1st parcor */
calc_rc0_he(h, parcor0, long_h_st);
/* compute g0 */
L_g0 = 0L;
for(i=0; i<long_h_st; i++) {
L_temp = L_deposit_l(abs_s(h[i]));
L_g0 = L_add(L_g0, L_temp);
}
g0 = extract_h(L_shl(L_g0, 14));
/* Scale signal input of 1/A(gamma1) */
if(sub(g0, 1024)>0) {
temp = div_s(1024, g0); /* temp = 2**15 / gain0 */
for(i=0; i<L_SUBFR; i++) {
sig_ltp_ptr[i] = mult_r(sig_ltp_ptr[i], temp);
}
}
return;
}
void Coder_ld8h(
Word16 ana[], /* (o) : analysis parameters */
Word16 rate /* input : rate selector/frame =0 6.4kbps , =1 8kbps,= 2 11.8 kbps*/
)
{
/* LPC analysis */
Word16 r_l_fwd[MP1], r_h_fwd[MP1]; /* Autocorrelations low and hi (forward) */
Word32 r_bwd[M_BWDP1]; /* Autocorrelations (backward) */
Word16 r_l_bwd[M_BWDP1]; /* Autocorrelations low (backward) */
Word16 r_h_bwd[M_BWDP1]; /* Autocorrelations high (backward) */
Word16 rc_fwd[M]; /* Reflection coefficients : forward analysis */
Word16 rc_bwd[M_BWD]; /* Reflection coefficients : backward analysis */
Word16 A_t_fwd[MP1*2]; /* A(z) forward unquantized for the 2 subframes */
Word16 A_t_fwd_q[MP1*2]; /* A(z) forward quantized for the 2 subframes */
Word16 A_t_bwd[2*M_BWDP1]; /* A(z) backward for the 2 subframes */
Word16 *Aq; /* A(z) "quantized" for the 2 subframes */
Word16 *Ap; /* A(z) "unquantized" for the 2 subframes */
Word16 *pAp, *pAq;
Word16 Ap1[M_BWDP1]; /* A(z) with spectral expansion */
Word16 Ap2[M_BWDP1]; /* A(z) with spectral expansion */
Word16 lsp_new[M], lsp_new_q[M]; /* LSPs at 2th subframe */
Word16 lsf_int[M]; /* Interpolated LSF 1st subframe. */
Word16 lsf_new[M];
Word16 lp_mode; /* Backward / Forward Indication mode */
Word16 m_ap, m_aq, i_gamma;
Word16 code_lsp[2];
/* Other vectors */
Word16 h1[L_SUBFR]; /* Impulse response h1[] */
Word16 xn[L_SUBFR]; /* Target vector for pitch search */
Word16 xn2[L_SUBFR]; /* Target vector for codebook search */
Word16 code[L_SUBFR]; /* Fixed codebook excitation */
Word16 y1[L_SUBFR]; /* Filtered adaptive excitation */
Word16 y2[L_SUBFR]; /* Filtered fixed codebook excitation */
Word16 g_coeff[4]; /* Correlations between xn & y1 */
Word16 res2[L_SUBFR]; /* residual after long term prediction*/
Word16 g_coeff_cs[5];
Word16 exp_g_coeff_cs[5]; /* Correlations between xn, y1, & y2
<y1,y1>, -2<xn,y1>,
<y2,y2>, -2<xn,y2>, 2<y1,y2> */
/* Scalars */
Word16 i, j, k, i_subfr;
Word16 T_op, T0, T0_min, T0_max, T0_frac;
Word16 gain_pit, gain_code, index;
Word16 taming, pit_sharp;
Word16 sat_filter;
Word32 L_temp;
Word16 freq_cur[M];
Word16 temp;
/*------------------------------------------------------------------------*
* - Perform LPC analysis: *
* * autocorrelation + lag windowing *
* * Levinson-durbin algorithm to find a[] *
* * convert a[] to lsp[] *
* * quantize and code the LSPs *
* * find the interpolated LSPs and convert to a[] for the 2 *
* subframes (both quantized and unquantized) *
*------------------------------------------------------------------------*/
/* ------------------- */
/* LP Forward analysis */
/* ------------------- */
Autocorr(p_window, M, r_h_fwd, r_l_fwd); /* Autocorrelations */
Lag_window(M, r_h_fwd, r_l_fwd); /* Lag windowing */
Levinsone(M, r_h_fwd, r_l_fwd, &A_t_fwd[MP1], rc_fwd, old_A_fwd, old_rc_fwd); /* Levinson Durbin */
Az_lsp(&A_t_fwd[MP1], lsp_new, lsp_old); /* From A(z) to lsp */
/* -------------------- */
/* LP Backward analysis */
/* -------------------- */
/* -------------------- */
/* LP Backward analysis */
/* -------------------- */
if ( rate== G729E) {
/* LPC recursive Window as in G728 */
autocorr_hyb_window(synth, r_bwd, rexp); /* Autocorrelations */
Lag_window_bwd(r_bwd, r_h_bwd, r_l_bwd); /* Lag windowing */
/* Fixed Point Levinson (as in G729) */
Levinsone(M_BWD, r_h_bwd, r_l_bwd, &A_t_bwd[M_BWDP1], rc_bwd,
old_A_bwd, old_rc_bwd);
/* Tests saturation of A_t_bwd */
sat_filter = 0;
for (i=M_BWDP1; i<2*M_BWDP1; i++) if (A_t_bwd[i] >= 32767) sat_filter = 1;
if (sat_filter == 1) Copy(A_t_bwd_mem, &A_t_bwd[M_BWDP1], M_BWDP1);
else Copy(&A_t_bwd[M_BWDP1], A_t_bwd_mem, M_BWDP1);
/* Additional bandwidth expansion on backward filter */
Weight_Az(&A_t_bwd[M_BWDP1], GAMMA_BWD, M_BWD, &A_t_bwd[M_BWDP1]);
