int enhancerInterface(
float *out, /* (o) enhanced signal */
float *in, /* (i) unenhanced signal */
iLBC_Dec_Inst_t *iLBCdec_inst /* (i) buffers etc */
){
float *enh_buf, *enh_period;
int iblock, isample;
int lag=0, ilag, i, ioffset;
float cc, maxcc;
float ftmp1, ftmp2;
float *inPtr, *enh_bufPtr1, *enh_bufPtr2;
float plc_pred[ENH_BLOCKL];
float lpState[6], downsampled[(ENH_NBLOCKS*ENH_BLOCKL+120)/2];
int inLen=ENH_NBLOCKS*ENH_BLOCKL+120;
int start, plc_blockl, inlag;
enh_buf=iLBCdec_inst->enh_buf;
enh_period=iLBCdec_inst->enh_period;
memmove(enh_buf, &enh_buf[iLBCdec_inst->blockl],
(ENH_BUFL-iLBCdec_inst->blockl)*sizeof(float));
memcpy(&enh_buf[ENH_BUFL-iLBCdec_inst->blockl], in,
iLBCdec_inst->blockl*sizeof(float));
if (iLBCdec_inst->mode==30)
plc_blockl=ENH_BLOCKL;
else
plc_blockl=40;
/* when 20 ms frame, move processing one block */
ioffset=0;
if (iLBCdec_inst->mode==20) ioffset=1;
i=3-ioffset;
memmove(enh_period, &enh_period[i],
(ENH_NBLOCKS_TOT-i)*sizeof(float));
/* Set state information to the 6 samples right before
the samples to be downsampled. */
memcpy(lpState,
enh_buf+(ENH_NBLOCKS_EXTRA+ioffset)*ENH_BLOCKL-126,
6*sizeof(float));
/* Down sample a factor 2 to save computations */
DownSample(enh_buf+(ENH_NBLOCKS_EXTRA+ioffset)*ENH_BLOCKL-120,
lpFilt_coefsTbl, inLen-ioffset*ENH_BLOCKL,
lpState, downsampled);
/* Estimate the pitch in the down sampled domain. */
for (iblock = 0; iblock<ENH_NBLOCKS-ioffset; iblock++) {
lag = 10;
maxcc = xCorrCoef(downsampled+60+iblock*
ENH_BLOCKL_HALF, downsampled+60+iblock*
ENH_BLOCKL_HALF-lag, ENH_BLOCKL_HALF);
for (ilag=11; ilag<60; ilag++) {
cc = xCorrCoef(downsampled+60+iblock*
ENH_BLOCKL_HALF, downsampled+60+iblock*
ENH_BLOCKL_HALF-ilag, ENH_BLOCKL_HALF);
if (cc > maxcc) {
maxcc = cc;
lag = ilag;
}
}
/* Store the estimated lag in the non-downsampled domain */
enh_period[iblock+ENH_NBLOCKS_EXTRA+ioffset] = (float)lag*2;
}
/* PLC was performed on the previous packet */
if (iLBCdec_inst->prev_enh_pl==1) {
inlag=(int)enh_period[ENH_NBLOCKS_EXTRA+ioffset];
lag = inlag-1;
maxcc = xCorrCoef(in, in+lag, plc_blockl);
for (ilag=inlag; ilag<=inlag+1; ilag++) {
cc = xCorrCoef(in, in+ilag, plc_blockl);
if (cc > maxcc) {
maxcc = cc;
lag = ilag;
}
}
enh_period[ENH_NBLOCKS_EXTRA+ioffset-1]=(float)lag;
/* compute new concealed residual for the old lookahead,
mix the forward PLC with a backward PLC from
the new frame */
inPtr=&in[lag-1];
enh_bufPtr1=&plc_pred[plc_blockl-1];
if (lag>plc_blockl) {
start=plc_blockl;
} else {
start=lag;
}
for (isample = start; isample>0; isample--) {
*enh_bufPtr1-- = *inPtr--;
}
enh_bufPtr2=&enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl];
for (isample = (plc_blockl-1-lag); isample>=0; isample--) {
*enh_bufPtr1-- = *enh_bufPtr2--;
}
