void StateConstructW(
int idxForMax, /* (i) 6-bit index for the quantization of
max amplitude */
int *idxVec, /* (i) vector of quantization indexes */
float *syntDenum, /* (i) synthesis filter denumerator */
float *out, /* (o) the decoded state vector */
int len /* (i) length of a state vector */
){
float maxVal, tmpbuf[LPC_FILTERORDER+2*STATE_LEN], *tmp,
numerator[LPC_FILTERORDER+1];
float foutbuf[LPC_FILTERORDER+2*STATE_LEN], *fout;
int k,tmpi;
/* decoding of the maximum value */
maxVal = state_frgqTbl[idxForMax];
maxVal = (float)pow(10,maxVal)/(float)4.5;
/* initialization of buffers and coefficients */
memset(tmpbuf, 0, LPC_FILTERORDER*sizeof(float));
memset(foutbuf, 0, LPC_FILTERORDER*sizeof(float));
for (k=0; k<LPC_FILTERORDER; k++) {
numerator[k]=syntDenum[LPC_FILTERORDER-k];
}
numerator[LPC_FILTERORDER]=syntDenum[0];
tmp = &tmpbuf[LPC_FILTERORDER];
fout = &foutbuf[LPC_FILTERORDER];
/* decoding of the sample values */
for (k=0; k<len; k++) {
tmpi = len-1-k;
/* maxVal = 1/scal */
tmp[k] = maxVal*state_sq3Tbl[idxVec[tmpi]];
}
/* circular convolution with all-pass filter */
memset(tmp+len, 0, len*sizeof(float));
ZeroPoleFilter(tmp, numerator, syntDenum, 2*len,
LPC_FILTERORDER, fout);
for (k=0;k<len;k++) {
out[k] = fout[len-1-k]+fout[2*len-1-k];
}
}
void StateSearchW(
iLBC_Enc_Inst_t *iLBCenc_inst,
/* (i) Encoder instance */
float *residual,/* (i) target residual vector */
float *syntDenum, /* (i) lpc synthesis filter */
float *weightDenum, /* (i) weighting filter denuminator */
int *idxForMax, /* (o) quantizer index for maximum
amplitude */
int *idxVec, /* (o) vector of quantization indexes */
int len, /* (i) length of all vectors */
int state_first /* (i) position of start state in the
80 vec */
){
float dtmp, maxVal;
float tmpbuf[LPC_FILTERORDER+2*STATE_SHORT_LEN_30MS];
float *tmp, numerator[1+LPC_FILTERORDER];
float foutbuf[LPC_FILTERORDER+2*STATE_SHORT_LEN_30MS], *fout;
int k;
float qmax, scal;
/* initialization of buffers and filter coefficients */
memset(tmpbuf, 0, LPC_FILTERORDER*sizeof(float));
memset(foutbuf, 0, LPC_FILTERORDER*sizeof(float));
for (k=0; k<LPC_FILTERORDER; k++) {
numerator[k]=syntDenum[LPC_FILTERORDER-k];
}
numerator[LPC_FILTERORDER]=syntDenum[0];
tmp = &tmpbuf[LPC_FILTERORDER];
fout = &foutbuf[LPC_FILTERORDER];
/* circular convolution with the all-pass filter */
memcpy(tmp, residual, len*sizeof(float));
memset(tmp+len, 0, len*sizeof(float));
ZeroPoleFilter(tmp, numerator, syntDenum, 2*len,
LPC_FILTERORDER, fout);
for (k=0; k<len; k++) {
fout[k] += fout[k+len];
}
/* identification of the maximum amplitude value */
maxVal = fout[0];
for (k=1; k<len; k++) {
if (fout[k]*fout[k] > maxVal*maxVal){
maxVal = fout[k];
}
}
maxVal=(float)fabs(maxVal);
/* encoding of the maximum amplitude value */
if (maxVal < 10.0) {
maxVal = 10.0;
}
maxVal = (float)log10(maxVal);
sort_sq(&dtmp, idxForMax, maxVal, state_frgqTbl, 64);
/* decoding of the maximum amplitude representation value,
and corresponding scaling of start state */
maxVal=state_frgqTbl[*idxForMax];
qmax = (float)pow(10,maxVal);
scal = (float)(4.5)/qmax;
for (k=0; k<len; k++){
fout[k] *= scal;
}
/* predictive noise shaping encoding of scaled start state */
AbsQuantW(iLBCenc_inst, fout,syntDenum,
weightDenum,idxVec, len, state_first);
}