}
/*--------------------------------------------------*
* Update synthesis signal for next frame. *
*--------------------------------------------------*/
Copy(&synth[L_FRAME], &synth[0], MEM_SYN_BWD);
/*--------------------------------------------------------------------*
* Find interpolated LPC parameters in all subframes (unquantized). *
* The interpolated parameters are in array A_t[] of size (M+1)*4 *
*--------------------------------------------------------------------*/
if( prev_lp_mode == 0) {
Int_lpc(lsp_old, lsp_new, lsf_int, lsf_new, A_t_fwd);
}
else {
/* no interpolation */
/* unquantized */
Lsp_Az(lsp_new, A_t_fwd); /* Subframe 1 */
Lsp_lsf(lsp_new, lsf_new, M); /* transformation from LSP to LSF (freq.domain) */
Copy(lsf_new, lsf_int, M); /* Subframe 1 */
}
/* ---------------- */
/* LSP quantization */
/* ---------------- */
Qua_lspe(lsp_new, lsp_new_q, code_lsp, freq_prev, freq_cur);
/*--------------------------------------------------------------------*
* Find interpolated LPC parameters in all subframes (quantized) *
* the quantized interpolated parameters are in array Aq_t[] *
*--------------------------------------------------------------------*/
if( prev_lp_mode == 0) {
Int_qlpc(lsp_old_q, lsp_new_q, A_t_fwd_q);
}
else {
/* no interpolation */
Lsp_Az(lsp_new_q, &A_t_fwd_q[MP1]); /* Subframe 2 */
Copy(&A_t_fwd_q[MP1], A_t_fwd_q, MP1); /* Subframe 1 */
}
/*---------------------------------------------------------------------*
* - Decision for the switch Forward / Backward *
*---------------------------------------------------------------------*/
if(rate == G729E) {
set_lpc_modeg(speech, A_t_fwd_q, A_t_bwd, &lp_mode,
lsp_new, lsp_old, &bwd_dominant, prev_lp_mode, prev_filter,
&C_int, &glob_stat, &stat_bwd, &val_stat_bwd);
}
else {
update_bwd( &lp_mode, &bwd_dominant, &C_int, &glob_stat);
}
/* ---------------------------------- */
/* update the LSPs for the next frame */
/* ---------------------------------- */
Copy(lsp_new, lsp_old, M);
/*----------------------------------------------------------------------*
* - Find the weighted input speech w_sp[] for the whole speech frame *
*----------------------------------------------------------------------*/
if(lp_mode == 0) {
m_ap = M;
if (bwd_dominant == 0) Ap = A_t_fwd;
else Ap = A_t_fwd_q;
perc_var(gamma1, gamma2, lsf_int, lsf_new, rc_fwd);
}
else {
if (bwd_dominant == 0) {
m_ap = M;
Ap = A_t_fwd;
}
else {
m_ap = M_BWD;
Ap = A_t_bwd;
}
perc_vare(gamma1, gamma2, bwd_dominant);
}
pAp = Ap;
for (i=0; i<2; i++) {
Weight_Az(pAp, gamma1[i], m_ap, Ap1);
Weight_Az(pAp, gamma2[i], m_ap, Ap2);
Residue(m_ap, Ap1, &speech[i*L_SUBFR], &wsp[i*L_SUBFR], L_SUBFR);
Syn_filte(m_ap, Ap2, &wsp[i*L_SUBFR], &wsp[i*L_SUBFR], L_SUBFR,
&mem_w[M_BWD-m_ap], 0);
for(j=0; j<M_BWD; j++) mem_w[j] = wsp[i*L_SUBFR+L_SUBFR-M_BWD+j];
pAp += m_ap+1;
}
*ana++ = rate+ (Word16)2; /* bit rate mode */
if(lp_mode == 0) {
m_aq = M;
Aq = A_t_fwd_q;
/* update previous filter for next frame */
Copy(&Aq[MP1], prev_filter, MP1);
for(i=MP1; i <M_BWDP1; i++) prev_filter[i] = 0;
for(j=MP1; j<M_BWDP1; j++) ai_zero[j] = 0;
}
else {
m_aq = M_BWD;
Aq = A_t_bwd;
if (bwd_dominant == 0) {
for(j=MP1; j<M_BWDP1; j++) ai_zero[j] = 0;
}
/* update previous filter for next frame */
Copy(&Aq[M_BWDP1], prev_filter, M_BWDP1);
}
if (rate == G729E) *ana++ = lp_mode;
/*----------------------------------------------------------------------*
* - Find the weighted input speech w_sp[] for the whole speech frame *
* - Find the open-loop pitch delay *
*----------------------------------------------------------------------*/
if( lp_mode == 0) {
Copy(lsp_new_q, lsp_old_q, M);
Lsp_prev_update(freq_cur, freq_prev);
*ana++ = code_lsp[0];
*ana++ = code_lsp[1];
}
/* Find open loop pitch lag */
T_op = Pitch_ol(wsp, PIT_MIN, PIT_MAX, L_FRAME);
/* Range for closed loop pitch search in 1st subframe */
T0_min = sub(T_op, 3);
if (sub(T0_min,PIT_MIN)<0) {
T0_min = PIT_MIN;
}
T0_max = add(T0_min, 6);
if (sub(T0_max ,PIT_MAX)>0)
{
T0_max = PIT_MAX;
T0_min = sub(T0_max, 6);
}
/*------------------------------------------------------------------------*