/* limit energy change */
ftmp2=0.0;
ftmp1=0.0;
for (i=0;i<plc_blockl;i++) {
ftmp2+=enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl-i]*
enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl-i];
ftmp1+=plc_pred[i]*plc_pred[i];
}
ftmp1=(float)sqrt(ftmp1/(float)plc_blockl);
ftmp2=(float)sqrt(ftmp2/(float)plc_blockl);
if (ftmp1>(float)2.0*ftmp2 && ftmp1>0.0) {
for (i=0;i<plc_blockl-10;i++) {
plc_pred[i]*=(float)2.0*ftmp2/ftmp1;
}
for (i=plc_blockl-10;i<plc_blockl;i++) {
plc_pred[i]*=(float)(i-plc_blockl+10)*
((float)1.0-(float)2.0*ftmp2/ftmp1)/(float)(10)+
(float)2.0*ftmp2/ftmp1;
}
}
enh_bufPtr1=&enh_buf[ENH_BUFL-1-iLBCdec_inst->blockl];
for (i=0; i<plc_blockl; i++) {
ftmp1 = (float) (i+1) / (float) (plc_blockl+1);
*enh_bufPtr1 *= ftmp1;
*enh_bufPtr1 += ((float)1.0-ftmp1)*
plc_pred[plc_blockl-1-i];
enh_bufPtr1--;
}
}
if (iLBCdec_inst->mode==20) {
/* Enhancer with 40 samples delay */
for (iblock = 0; iblock<2; iblock++) {
enhancer(out+iblock*ENH_BLOCKL, enh_buf,
ENH_BUFL, (5+iblock)*ENH_BLOCKL+40,
ENH_ALPHA0, enh_period, enh_plocsTbl,
ENH_NBLOCKS_TOT);
}
} else if (iLBCdec_inst->mode==30) {
/* Enhancer with 80 samples delay */
for (iblock = 0; iblock<3; iblock++) {
enhancer(out+iblock*ENH_BLOCKL, enh_buf,
ENH_BUFL, (4+iblock)*ENH_BLOCKL,
ENH_ALPHA0, enh_period, enh_plocsTbl,
ENH_NBLOCKS_TOT);
}
}
return (lag*2);
}
void iLBC_decode(
float *decblock, /* (o) decoded signal block */
unsigned char *bytes, /* (i) encoded signal bits */
iLBC_Dec_Inst_t *iLBCdec_inst, /* (i/o) the decoder state
structure */
int mode /* (i) 0: bad packet, PLC,
1: normal */
){
float data[BLOCKL_MAX];
float lsfdeq[LPC_FILTERORDER*LPC_N_MAX];
float PLCresidual[BLOCKL_MAX], PLClpc[LPC_FILTERORDER + 1];
float zeros[BLOCKL_MAX], one[LPC_FILTERORDER + 1];
int k, i, start, idxForMax, pos, lastpart, ulp;
int lag, ilag;
float cc, maxcc;
int idxVec[STATE_LEN];
int gain_index[NASUB_MAX*CB_NSTAGES],
extra_gain_index[CB_NSTAGES];
int cb_index[CB_NSTAGES*NASUB_MAX], extra_cb_index[CB_NSTAGES];
int lsf_i[LSF_NSPLIT*LPC_N_MAX];
int state_first;
int last_bit;
unsigned char *pbytes;
float weightdenum[(LPC_FILTERORDER + 1)*NSUB_MAX];
int order_plus_one;
float syntdenum[NSUB_MAX*(LPC_FILTERORDER+1)];
float decresidual[BLOCKL_MAX];
if (mode>0) { /* the data are good */
/* decode data */
pbytes=bytes;
pos=0;
/* Set everything to zero before decoding */
for (k=0; k<LSF_NSPLIT*LPC_N_MAX; k++) {
lsf_i[k]=0;
}
start=0;
state_first=0;
idxForMax=0;
for (k=0; k<iLBCdec_inst->state_short_len; k++) {
idxVec[k]=0;
}
for (k=0; k<CB_NSTAGES; k++) {
extra_cb_index[k]=0;
}
for (k=0; k<CB_NSTAGES; k++) {
extra_gain_index[k]=0;
}
for (i=0; i<iLBCdec_inst->nasub; i++) {
for (k=0; k<CB_NSTAGES; k++) {
cb_index[i*CB_NSTAGES+k]=0;
}
}
for (i=0; i<iLBCdec_inst->nasub; i++) {
