void decod_ld8a(struct dec_state_t * state, int parm[], /* (i) : vector of synthesis parameters parm[0] = bad frame indicator (bfi) */ GFLOAT synth[], /* (o) : synthesis speech */ GFLOAT A_t[], /* (o) : decoded LP filter in 2 subframes */ int *T2, /* (o) : decoded pitch lag in 2 subframes */ int *Vad /* (o) : decoded frame type */ ) { GFLOAT *Az; /* Pointer on A_t */ GFLOAT lsp_new[M]; /* Decoded LSP's */ GFLOAT code[L_SUBFR]; /* ACELP codevector */ /* Scalars */ int i, i_subfr; int t0, t0_frac, index; int bfi, bad_pitch; /* for G.729B */ int ftyp; GFLOAT lsfq_mem[MA_NP][M]; /* Test bad frame indicator (bfi) */ bfi = *parm++; /* for G.729B */ ftyp = *parm; if (bfi) { if(state->past_ftyp == 1) ftyp = 1; else ftyp = 0; *parm = ftyp; /* modification introduced in version V1.3 */ } *Vad = ftyp; /* Processing non active frames (SID & not transmitted) */ if(ftyp != 1) { get_freq_prev((const GFLOAT (*)[M]) state->lsp_s.freq_prev, lsfq_mem); dec_cng(&state->cng_s, state->past_ftyp, state->sid_sav, parm, state->exc, state->lsp_old, A_t, &state->seed, lsfq_mem); update_freq_prev(state->lsp_s.freq_prev, (const GFLOAT (*)[M]) lsfq_mem); Az = A_t; for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) { syn_filt(Az, &state->exc[i_subfr], &synth[i_subfr], L_SUBFR, state->mem_syn, 0); copy(&synth[i_subfr+L_SUBFR-M], state->mem_syn, M); Az += MP1; *T2++ = state->old_t0; } state->sharp = SHARPMIN; } else /* Processing active frame */ { state->seed = INIT_SEED; parm++; /* Decode the LSPs */ d_lsp(&state->lsp_s, parm, lsp_new, bfi+state->bad_lsf ); parm += 2; /* Advance synthesis parameters pointer */ /* Note: "bad_lsf" is introduce in case the standard is used with channel protection. */ /* Interpolation of LPC for the 2 subframes */ int_qlpc(state->lsp_old, lsp_new, A_t); /* update the LSFs for the next frame */ copy(lsp_new, state->lsp_old, M); /*------------------------------------------------------------------------* * 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 * *------------------------------------------------------------------------*/ Az = A_t; /* pointer to interpolated LPC parameters */ for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) { /*-------------------------------------------------* * - Find the adaptive codebook vector. * *--------------------------------------------------*/ index = *parm++; /* pitch index */ if (i_subfr == 0) { i = *parm++; /* get parity check result */ bad_pitch = bfi + i; if( bad_pitch == 0) { dec_lag3(index, PIT_MIN, PIT_MAX, i_subfr, &t0, &t0_frac); state->old_t0 = t0; } else /* Bad frame, or parity error */ { t0 = state->old_t0; t0_frac = 0; state->old_t0++; if( (state->old_t0 - PIT_MAX) > 0) state->old_t0 = PIT_MAX; } } else /* second subframe */ { if( bfi == 0) { dec_lag3(index, PIT_MIN, PIT_MAX, i_subfr, &t0, &t0_frac); state->old_t0 = t0; } else { t0 = state->old_t0; t0_frac = 0; state->old_t0++; if( (state->old_t0 - PIT_MAX) > 0) state->old_t0 = PIT_MAX; } } *T2++ = t0; /*-------------------------------------------------* * - Find the adaptive codebook vector. * *-------------------------------------------------*/ pred_lt_3(&state->exc[i_subfr], t0, t0_frac, L_SUBFR); /*-------------------------------------------------------* * - Decode innovative codebook. * * - Add the fixed-gain pitch contribution to code[]. * *-------------------------------------------------------*/ if(bfi != 0) /* Bad frame */ { parm[0] = random_g729(&state->seed_fer) & (INT16)0x1fff; /* 13 bits random */ parm[1] = random_g729(&state->seed_fer) & (INT16)0x000f; /* 4 bits random */ } decod_ACELP(parm[1], parm[0], code); parm +=2; for (i = t0; i < L_SUBFR; i++) code[i] += state->sharp * code[i-t0]; /*-------------------------------------------------* * - Decode pitch and codebook gains. * *-------------------------------------------------*/ index = *parm++; /* index of energy VQ */ dec_gain(&state->gain_s, index, code, L_SUBFR, bfi, &state->gain_pitch, &state->gain_code); /*-------------------------------------------------------------* * - Update