* Loop for every subframe in the analysis frame *
*------------------------------------------------------------------------*
* To find the pitch and innovation parameters. The subframe size is *
* L_SUBFR and the loop is repeated 2 times. *
* - find the weighted LPC coefficients *
* - find the LPC residual signal res[] *
* - compute the target signal for pitch search *
* - compute impulse response of weighted synthesis filter (h1[]) *
* - find the closed-loop pitch parameters *
* - encode the pitch delay *
* - update the impulse response h1[] by including fixed-gain pitch *
* - find target vector for codebook search *
* - codebook search *
* - encode codebook address *
* - VQ of pitch and codebook gains *
* - find synthesis speech *
* - update states of weighting filter *
*------------------------------------------------------------------------*/
pAp = Ap; /* pointer to interpolated "unquantized"LPC parameters */
pAq = Aq; /* pointer to interpolated "quantized" LPC parameters */
i_gamma = 0;
for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) {
/*---------------------------------------------------------------*
* Find the weighted LPC coefficients for the weighting filter. *
*---------------------------------------------------------------*/
Weight_Az(pAp, gamma1[i_gamma], m_ap, Ap1);
Weight_Az(pAp, gamma2[i_gamma], m_ap, Ap2);
/*---------------------------------------------------------------*
* Compute impulse response, h1[], of weighted synthesis filter *
*---------------------------------------------------------------*/
for (i = 0; i <=m_ap; i++) ai_zero[i] = Ap1[i];
Syn_filte(m_aq, pAq, ai_zero, h1, L_SUBFR, zero, 0);
Syn_filte(m_ap, Ap2, h1, h1, L_SUBFR, zero, 0);
/*------------------------------------------------------------------------*
* *
* Find the target vector for pitch search: *
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ *
* *
* |------| res[n] *
* speech[n]---| A(z) |-------- *
* |------| | |--------| error[n] |------| *
* zero -- (-)--| 1/A(z) |-----------| W(z) |-- target *
* exc |--------| |------| *
* *
* Instead of subtracting the zero-input response of filters from *
* the weighted input speech, the above configuration is used to *
* compute the target vector. This configuration gives better performance *
* with fixed-point implementation. The memory of 1/A(z) is updated by *
* filtering (res[n]-exc[n]) through 1/A(z), or simply by subtracting *
* the synthesis speech from the input speech: *
* error[n] = speech[n] - syn[n]. *
* The memory of W(z) is updated by filtering error[n] through W(z), *
* or more simply by subtracting the filtered adaptive and fixed *
* codebook excitations from the target: *
* target[n] - gain_pit*y1[n] - gain_code*y2[n] *
* as these signals are already available. *
* *
*------------------------------------------------------------------------*/
Residue(m_aq, pAq, &speech[i_subfr], &exc[i_subfr], L_SUBFR); /* LPC residual */
for (i=0; i<L_SUBFR; i++) res2[i] = exc[i_subfr+i];
Syn_filte(m_aq, pAq, &exc[i_subfr], error, L_SUBFR,
&mem_err[M_BWD-m_aq], 0);
Residue(m_ap, Ap1, error, xn, L_SUBFR);
Syn_filte(m_ap, Ap2, xn, xn, L_SUBFR, &mem_w0[M_BWD-m_ap], 0); /* target signal xn[]*/
/*----------------------------------------------------------------------*
* Closed-loop fractional pitch search *
*----------------------------------------------------------------------*/
T0 = Pitch_fr3cp(&exc[i_subfr], xn, h1, L_SUBFR, T0_min, T0_max,
i_subfr, &T0_frac, rate);
index = Enc_lag3cp(T0, T0_frac, &T0_min, &T0_max,PIT_MIN,PIT_MAX,
i_subfr, rate);
*ana++ = index;
if ( (i_subfr == 0) && (rate != G729D) ) {
*ana = Parity_Pitch(index);
if( rate == G729E) {
*ana ^= (shr(index, 1) & 0x0001);
}
ana++;
}
/*-----------------------------------------------------------------*
* - find unity gain pitch excitation (adaptive codebook entry) *
* with fractional interpolation. *
* - find filtered pitch exc. y1[]=exc[] convolve with h1[]) *
* - compute pitch gain and limit between 0 and 1.2 *
* - update target vector for codebook search *
* - find LTP residual. *