for (k=0; k<CB_NSTAGES; k++) {
gain_index[i*CB_NSTAGES+k]=0;
}
}
/* loop over ULP classes */
for (ulp=0; ulp<3; ulp++) {
/* LSF */
for (k=0; k<LSF_NSPLIT*iLBCdec_inst->lpc_n; k++){
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->lsf_bits[k][ulp], &pos);
packcombine(&lsf_i[k], lastpart,
iLBCdec_inst->ULP_inst->lsf_bits[k][ulp]);
}
/* Start block info */
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->start_bits[ulp], &pos);
packcombine(&start, lastpart,
iLBCdec_inst->ULP_inst->start_bits[ulp]);
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->startfirst_bits[ulp], &pos);
packcombine(&state_first, lastpart,
iLBCdec_inst->ULP_inst->startfirst_bits[ulp]);
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->scale_bits[ulp], &pos);
packcombine(&idxForMax, lastpart,
iLBCdec_inst->ULP_inst->scale_bits[ulp]);
for (k=0; k<iLBCdec_inst->state_short_len; k++) {
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->state_bits[ulp], &pos);
packcombine(idxVec+k, lastpart,
iLBCdec_inst->ULP_inst->state_bits[ulp]);
}
/* 23/22 (20ms/30ms) sample block */
for (k=0; k<CB_NSTAGES; k++) {
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->extra_cb_index[k][ulp],
&pos);
packcombine(extra_cb_index+k, lastpart,
iLBCdec_inst->ULP_inst->extra_cb_index[k][ulp]);
}
for (k=0; k<CB_NSTAGES; k++) {
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->extra_cb_gain[k][ulp],
&pos);
packcombine(extra_gain_index+k, lastpart,
iLBCdec_inst->ULP_inst->extra_cb_gain[k][ulp]);
}
/* The two/four (20ms/30ms) 40 sample sub-blocks */
for (i=0; i<iLBCdec_inst->nasub; i++) {
for (k=0; k<CB_NSTAGES; k++) {
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->cb_index[i][k][ulp],
&pos);
packcombine(cb_index+i*CB_NSTAGES+k, lastpart,
iLBCdec_inst->ULP_inst->cb_index[i][k][ulp]);
}
}
for (i=0; i<iLBCdec_inst->nasub; i++) {
for (k=0; k<CB_NSTAGES; k++) {
unpack( &pbytes, &lastpart,
iLBCdec_inst->ULP_inst->cb_gain[i][k][ulp],
&pos);
packcombine(gain_index+i*CB_NSTAGES+k, lastpart,
iLBCdec_inst->ULP_inst->cb_gain[i][k][ulp]);
}
}
}
/* Extract last bit. If it is 1 this indicates an
empty/lost frame */
unpack( &pbytes, &last_bit, 1, &pos);
/* Check for bit errors or empty/lost frames */
if (start<1)
mode = 0;
if (iLBCdec_inst->mode==20 && start>3)
mode = 0;
if (iLBCdec_inst->mode==30 && start>5)
mode = 0;
if (last_bit==1)
mode = 0;
if (mode==1) { /* No bit errors was detected,
continue decoding */
/* adjust index */
index_conv_dec(cb_index);
/* decode the lsf */
SimplelsfDEQ(lsfdeq, lsf_i, iLBCdec_inst->lpc_n);
LSF_check(lsfdeq, LPC_FILTERORDER,
iLBCdec_inst->lpc_n);
DecoderInterpolateLSF(syntdenum, weightdenum,
lsfdeq, LPC_FILTERORDER, iLBCdec_inst);
Decode(iLBCdec_inst, decresidual, start, idxForMax,
idxVec, syntdenum, cb_index, gain_index,