pitch sharpening "sharp" with quantized gain_pitch * *-------------------------------------------------------------*/ state->sharp = state->gain_pitch; if (state->sharp > SHARPMAX) state->sharp = SHARPMAX; if (state->sharp < SHARPMIN) state->sharp = SHARPMIN; /*-------------------------------------------------------* * - Find the total excitation. * * - Find synthesis speech corresponding to exc[]. * *-------------------------------------------------------*/ for (i = 0; i < L_SUBFR; i++) state->exc[i+i_subfr] = state->gain_pitch*state->exc[i+i_subfr] + state->gain_code*code[i]; syn_filt(Az, &state->exc[i_subfr], &synth[i_subfr], L_SUBFR, state->mem_syn, 1); Az += MP1; /* interpolated LPC parameters for next subframe */ } } /*------------* * For G729b *-----------*/ if (bfi == 0) { state->sid_sav = (F)0.0; for (i=0; i<L_FRAME; i++) state->sid_sav += state->exc[i] * state->exc[i]; } state->past_ftyp = ftyp; /*--------------------------------------------------* * Update signal for next frame. * * -> shift to the left by L_FRAME exc[] * *--------------------------------------------------*/ copy(&state->old_exc[L_FRAME], &state->old_exc[0], PIT_MAX+L_INTERPOL); }
/*-------------------------------------------------------------------------- * decod_ld8k - decoder *-------------------------------------------------------------------------- */ void decod_ld8k( int parm[], /* input : synthesis parameters (parm[0] = bfi) */ int voicing, /* input : voicing decision from previous frame */ FLOAT synth[], /* output: synthesized speech */ FLOAT A_t[], /* output: two sets of A(z) coefficients length=2*MP1 */ int *t0_first /* output: integer delay of first subframe */ ) { FLOAT *Az; /* Pointer to A_t (LPC coefficients) */ FLOAT lsp_new[M]; /* LSPs */ FLOAT code[L_SUBFR]; /* algebraic codevector */ /* Scalars */ int i, i_subfr; int t0, t0_frac, index; int bfi; int bad_pitch; /* Test bad frame indicator (bfi) */ bfi = *parm++; /* Decode the LSPs */ d_lsp(parm, lsp_new, bfi); parm += 2; /* Advance synthesis parameters pointer */ /* Interpolation of LPC for the 2 subframes */ int_qlpc(lsp_old, lsp_new, A_t); /* update the LSFs for the next frame */ copy(lsp_new, lsp_old, M); /*------------------------------------------------------------------------* * 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 * *------------------------------------------------------------------------*/ Az = A_t; /* pointer to interpolated LPC parameters */ for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) { index = *parm++; /* pitch index */ if (i_subfr == 0) { /* if first subframe */ i = *parm++; /* get parity check result */ bad_pitch = bfi+ i; if( bad_pitch == 0) { dec_lag3(index, PIT_MIN, PIT_MAX, i_subfr, &t0, &t0_frac); old_t0 = t0; } else /* Bad frame, or parity error */ { t0 = old_t0; t0_frac = 0; old_t0++; if( old_t0> PIT_MAX) { old_t0 = PIT_MAX; } } *t0_first = t0; /* If first frame */ } else /* second subframe */ { if( bfi == 0) { dec_lag3(index, PIT_MIN, PIT_MAX, i_subfr, &t0, &t0_frac); old_t0 = t0; } else { t0 = old_t0; t0_frac = 0; old_t0++; if( old_t0 >PIT_MAX) { old_t0 = PIT_MAX; } } } /*-------------------------------------------------* * - Find the adaptive codebook vector. * *--------------------------------------------------*/ pred_lt_3(&exc[i_subfr], t0, t0_frac, L_SUBFR); /*-------------------------------------------------------* * - Decode innovative codebook. * * - Add the fixed-gain pitch contribution to code[]. * *-------------------------------------------------------*/ if(bfi != 0) { /* Bad Frame Error Concealment */ parm[0] = (int) (random_g729() & 0x1fff); /* 13 bits random*/ parm[1]= (int) (random_g729() & 0x000f); /* 4 bits random */ } decod_ACELP(parm[1], parm[0], code); parm +=2; for (i = t0; i < L_SUBFR; i++) code[i] += sharp * code[i-t0]; /*-------------------------------------------------* * - Decode pitch and codebook gains. * *-------------------------------------------------*/ index = *parm++; /* index of energy VQ */ dec_gain(index, code, L_SUBFR, bfi, &gain_pitch, &gain_code); /*-------------------------------------------------------------* * - Update pitch sharpening "sharp" with quantized gain_pitch * *-------------------------------------------------------------*/ sharp = gain_pitch; if (sharp > SHARPMAX) sharp = SHARPMAX; if (sharp < SHARPMIN) sharp = SHARPMIN; /*-------------------------------------------------------* * - Find the total excitation. * *-------------------------------------------------------*/ if(bfi != 0 ) { if(voicing == 0) { /* for unvoiced frame */ for (i = 0; i < L_SUBFR; i++) { exc[i+i_subfr] = gain_code*code[i]; } } else { /* for voiced frame */ for (i = 0; i < L_SUBFR; i++) { exc[i+i_subfr] = gain_pitch*exc[i+i_subfr]; } } } else { /* No frame errors */ for (i = 0; i < L_SUBFR; i++) { exc[i+i_subfr] = gain_pitch*exc[i+i_subfr] + gain_code*code[i]; } } /*-------------------------------------------------------* * - Find synthesis speech corresponding to exc[]. * *-------------------------------------------------------*/ syn_filt(Az, &exc[i_subfr], &synth[i_subfr], L_SUBFR, mem_syn, 1); Az += MP1; /* interpolated LPC parameters for next subframe */ } /*--------------------------------------------------* * 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); return; }
void coder_ld8a( int ana[] /* output: analysis parameters */ ) { /* LPC coefficients */ FLOAT Aq_t[(MP1)*2]; /* A(z) quantized for the 2 subframes */ FLOAT Ap_t[(MP1)*2]; /* A(z) with spectral expansion */ FLOAT *Aq, *Ap; /* Pointer on Aq_t and Ap_t */ /* Other vectors */ FLOAT h1[L_SUBFR]; /* Impulse response h1[] */ FLOAT xn[L_SUBFR]; /* Target vector for pitch search */ FLOAT xn2[L_SUBFR]; /* Target vector for codebook search */ FLOAT code[L_SUBFR]; /* Fixed codebook excitation */ FLOAT y1[L_SUBFR]; /* Filtered adaptive excitation */ FLOAT y2[L_SUBFR]; /* Filtered fixed codebook excitation */ FLOAT g_coeff[5]; /* Correlations between xn, y1, & y2: <y1,y1>, <xn,y1>, <y2,y2>, <xn,y2>,<y1,y2>*/ /* Scalars */ int i, j, i_subfr; int T_op, T0, T0_min, T0_max, T0_frac; int index; FLOAT gain_pit, gain_code; int taming; /*------------------------------------------------------------------------* * - 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) * *------------------------------------------------------------------------*/ { /* Temporary vectors */ FLOAT r[MP1]; /* Autocorrelations */ FLOAT rc[M]; /* Reflexion coefficients */ FLOAT lsp_new[M]; /* lsp coefficients */ FLOAT lsp_new_q[M]; /* Quantized lsp coeff. */ /* LP analysis */ autocorr(p_window, M, r); /* Autocorrelations */ lag_window(M, r); /* Lag windowing */ levinson(r, Ap_t, rc); /* Levinson Durbin */ az_lsp(Ap_t, lsp_new, lsp_old); /* Convert A(z) to lsp */ /* LSP quantization */ qua_lsp(lsp_new, lsp_new_q, ana); ana += 2; /* Advance analysis parameters pointer */ /*--------------------------------------------------------------------* * Find interpolated LPC parameters in all subframes * * The interpolated parameters are in array Aq_t[]. * *--------------------------------------------------------------------*/ int_qlpc(lsp_old_q, lsp_new_q, Aq_t); /* Compute A(z/gamma) */ weight_az(&Aq_t[0], GAMMA1, M, &Ap_t[0]); weight_az(&Aq_t[MP1], GAMMA1, M, &Ap_t[MP1]); /* update the LSPs for the next frame */ copy(lsp_new, lsp_old, M); copy(lsp_new_q, lsp_old_q, M); } /*----------------------------------------------------------------------* * - Find the weighted input speech w_sp[] for the whole speech frame * * - Find the open-loop pitch delay for the whole speech frame * * - Set the range for searching closed-loop pitch in 1st subframe * *----------------------------------------------------------------------*/ residu(&Aq_t[0], &speech[0], &exc[0], L_SUBFR); residu(&Aq_t[MP1], &speech[L_SUBFR], &exc[L_SUBFR], L_SUBFR); { FLOAT Ap1[MP1]; Ap = Ap_t; Ap1[0] = (F)1.0; for(i=1; i<=M; i++) Ap1[i] = Ap[i] - (F)0.7 * Ap[i-1]; syn_filt(Ap1, &exc[0], &wsp[0], L_SUBFR, mem_w, 