*-----------------------------------------------------------------*/
Pred_lt_3(&exc[i_subfr], T0, T0_frac, L_SUBFR);
Convolve(&exc[i_subfr], h1, y1, L_SUBFR);
gain_pit = G_pitch(xn, y1, g_coeff, L_SUBFR);
/* clip pitch gain if taming is necessary */
taming = test_err(T0, T0_frac);
if( taming == 1){
if (sub(gain_pit, GPCLIP) > 0) {
gain_pit = GPCLIP;
}
}
/* xn2[i] = xn[i] - y1[i] * gain_pit */
for (i = 0; i < L_SUBFR; i++) {
L_temp = L_mult(y1[i], gain_pit);
L_temp = L_shl(L_temp, 1); /* gain_pit in Q14 */
xn2[i] = sub(xn[i], extract_h(L_temp));
}
/*-----------------------------------------------------*
* - Innovative codebook search. *
*-----------------------------------------------------*/
switch (rate) {
case G729: /* 8 kbit/s */
{
/* case 8 kbit/s */
index = ACELP_Codebook(xn2, h1, T0, sharp, i_subfr, code, y2, &i);
*ana++ = index; /* Positions index */
*ana++ = i; /* Signs index */
break;
}
case G729D: /* 6.4 kbit/s */
{
index = ACELP_CodebookD(xn2, h1, T0, sharp, code, y2, &i);
*ana++ = index; /* Positions index */
*ana++ = i; /* Signs index */
break;
}
case G729E: /* 11.8 kbit/s */
{
/*-----------------------------------------------------------------*
* Include fixed-gain pitch contribution into impulse resp. h[] *
*-----------------------------------------------------------------*/
pit_sharp = shl(sharp, 1); /* From Q14 to Q15 */
if(T0 < L_SUBFR) {
for (i = T0; i < L_SUBFR; i++){ /* h[i] += pitch_sharp*h[i-T0] */
h1[i] = add(h1[i], mult(h1[i-T0], pit_sharp));
}
}
/* calculate residual after long term prediction */
/* res2[i] -= exc[i+i_subfr] * gain_pit */
for (i = 0; i < L_SUBFR; i++) {
L_temp = L_mult(exc[i+i_subfr], gain_pit);
L_temp = L_shl(L_temp, 1); /* gain_pit in Q14 */
res2[i] = sub(res2[i], extract_h(L_temp));
}
if (lp_mode == 0) ACELP_10i40_35bits(xn2, res2, h1, code, y2, ana); /* Forward */
else ACELP_12i40_44bits(xn2, res2, h1, code, y2, ana); /* Backward */
ana += 5;
/*-----------------------------------------------------------------*
* Include fixed-gain pitch contribution into code[]. *
*-----------------------------------------------------------------*/
if(T0 < L_SUBFR) {
for (i = T0; i < L_SUBFR; i++) { /* code[i] += pitch_sharp*code[i-T0] */
code[i] = add(code[i], mult(code[i-T0], pit_sharp));
}
}
break;
}
default : {
printf("Unrecognized bit rate\n");
exit(-1);
}
} /* end of switch */
/*-----------------------------------------------------*
* - Quantization of gains. *
*-----------------------------------------------------*/
g_coeff_cs[0] = g_coeff[0]; /* <y1,y1> */
exp_g_coeff_cs[0] = negate(g_coeff[1]); /* Q-Format:XXX -> JPN */
g_coeff_cs[1] = negate(g_coeff[2]); /* (xn,y1) -> -2<xn,y1> */
exp_g_coeff_cs[1] = negate(add(g_coeff[3], 1)); /* Q-Format:XXX -> JPN */
Corr_xy2( xn, y1, y2, g_coeff_cs, exp_g_coeff_cs ); /* Q0 Q0 Q12 ^Qx ^Q0 */
/* g_coeff_cs[3]:exp_g_coeff_cs[3] = <y2,y2> */
/* g_coeff_cs[4]:exp_g_coeff_cs[4] = -2<xn,y2> */
/* g_coeff_cs[5]:exp_g_coeff_cs[5] = 2<y1,y2> */
if (rate == G729D)
index = Qua_gain_6k(code, g_coeff_cs, exp_g_coeff_cs, L_SUBFR,
&gain_pit, &gain_code, taming, past_qua_en);
else
index = Qua_gain_8k(code, g_coeff_cs, exp_g_coeff_cs, L_SUBFR,
&gain_pit, &gain_code, taming, past_qua_en);
*ana++ = index;
/*------------------------------------------------------------*
* - Update pitch sharpening "sharp" with quantized gain_pit *
*------------------------------------------------------------*/
sharp = gain_pit;
if (sub(sharp, SHARPMAX) > 0) sharp = SHARPMAX;
else {
if (sub(sharp, SHARPMIN) < 0) sharp = SHARPMIN;
}
/*------------------------------------------------------*
* - Find the total excitation *
* - find synthesis speech corresponding to exc[] *
* - update filters memories for finding the target *
* vector in the next subframe *
* (update error[-m..-1] and mem_w_err[]) *
* update error function for taming process *
*------------------------------------------------------*/
for (i = 0; i < L_SUBFR; i++) {
/* exc[i] = gain_pit*exc[i] + gain_code*code[i]; */
/* exc[i] in Q0 gain_pit in Q14 */
/* code[i] in Q13 gain_cod in Q1 */
L_temp = L_mult(exc[i+i_subfr], gain_pit);
