/*--------------------------------------------------------------------------
* 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 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);
}