1); Ap += MP1; for(i=1; i<=M; i++) Ap1[i] = Ap[i] - (F)0.7 * Ap[i-1]; syn_filt(Ap1, &exc[L_SUBFR], &wsp[L_SUBFR], L_SUBFR, mem_w, 1); } /* Find open loop pitch lag for whole speech frame */ T_op = pitch_ol_fast(wsp, L_FRAME); /* Range for closed loop pitch search in 1st subframe */ T0_min = T_op - 3; if (T0_min < PIT_MIN) T0_min = PIT_MIN; T0_max = T0_min + 6; if (T0_max > PIT_MAX) { T0_max = PIT_MAX; T0_min = 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 L_FRAME/L_SUBFR times. * * - find the weighted LPC coefficients * * - find the LPC residual signal * * - 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 * * - find target vector for codebook search * * - codebook search * * - VQ of pitch and codebook gains * * - update states of weighting filter * *------------------------------------------------------------------------*/ Aq = Aq_t; /* pointer to interpolated quantized LPC parameters */ Ap = Ap_t; /* pointer to weighted LPC coefficients */ for (i_subfr = 0; i_subfr < L_FRAME; i_subfr += L_SUBFR) { /*---------------------------------------------------------------* * Compute impulse response, h1[], of weighted synthesis filter * *---------------------------------------------------------------*/ h1[0] = (F)1.0; set_zero(&h1[1], L_SUBFR-1); syn_filt(Ap, h1, h1, L_SUBFR, &h1[1], 0); /*-----------------------------------------------* * Find the target vector for pitch search: * *----------------------------------------------*/ syn_filt(Ap, &exc[i_subfr], xn, L_SUBFR, mem_w0, 0); /*-----------------------------------------------------------------* * Closed-loop fractional pitch search * *-----------------------------------------------------------------*/ T0 = pitch_fr3_fast(&exc[i_subfr], xn, h1, L_SUBFR, T0_min, T0_max, i_subfr, &T0_frac); index = enc_lag3(T0, T0_frac, &T0_min, &T0_max, PIT_MIN, PIT_MAX, i_subfr); *ana++ = index; if (i_subfr == 0) *ana++ = parity_pitch(index); /*-----------------------------------------------------------------* * - find filtered pitch exc * * - compute pitch gain and limit between 0 and 1.2 * * - update target vector for codebook search * * - find LTP residual. * *-----------------------------------------------------------------*/ syn_filt(Ap, &exc[i_subfr], y1, L_SUBFR, mem_zero, 0); 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 (gain_pit > GPCLIP) { gain_pit = GPCLIP; } } for (i = 0; i < L_SUBFR; i++) xn2[i] = xn[i] - y1[i]*gain_pit; /*-----------------------------------------------------* * - Innovative codebook search. * *-----------------------------------------------------*/ index = ACELP_code_A(xn2, h1, T0, sharp, code, y2, &i); *ana++ = index; /* Positions index */ *ana++ = i; /* Signs index */ /*------------------------------------------------------* * - Compute the correlations <y2,y2>, <xn,y2>, <y1,y2>* * - Vector quantize gains. * *------------------------------------------------------*/ corr_xy2(xn, y1, y2, g_coeff); *ana++ =qua_gain(code, g_coeff, L_SUBFR, &gain_pit, &gain_code, taming); /*------------------------------------------------------------* * - Update pitch sharpening "sharp" with quantized gain_pit * *------------------------------------------------------------*/ sharp = gain_pit; if (sharp > SHARPMAX) sharp = SHARPMAX; if (sharp < SHARPMIN) sharp = SHARPMIN; /*------------------------------------------------------* * - Find the total excitation * * - update filters' memories for finding the target * * vector in the next subframe (mem_w0[]) * *------------------------------------------------------*/ for (i = 0; i < L_SUBFR; i++) exc[i+i_subfr] = gain_pit*exc[i+i_subfr] + gain_code*code[i]; update_exc_err(gain_pit, T0); for (i = L_SUBFR-M, j = 0; i < L_SUBFR; i++, j++) mem_w0[j] = xn[i] - gain_pit*y1[i] - gain_code*y2[i]; Aq += MP1; /* interpolated LPC parameters for next subframe */ Ap += MP1; } /*--------------------------------------------------* * 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); return; }