L_temp = L_mac(L_temp, code[i], gain_code);
L_temp = L_shl(L_temp, 1);
exc[i+i_subfr] = round(L_temp);
}
update_exc_err(gain_pit, T0);
Syn_filte(m_aq, pAq, &exc[i_subfr], &synth_ptr[i_subfr], L_SUBFR,
&mem_syn[M_BWD-m_aq], 0);
for(j=0; j<M_BWD; j++) mem_syn[j] = synth_ptr[i_subfr+L_SUBFR-M_BWD+j];
for (i = L_SUBFR-M_BWD, j = 0; i < L_SUBFR; i++, j++) {
mem_err[j] = sub(speech[i_subfr+i], synth_ptr[i_subfr+i]);
temp = extract_h(L_shl( L_mult(y1[i], gain_pit), 1) );
k = extract_h(L_shl( L_mult(y2[i], gain_code), 2) );
mem_w0[j] = sub(xn[i], add(temp, k));
}
pAp += m_ap+1;
pAq += m_aq+1;
i_gamma = add(i_gamma,1);
}
/*--------------------------------------------------*
* Update signal for next frame. *
* -> shift to the left by L_FRAME: *
* speech[], wsp[] and exc[] *
*--------------------------------------------------*/
Copy(&old_speech[L_FRAME], &old_speech[0], L_TOTAL-L_FRAME);
Copy(&old_wsp[L_FRAME], &old_wsp[0], PIT_MAX);
Copy(&old_exc[L_FRAME], &old_exc[0], PIT_MAX+L_INTERPOL);
prev_lp_mode = lp_mode;
return;
}
void Decod_ld8c (
Word16 parm[], /* (i) : vector of synthesis parameters
parm[0] = bad frame indicator (bfi) */
Word16 voicing, /* (i) : voicing decision from previous frame */
Word16 synth_buf[], /* (i/o) : synthesis speech */
Word16 Az_dec[], /* (o) : decoded LP filter in 2 subframes */
Word16 *T0_first, /* (o) : decoded pitch lag in first subframe */
Word16 *bwd_dominant, /* (o) : */
Word16 *m_pst, /* (o) : LPC order for postfilter */
Word16 *Vad
)
{
/* Scalars */
Word16 i, j, i_subfr;
Word16 T0, T0_frac, index;
Word16 bfi;
Word16 lp_mode; /* Backward / Forward mode indication */
Word16 g_p, g_c; /* fixed and adaptive codebook gain */
Word16 bad_pitch; /* bad pitch indicator */
Word16 tmp, tmp1, tmp2;
Word16 sat_filter;
Word32 L_temp;
Word32 energy;
Word16 temp;
/* Tables */
Word16 A_t_bwd[2*M_BWDP1]; /* LPC Backward filter */
Word16 A_t_fwd[2*MP1]; /* LPC Forward filter */
Word16 rc_bwd[M_BWD]; /* LPC backward reflection coefficients */
Word32 r_bwd[M_BWDP1]; /* Autocorrelations (backward) */
Word16 r_l_bwd[M_BWDP1]; /* Autocorrelations low (backward) */
Word16 r_h_bwd[M_BWDP1]; /* Autocorrelations high (backward) */
Word16 lsp_new[M]; /* LSPs */
Word16 code[L_SUBFR]; /* ACELP codevector */
Word16 *pA_t; /* Pointer on A_t */
Word16 stationnary;
Word16 m_aq;
Word16 *synth;
Word16 exc_phdisp[L_SUBFR]; /* excitation after phase dispersion */
extern Flag Overflow;
Word16 rate;
/* for G.729B */
Word16 ftyp;
Word16 lsfq_mem[MA_NP][M];
synth = synth_buf + MEM_SYN_BWD;
/* Test bad frame indicator (bfi) */
bfi = *parm++;
/* Test frame type */
ftyp = *parm++;
if(bfi == 1) {
ftyp = past_ftyp;
if(ftyp == 1) ftyp = 0;
if(ftyp > 2) { /* G.729 maintenance */
if(ftyp == 3) parm[4] = 1;
else {
if(prev_lp_mode == 0) parm[5] = 1;
else parm[3] = 1;
}
}
parm[-1] = ftyp;
}
*Vad = ftyp;
rate = ftyp - (Word16)2;
/* Decoding the Backward/Forward LPC decision */
/* ------------------------------------------ */
if( rate != G729E) lp_mode = 0;
else {
if (bfi != 0) {
lp_mode = prev_lp_mode; /* Frame erased => mode = previous mode */
*parm++ = lp_mode;
}
else {
lp_mode = *parm++;
}
if(prev_bfi != 0) voicing = prev_voicing;
}
if( bfi == 0) {
c_muting = 32767;
count_bfi = 0;
}
/* -------------------- */
/* Backward LP analysis */
/* -------------------- */
if (rate == G729E) {
/* LPC recursive Window as in G728 */
autocorr_hyb_window(synth_buf, r_bwd, rexp); /* Autocorrelations */
Lag_window_bwd(r_bwd, r_h_bwd, r_l_bwd); /* Lag windowing */
/* Fixed Point Levinson (as in G729) */
Levinsoncp(M_BWD, r_h_bwd, r_l_bwd, &A_t_bwd[M_BWDP1], rc_bwd,
old_A_bwd, old_rc_bwd, &temp);
/* Tests saturation of A_t_bwd */
sat_filter = 0;
for (i=M_BWDP1; i<2*M_BWDP1; i++) if (A_t_bwd[i] >= 32767) sat_filter = 1;
if (sat_filter == 1) Copy(A_t_bwd_mem, &A_t_bwd[M_BWDP1], M_BWDP1);
else Copy(&A_t_bwd[M_BWDP1], A_t_bwd_mem, M_BWDP1);
/* Additional bandwidth expansion on backward filter */
Weight_Az(&A_t_bwd[M_BWDP1], GAMMA_BWD, M_BWD, &A_t_bwd[M_BWDP1]);
}
/*--------------------------------------------------*
* Update synthesis signal for next frame. *