extra_cb_index, extra_gain_index,
state_first);
/* preparing the plc for a future loss! */
doThePLC(PLCresidual, PLClpc, 0, decresidual,
syntdenum +
(LPC_FILTERORDER + 1)*(iLBCdec_inst->nsub - 1),
(*iLBCdec_inst).last_lag, iLBCdec_inst);
memcpy(decresidual, PLCresidual,
iLBCdec_inst->blockl*sizeof(float));
}
}
if (mode == 0) {
/* the data is bad (either a PLC call
* was made or a severe bit error was detected)
*/
/* packet loss conceal */
memset(zeros, 0, BLOCKL_MAX*sizeof(float));
one[0] = 1;
memset(one+1, 0, LPC_FILTERORDER*sizeof(float));
start=0;
doThePLC(PLCresidual, PLClpc, 1, zeros, one,
(*iLBCdec_inst).last_lag, iLBCdec_inst);
memcpy(decresidual, PLCresidual,
iLBCdec_inst->blockl*sizeof(float));
order_plus_one = LPC_FILTERORDER + 1;
for (i = 0; i < iLBCdec_inst->nsub; i++) {
memcpy(syntdenum+(i*order_plus_one), PLClpc,
order_plus_one*sizeof(float));
}
}
if (iLBCdec_inst->use_enhancer == 1) {
/* post filtering */
iLBCdec_inst->last_lag =
enhancerInterface(data, decresidual, iLBCdec_inst);
/* synthesis filtering */
if (iLBCdec_inst->mode==20) {
/* Enhancer has 40 samples delay */
i=0;
syntFilter(data + i*SUBL,
iLBCdec_inst->old_syntdenum +
(i+iLBCdec_inst->nsub-1)*(LPC_FILTERORDER+1),
SUBL, iLBCdec_inst->syntMem);
for (i=1; i < iLBCdec_inst->nsub; i++) {
syntFilter(data + i*SUBL,
syntdenum + (i-1)*(LPC_FILTERORDER+1),
SUBL, iLBCdec_inst->syntMem);
}
} else if (iLBCdec_inst->mode==30) {
/* Enhancer has 80 samples delay */
for (i=0; i < 2; i++) {
syntFilter(data + i*SUBL,
iLBCdec_inst->old_syntdenum +
(i+iLBCdec_inst->nsub-2)*(LPC_FILTERORDER+1),
SUBL, iLBCdec_inst->syntMem);
}
for (i=2; i < iLBCdec_inst->nsub; i++) {
syntFilter(data + i*SUBL,
syntdenum + (i-2)*(LPC_FILTERORDER+1), SUBL,
iLBCdec_inst->syntMem);
}
}
} else {
/* Find last lag */
lag = 20;
maxcc = xCorrCoef(&decresidual[BLOCKL_MAX-ENH_BLOCKL],
&decresidual[BLOCKL_MAX-ENH_BLOCKL-lag], ENH_BLOCKL);
for (ilag=21; ilag<120; ilag++) {
cc = xCorrCoef(&decresidual[BLOCKL_MAX-ENH_BLOCKL],
&decresidual[BLOCKL_MAX-ENH_BLOCKL-ilag],
ENH_BLOCKL);
if (cc > maxcc) {
maxcc = cc;
lag = ilag;
}
}
iLBCdec_inst->last_lag = lag;
/* copy data and run synthesis filter */
memcpy(data, decresidual,
iLBCdec_inst->blockl*sizeof(float));
for (i=0; i < iLBCdec_inst->nsub; i++) {
syntFilter(data + i*SUBL,
syntdenum + i*(LPC_FILTERORDER+1), SUBL,
iLBCdec_inst->syntMem);
}
}
/* high pass filtering on output if desired, otherwise
copy to out */
hpOutput(data, iLBCdec_inst->blockl,
decblock,iLBCdec_inst->hpomem);
/* memcpy(decblock,data,iLBCdec_inst->blockl*sizeof(float));*/
memcpy(iLBCdec_inst->old_syntdenum, syntdenum,
iLBCdec_inst->nsub*(LPC_FILTERORDER+1)*sizeof(float));
iLBCdec_inst->prev_enh_pl=0;
if (mode==0) { /* PLC was used */
iLBCdec_inst->prev_enh_pl=1;
}
}