*--------------------------------------------------*/
Copy(&synth_buf[L_FRAME], &synth_buf[0], MEM_SYN_BWD);
if(lp_mode == 1) {
if ((C_fe_fix != 0)) {
/* Interpolation of the backward filter after a bad frame */
/* A_t_bwd(z) = C_fe . A_bwd_mem(z) + (1 - C_fe) . A_t_bwd(z) */
/* ---------------------------------------------------------- */
tmp = sub(4096, C_fe_fix);
pA_t = A_t_bwd + M_BWDP1;
for (i=0; i<M_BWDP1; i++) {
L_temp = L_mult(pA_t[i], tmp);
L_temp = L_shr(L_temp, 13);
tmp1 = extract_l(L_temp);
L_temp = L_mult(A_bwd_mem[i], C_fe_fix);
L_temp = L_shr(L_temp, 13);
tmp2 = extract_l(L_temp);
pA_t[i] = add(tmp1, tmp2);
}
}
}
/* Memorize the last good backward filter when the frame is erased */
if ((bfi != 0)&&(prev_bfi == 0) && (past_ftyp >3))
for (i=0; i<M_BWDP1; i++) A_bwd_mem[i] = A_t_bwd[i+M_BWDP1];
/* for G.729B */
/* Processing non active frames (SID & not transmitted: ftyp = 1 or 0) */
if(ftyp < 2) {
/* get_decfreq_prev(lsfq_mem); */
for (i=0; i<MA_NP; i++)
Copy(&freq_prev[i][0], &lsfq_mem[i][0], M);
Dec_cng(past_ftyp, sid_sav, sh_sid_sav, &parm[-1], exc, lsp_old,
A_t_fwd, &seed, lsfq_mem);
/* update_decfreq_prev(lsfq_mem); */
for (i=0; i<MA_NP; i++)
Copy(&lsfq_mem[i][0], &freq_prev[i][0], M);
pA_t = A_t_fwd;
for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) {
Overflow = 0;
Syn_filte(M, pA_t, &exc[i_subfr], &synth[i_subfr], L_SUBFR,
&mem_syn[M_BWD-M], 0);
if(Overflow != 0) {
/* In case of overflow in the synthesis */
/* -> Scale down vector exc[] and redo synthesis */
for(i=0; i<PIT_MAX+L_INTERPOL+L_FRAME; i++)
old_exc[i] = shr(old_exc[i], 2);
Syn_filte(M, pA_t, &exc[i_subfr], &synth[i_subfr], L_SUBFR,
&mem_syn[M_BWD-M], 0);
}
Copy(&synth[i_subfr+L_SUBFR-M_BWD], mem_syn, M_BWD);
pA_t += MP1;
}
*T0_first = prev_T0;
sharp = SHARPMIN;
C_int = 4506;
/* for gain decoding in case of frame erasure */
stat_bwd = 0;
stationnary = 0;
/* for pitch tracking in case of frame erasure */
stat_pitch = 0;
/* update the previous filter for the next frame */
Copy(&A_t_fwd[MP1], prev_filter, MP1);
for(i=MP1; i<M_BWDP1; i++) prev_filter[i] = 0;
}
else {
/***************************/
/* Processing active frame */
/***************************/
seed = INIT_SEED;
/* ---------------------------- */
/* LPC decoding in forward mode */
/* ---------------------------- */
if (lp_mode == 0) {
/* Decode the LSPs */
D_lspe(parm, lsp_new, bfi, freq_prev, prev_lsp, &prev_ma);
parm += 2;
if( prev_lp_mode == 0) { /* Interpolation of LPC for the 2 subframes */
Int_qlpc(lsp_old, lsp_new, A_t_fwd);
}
else {
/* no interpolation */
Lsp_Az(lsp_new, A_t_fwd); /* Subframe 1*/
Copy(A_t_fwd, &A_t_fwd[MP1], MP1); /* Subframe 2 */
}
/* update the LSFs for the next frame */
Copy(lsp_new, lsp_old, M);
C_int = 4506;
pA_t = A_t_fwd;
m_aq = M;
/* update the previous filter for the next frame */
Copy(&A_t_fwd[MP1], prev_filter, MP1);
for(i=MP1; i<M_BWDP1; i++) prev_filter[i] = 0;
}
else {
Int_bwd(A_t_bwd, prev_filter, &C_int);
pA_t = A_t_bwd;
m_aq = M_BWD;
/* update the previous filter for the next frame */
Copy(&A_t_bwd[M_BWDP1], prev_filter, M_BWDP1);
}
/*------------------------------------------------------------------------*
* Loop for every subframe in the analysis frame *
*------------------------------------------------------------------------*
* The subframe size is L_SUBFR and the loop is repeated L_FRAME/L_SUBFR *
* times *
* - decode the pitch delay *
* - decode algebraic code *
* - decode pitch and codebook gains *
* - find the excitation and compute synthesis speech *
*------------------------------------------------------------------------*/
for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) {
index = *parm++; /* pitch index */
if(i_subfr == 0) {
if (rate == G729D)
i = 0; /* no pitch parity at 6.4 kb/s */
else
i = *parm++; /* get parity check result */
bad_pitch = add(bfi, i);
if( bad_pitch == 0) {
Dec_lag3cp(index, PIT_MIN, PIT_MAX, i_subfr, &T0, &T0_frac,rate);
prev_T0 = T0;
prev_T0_frac = T0_frac;
}
else { /* Bad frame, or parity error */
if (bfi == 0) printf(" ! Wrong Pitch 1st subfr. ! ");
T0 = prev_T0;
if (rate == G729E) {
T0_frac = prev_T0_frac;
}
else {
T0_frac = 0;
prev_T0 = add( prev_T0, 1);
if( sub(prev_T0, PIT_MAX) > 0) {
prev_T0 = PIT_MAX;
}
}
}
*T0_first = T0; /* If first frame */
}
else { /* second subframe */
if( bfi == 0) {
Dec_lag3cp(index, PIT_MIN, PIT_MAX, i_subfr, &T0, &T0_frac, rate);
prev_T0 = T0;
prev_T0_frac = T0_frac;
}
else {
T0 = prev_T0;
if (rate == G729E) {
T0_frac = prev_T0_frac;
}
else {
T0_frac = 0;
prev_T0 = add( prev_T0, 1);
if( sub(prev_T0, PIT_MAX) > 0) prev_T0 = PIT_MAX;
}
}
}
/*-------------------------------------------------*
* - Find the adaptive codebook vector. *
*-------------------------------------------------*/
Pred_lt_3(&exc[i_subfr], T0, T0_frac, L_SUBFR);
/* --------------------------------- */
/* pitch tracking for frame erasures */
/* --------------------------------- */
if( rate == G729E) {
track_pit(&prev_T0, &prev_T0_frac, &prev_pitch, &stat_pitch,
&pitch_sta, &frac_sta);
}
else {
i = prev_T0;
j = prev_T0_frac;
track_pit(&i, &j, &prev_pitch, &stat_pitch,
&pitch_sta, &frac_sta);
}
/*-------------------------------------------------------*
* - Decode innovative codebook. *
*-------------------------------------------------------*/
if(bfi != 0) { /* Bad frame */
parm[0] = Random_g729cp(&seed_fer);
parm[1] = Random_g729cp(&seed_fer);
if (rate == G729E) {
parm[2] = Random_g729cp(&seed_fer);
parm[3] = Random_g729cp(&seed_fer);
parm[4] = Random_g729cp(&seed_fer);
}
}
stationnary = 0; /* to avoid visual warning */
if (rate == G729) {
/* case 8 kbps */
Decod_ACELP(parm[1], parm[0], code);
parm += 2;
/* for gain decoding in case of frame erasure */
stat_bwd = 0;
stationnary = 0;
}
else if (rate == G729D) {
/* case 6.4 kbps */
Decod_ACELP64(parm[1], parm[0], code);
parm += 2;
/* for gain decoding in case of frame erasure */
stat_bwd = 0;
stationnary = 0;
}
else if (rate == G729E) {
/* case 11.8 kbps */
if (lp_mode == 0) {
Dec_ACELP_10i40_35bits(parm, code);
/* for gain decoding in case of frame erasure */
stat_bwd = 0;
stationnary = 0;
}
else {
Dec_ACELP_12i40_44bits(parm, code);
/* for gain decoding in case of frame erasure */
stat_bwd = add(stat_bwd,1);
if (sub(stat_bwd,30) >= 0) {
stationnary = 1;
stat_bwd = 30;
}
else stationnary = 0;
}
parm += 5;
}
/*-------------------------------------------------------*
* - Add the fixed-gain pitch contribution to code[]. *
*-------------------------------------------------------*/
j = shl(sharp, 1); /* From Q14 to Q15 */
if(sub(T0, L_SUBFR) <0 ) {
for (i = T0; i < L_SUBFR; i++) {
code[i] = add(code[i], mult(code[i-T0], j));
}
}
/*-------------------------------------------------*
* - Decode pitch and codebook gains. *
*-------------------------------------------------*/
index = *parm++; /* index of energy VQ */
if (rate == G729D)
Dec_gain_6k(index, code, L_SUBFR, bfi, &gain_pitch, &gain_code);
else
Dec_gaine(index, code, L_SUBFR, bfi, &gain_pitch, &gain_code, rate,
gain_pit_mem, gain_cod_mem, &c_muting, count_bfi, stationnary);
/*-------------------------------------------------------------*
* - Update previous gains
*-------------------------------------------------------------*/
gain_pit_mem = gain_pitch;
gain_cod_mem = gain_code;
/*-------------------------------------------------------------*
* - Update pitch sharpening "sharp" with quantized gain_pitch *
*-------------------------------------------------------------*/
sharp = gain_pitch;
if (sub(sharp, SHARPMAX) > 0) sharp = SHARPMAX;
if (sub(sharp, SHARPMIN) < 0) sharp = SHARPMIN;
/*-------------------------------------------------------*
* - Find the total excitation. *
* - Find synthesis speech corresponding to exc[]. *
*-------------------------------------------------------*/
if(bfi != 0) { /* Bad frame */
count_bfi = add(count_bfi,1);
if (voicing == 0 ) {
g_p = 0;
g_c = gain_code;
}
else {
g_p = gain_pitch;
g_c = 0;
}
}
else {
g_p = gain_pitch;
g_c = gain_code;
}
for (i = 0; i < L_SUBFR; i++) {
/* exc[i] = g_p*exc[i] + g_c*code[i]; */
/* exc[i] in Q0 g_p in Q14 */
/* code[i] in Q13 g_code in Q1 */
L_temp = L_mult(exc[i+i_subfr], g_p);
L_temp = L_mac(L_temp, code[i], g_c);
L_temp = L_shl(L_temp, 1);
exc[i+i_subfr] = round(L_temp);
}
/* Test whether synthesis yields overflow or not */
Overflow = 0;
Syn_filte(m_aq, pA_t, &exc[i_subfr], &synth[i_subfr], L_SUBFR,
&mem_syn[M_BWD-m_aq], 0);
/* In case of overflow in the synthesis */
/* -> Scale down vector exc[] and redo synthesis */
if(Overflow != 0) {
for(i=0; i<PIT_MAX+L_INTERPOL+L_FRAME; i++) old_exc[i] = shr(old_exc[i], 2);
}
if (rate == G729D) {
PhDisp(&exc[i_subfr], exc_phdisp, gain_code, gain_pitch, code);
Syn_filte(m_aq, pA_t, exc_phdisp, &synth[i_subfr], L_SUBFR,
&mem_syn[M_BWD-m_aq], 0);
}
else {
Syn_filte(m_aq, pA_t, &exc[i_subfr], &synth[i_subfr], L_SUBFR,
&mem_syn[M_BWD-m_aq], 0);
/* Updates state machine for phase dispersion in
6.4 kbps mode, if running at other rate */
Update_PhDisp(gain_pitch, gain_code);
}
pA_t += m_aq+1; /* interpolated LPC parameters for next subframe */
Copy(&synth[i_subfr+L_SUBFR-M_BWD], mem_syn, M_BWD);
}
}
/*------------*
* For G729b
*-----------*/
if(bfi == 0) {
L_temp = 0L;
for(i=0; i<L_FRAME; i++) {
L_temp = L_mac(L_temp, exc[i], exc[i]);
} /* may overflow => last level of SID quantizer */
sh_sid_sav = norm_l(L_temp);
sid_sav = round(L_shl(L_temp, sh_sid_sav));
sh_sid_sav = sub(16, sh_sid_sav);
}
past_ftyp = ftyp;
/*------------*
* For G729E
*-----------*/
energy = ener_dB(synth, L_FRAME);
if (energy >= 8192) tst_bwd_dominant(bwd_dominant, lp_mode);
/*--------------------------------------------------*
* Update signal for next frame. *
* -> shift to the left by L_FRAME exc[] *
*--------------------------------------------------*/
Copy(&old_exc[L_FRAME], &old_exc[0], PIT_MAX+L_INTERPOL);
if( lp_mode == 0) {
Copy(A_t_fwd, Az_dec, 2*MP1);
*m_pst = M;
}
else {
Copy(A_t_bwd, Az_dec, 2*M_BWDP1);
*m_pst = M_BWD;
}
prev_bfi = bfi;
prev_lp_mode = lp_mode;
prev_voicing = voicing;
if (bfi != 0) C_fe_fix = 4096;
else {
if (lp_mode == 0) C_fe_fix = 0;
else {
if (*bwd_dominant == 1) C_fe_fix = sub(C_fe_fix, 410);
else C_fe_fix = sub(C_fe_fix, 2048);
if (C_fe_fix < 0) C_fe_fix= 0;
}
}
return;
}
/*----------------------------------------------------------------------------
* Post - adaptive postfilter main function
*----------------------------------------------------------------------------
*/
void Poste(
Word16 t0, /* input : pitch delay given by coder */
Word16 *signal_ptr, /* input : input signal (pointer to current subframe */
Word16 *coeff, /* input : LPC coefficients for current subframe */
Word16 *sig_out, /* output: postfiltered output */
Word16 *vo, /* output: voicing decision 0 = uv, > 0 delay */
Word16 gamma1, /* input: short term postfilt. den. weighting factor*/
Word16 gamma2, /* input: short term postfilt. num. weighting factor*/
Word16 gamma_harm, /* input: long term postfilter weighting factor*/
Word16 long_h_st, /* input: impulse response length*/
Word16 m_pst, /* input: LPC order */
Word16 Vad
)
{
/* Local variables and arrays */
Word16 apond1[M_BWDP1]; /* s.t. denominator coeff. */
Word16 sig_ltp[L_SUBFRP1]; /* H0 output signal */
Word16 *sig_ltp_ptr;
Word16 parcor0;
/* Compute weighted LPC coefficients */
Weight_Az(coeff, gamma1, m_pst, apond1);
Weight_Az(coeff, gamma2, m_pst, apond2);
Set_zero(&apond2[m_pst+1], (Word16)(M_BWD-m_pst));
/* Compute A(gamma2) residual */
Residue(m_pst, apond2, signal_ptr, res2_ptr, L_SUBFR);
/* Harmonic filtering */
sig_ltp_ptr = sig_ltp + 1;
if (sub(Vad,1) > 0)
pst_ltpe(t0, res2_ptr, sig_ltp_ptr, vo, gamma_harm);
else {
*vo = 0;
Copy(res2_ptr, sig_ltp_ptr, L_SUBFR);
}
/* Save last output of 1/A(gamma1) */
/* (from preceding subframe) */
sig_ltp[0] = *ptr_mem_stp;
/* Controls short term pst filter gain and compute parcor0 */
calc_st_filte(apond2, apond1, &parcor0, sig_ltp_ptr, long_h_st, m_pst);
/* 1/A(gamma1) filtering, mem_stp is updated */
Syn_filte(m_pst, apond1, sig_ltp_ptr, sig_ltp_ptr, L_SUBFR,
&mem_stp[M_BWD-m_pst], 0);
Copy(&sig_ltp_ptr[L_SUBFR-M_BWD], mem_stp, M_BWD);
/* Tilt filtering */
filt_mu(sig_ltp, sig_out, parcor0);
/* Gain control */
scale_st(signal_ptr, sig_out, &gain_prec);
/**** Update for next subframe */
Copy(&res2[L_SUBFR], &res2[0], MEM_RES2);
return;
}
